Rewrite images to use local proxy (#4035)

* Add markdown rule to add rel=nofollow for all links

* Add markdown image rule to add local image proxy (fixes #1036)

* comments

* rewrite markdown image links working

* add comment

* perform markdown image processing in api/apub receivers

* clippy

* add db table to validate proxied links

* rewrite link fields for avatar, banner etc

* sql fmt

* proxy links received over federation

* add config option

* undo post.url rewriting, move http route definition

* add tests

* proxy images through pictrs

* testing

* cleanup request.rs file

* more cleanup (fixes #2611)

* include url content type when sending post over apub (fixes #2611)

* store post url content type in db

* should be media_type

* get rid of cache_remote_thumbnails setting, instead automatically
take thumbnail from federation data if available.

* fix tests

* add setting disable_external_link_previews

* federate post url as image depending on mime type

* change setting again

* machete

* invert

* support custom emoji

* clippy

* update defaults

* add image proxy test, fix test

* fix test

* clippy

* revert accidental changes

* address review

* clippy

* Markdown link rule-dess (#4356)

* Extracting opengraph_data to its own type.

* A few additions for markdown-link-rule.

---------

Co-authored-by: Nutomic <me@nutomic.com>

* fix setting

* use enum for image proxy setting

* fix test configs

* add config backwards compat

* clippy

* machete

---------

Co-authored-by: Dessalines <dessalines@users.noreply.github.com>

Cargo.lock

@@ -2571,6 +2571,8 @@ version = "0.19.3"
 dependencies = [
  "activitypub_federation",
  "actix-web",
+ "anyhow",
+ "async-trait",
  "chrono",
  "encoding",
  "enum-map",
@@ -2582,8 +2584,8 @@ dependencies = [
  "lemmy_db_views_actor",
  "lemmy_db_views_moderator",
  "lemmy_utils",
+ "mime",
  "once_cell",
- "percent-encoding",
  "pretty_assertions",
  "regex",
  "reqwest",
@@ -2592,10 +2594,12 @@ dependencies = [
  "serde",
  "serde_with",
  "serial_test",
+ "task-local-extensions",
  "tokio",
  "tracing",
  "ts-rs",
  "url",
+ "urlencoding",
  "uuid",
  "webpage",
 ]
@@ -2648,14 +2652,12 @@ dependencies = [
  "once_cell",
  "pretty_assertions",
  "reqwest",
- "reqwest-middleware",
  "serde",
  "serde_json",
  "serde_with",
  "serial_test",
  "stringreader",
  "strum_macros",
- "task-local-extensions",
  "tokio",
  "tracing",
  "url",
@@ -2811,6 +2813,7 @@ dependencies = [
  "tokio",
  "tracing",
  "url",
+ "urlencoding",
 ]
 
 [[package]]
@@ -2874,7 +2877,6 @@ dependencies = [
  "markdown-it",
  "once_cell",
  "openssl",
- "percent-encoding",
  "pretty_assertions",
  "regex",
  "reqwest",
@@ -2891,6 +2893,7 @@ dependencies = [
  "tracing-error",
  "ts-rs",
  "url",
+ "urlencoding",
  "uuid",
 ]
 

Cargo.toml

@@ -146,7 +146,6 @@ strum_macros = "0.25.3"
 itertools = "0.12.0"
 futures = "0.3.30"
 http = "0.2.11"
-percent-encoding = "2.3.1"
 rosetta-i18n = "0.1.3"
 opentelemetry = { version = "0.19.0", features = ["rt-tokio"] }
 tracing-opentelemetry = { version = "0.19.0" }
@@ -155,6 +154,7 @@ rustls = { version = "0.21.10", features = ["dangerous_configuration"] }
 futures-util = "0.3.30"
 tokio-postgres = "0.7.10"
 tokio-postgres-rustls = "0.10.0"
+urlencoding = "2.1.3"
 enum-map = "2.7"
 moka = { version = "0.12.4", features = ["future"] }
 i-love-jesus = { version = "0.1.0" }

api_tests/src/image.spec.ts

@@ -7,16 +7,23 @@ import {
   PurgePost,
 } from "lemmy-js-client";
 import {
+  alpha,
   alphaImage,
   alphaUrl,
   beta,
   betaUrl,
+  createCommunity,
   createPost,
+  delta,
+  epsilon,
+  gamma,
   getSite,
   registerUser,
   resolveBetaCommunity,
+  resolvePost,
   setupLogins,
   unfollowRemotes,
+  waitForPost,
 } from "./shared";
 const downloadFileSync = require("download-file-sync");
 
@@ -29,9 +36,8 @@ afterAll(() => {
 test("Upload image and delete it", async () => {
   // Upload test image. We use a simple string buffer as pictrs doesnt require an actual image
   // in testing mode.
-  const upload_image = Buffer.from("test");
   const upload_form: UploadImage = {
-    image: upload_image,
+    image: Buffer.from("test"),
   };
   const upload = await alphaImage.uploadImage(upload_form);
   expect(upload.files![0].file).toBeDefined();
@@ -60,9 +66,8 @@ test("Purge user, uploaded image removed", async () => {
   let user = await registerUser(alphaImage, alphaUrl);
 
   // upload test image
-  const upload_image = Buffer.from("test");
   const upload_form: UploadImage = {
-    image: upload_image,
+    image: Buffer.from("test"),
   };
   const upload = await user.uploadImage(upload_form);
   expect(upload.files![0].file).toBeDefined();
@@ -91,9 +96,8 @@ test("Purge post, linked image removed", async () => {
   let user = await registerUser(beta, betaUrl);
 
   // upload test image
-  const upload_image = Buffer.from("test");
   const upload_form: UploadImage = {
-    image: upload_image,
+    image: Buffer.from("test"),
   };
   const upload = await user.uploadImage(upload_form);
   expect(upload.files![0].file).toBeDefined();
@@ -124,3 +128,79 @@ test("Purge post, linked image removed", async () => {
   const content2 = downloadFileSync(upload.url);
   expect(content2).toBe("");
 });
+
+test("Images in remote post are proxied if setting enabled", async () => {
+  let user = await registerUser(beta, betaUrl);
+  let community = await createCommunity(gamma);
+
+  const upload_form: UploadImage = {
+    image: Buffer.from("test"),
+  };
+  const upload = await user.uploadImage(upload_form);
+  let post = await createPost(
+    gamma,
+    community.community_view.community.id,
+    upload.url,
+    "![](http://example.com/image2.png)",
+  );
+  expect(post.post_view.post).toBeDefined();
+
+  // remote image gets proxied after upload
+  expect(
+    post.post_view.post.url?.startsWith(
+      "http://lemmy-gamma:8561/api/v3/image_proxy?url",
+    ),
+  ).toBeTruthy();
+  expect(
+    post.post_view.post.body?.startsWith(
+      "![](http://lemmy-gamma:8561/api/v3/image_proxy?url",
+    ),
+  ).toBeTruthy();
+
+  let epsilonPost = await resolvePost(epsilon, post.post_view.post);
+  expect(epsilonPost.post).toBeDefined();
+
+  // remote image gets proxied after federation
+  expect(
+    epsilonPost.post!.post.url?.startsWith(
+      "http://lemmy-epsilon:8581/api/v3/image_proxy?url",
+    ),
+  ).toBeTruthy();
+  expect(
+    epsilonPost.post!.post.body?.startsWith(
+      "![](http://lemmy-epsilon:8581/api/v3/image_proxy?url",
+    ),
+  ).toBeTruthy();
+});
+
+test("No image proxying if setting is disabled", async () => {
+  let user = await registerUser(beta, betaUrl);
+  let community = await createCommunity(alpha);
+
+  const upload_form: UploadImage = {
+    image: Buffer.from("test"),
+  };
+  const upload = await user.uploadImage(upload_form);
+  let post = await createPost(
+    alpha,
+    community.community_view.community.id,
+    upload.url,
+    "![](http://example.com/image2.png)",
+  );
+  expect(post.post_view.post).toBeDefined();
+
+  // remote image doesnt get proxied after upload
+  expect(
+    post.post_view.post.url?.startsWith("http://127.0.0.1:8551/pictrs/image/"),
+  ).toBeTruthy();
+  expect(post.post_view.post.body).toBe("![](http://example.com/image2.png)");
+
+  let gammaPost = await resolvePost(delta, post.post_view.post);
+  expect(gammaPost.post).toBeDefined();
+
+  // remote image doesnt get proxied after federation
+  expect(
+    gammaPost.post!.post.url?.startsWith("http://127.0.0.1:8551/pictrs/image/"),
+  ).toBeTruthy();
+  expect(gammaPost.post!.post.body).toBe("![](http://example.com/image2.png)");
+});

api_tests/src/post.spec.ts

@@ -39,7 +39,7 @@ import {
   loginUser,
 } from "./shared";
 import { PostView } from "lemmy-js-client/dist/types/PostView";
-import { ResolveObject } from "lemmy-js-client";
+import { EditSite, ResolveObject } from "lemmy-js-client";
 
 let betaCommunity: CommunityView | undefined;
 
@@ -72,6 +72,16 @@ function assertPostFederation(postOne?: PostView, postTwo?: PostView) {
 }
 
 test("Create a post", async () => {
+  // Setup some allowlists and blocklists
+  let editSiteForm: EditSite = {
+    allowed_instances: ["lemmy-beta"],
+  };
+  await delta.editSite(editSiteForm);
+
+  editSiteForm.allowed_instances = [];
+  editSiteForm.blocked_instances = ["lemmy-alpha"];
+  await epsilon.editSite(editSiteForm);
+
   if (!betaCommunity) {
     throw "Missing beta community";
   }
@@ -109,6 +119,12 @@ test("Create a post", async () => {
   await expect(
     resolvePost(epsilon, postRes.post_view.post),
   ).rejects.toStrictEqual(Error("couldnt_find_object"));
+
+  // remove added allow/blocklists
+  editSiteForm.allowed_instances = [];
+  editSiteForm.blocked_instances = [];
+  await delta.editSite(editSiteForm);
+  await epsilon.editSite(editSiteForm);
 });
 
 test("Create a post in a non-existent community", async () => {

api_tests/src/shared.ts

@@ -177,13 +177,6 @@ export async function setupLogins() {
   ];
   await gamma.editSite(editSiteForm);
 
-  editSiteForm.allowed_instances = ["lemmy-beta"];
-  await delta.editSite(editSiteForm);
-
-  editSiteForm.allowed_instances = [];
-  editSiteForm.blocked_instances = ["lemmy-alpha"];
-  await epsilon.editSite(editSiteForm);
-
   // Create the main alpha/beta communities
   // Ignore thrown errors of duplicates
   try {
@@ -203,10 +196,10 @@ export async function createPost(
   api: LemmyHttp,
   community_id: number,
   url: string = "https://example.com/",
+  body = randomString(10),
   // use example.com for consistent title and embed description
   name: string = randomString(5),
 ): Promise<PostResponse> {
-  let body = randomString(10);
   let form: CreatePost = {
     name,
     url,
@@ -528,7 +521,7 @@ export async function likeComment(
 
 export async function createCommunity(
   api: LemmyHttp,
-  name_: string = randomString(5),
+  name_: string = randomString(10),
 ): Promise<CommunityResponse> {
   let description = "a sample description";
   let form: CreateCommunity = {

config/defaults.hjson

@@ -36,22 +36,41 @@
     # Maximum number of active sql connections
     pool_size: 30
   }
-  # Settings related to activitypub federation
   # Pictrs image server configuration.
   pictrs: {
     # Address where pictrs is available (for image hosting)
     url: "http://localhost:8080/"
     # Set a custom pictrs API key. ( Required for deleting images )
     api_key: "string"
-    # By default the thumbnails for external links are stored in pict-rs. This ensures that they
+    # Backwards compatibility with 0.18.1. False is equivalent to `image_mode: None`, true is
-    # can be reliably retrieved and can be resized using pict-rs APIs. However it also increases
+    # equivalent to `image_mode: StoreLinkPreviews`.
-    # storage usage. In case this is disabled, the Opengraph image is directly returned as
-    # thumbnail.
     # 
-    # In some countries it is forbidden to copy preview images from newspaper articles and only
+    # To be removed in 0.20
-    # hotlinking is allowed. If that is the case for your instance, make sure that this setting is
-    # disabled.
     cache_external_link_previews: true
+    # Specifies how to handle remote images, so that users don't have to connect directly to remote servers.
+    image_mode: 
+      # Leave images unchanged, don't generate any local thumbnails for post urls. Instead the the
+      # Opengraph image is directly returned as thumbnail
+      "None"
+
+      # or
+
+      # Generate thumbnails for external post urls and store them persistently in pict-rs. This
+      # ensures that they can be reliably retrieved and can be resized using pict-rs APIs. However
+      # it also increases storage usage.
+      # 
+      # This is the default behaviour, and also matches Lemmy 0.18.
+      "StoreLinkPreviews"
+
+      # or
+
+      # If enabled, all images from remote domains are rewritten to pass through `/api/v3/image_proxy`,
+      # including embedded images in markdown. Images are stored temporarily in pict-rs for caching.
+      # This improves privacy as users don't expose their IP to untrusted servers, and decreases load
+      # on other servers. However it increases bandwidth use for the local server.
+      # 
+      # Requires pict-rs 0.5
+      "ProxyAllImages"
     # Timeout for uploading images to pictrs (in seconds)
     upload_timeout: 30
   }

crates/api/src/local_user/save_settings.rs

@@ -2,7 +2,12 @@ use actix_web::web::{Data, Json};
 use lemmy_api_common::{
   context::LemmyContext,
   person::SaveUserSettings,
-  utils::send_verification_email,
+  utils::{
+    local_site_to_slur_regex,
+    process_markdown_opt,
+    proxy_image_link_opt_api,
+    send_verification_email,
+  },
   SuccessResponse,
 };
 use lemmy_db_schema::{
@@ -12,7 +17,7 @@ use lemmy_db_schema::{
     person::{Person, PersonUpdateForm},
   },
   traits::Crud,
-  utils::{diesel_option_overwrite, diesel_option_overwrite_to_url},
+  utils::diesel_option_overwrite,
 };
 use lemmy_db_views::structs::{LocalUserView, SiteView};
 use lemmy_utils::{
@@ -28,9 +33,11 @@ pub async fn save_user_settings(
 ) -> Result<Json<SuccessResponse>, LemmyError> {
   let site_view = SiteView::read_local(&mut context.pool()).await?;
 
-  let avatar = diesel_option_overwrite_to_url(&data.avatar)?;
+  let slur_regex = local_site_to_slur_regex(&site_view.local_site);
-  let banner = diesel_option_overwrite_to_url(&data.banner)?;
+  let bio = diesel_option_overwrite(process_markdown_opt(&data.bio, &slur_regex, &context).await?);
-  let bio = diesel_option_overwrite(data.bio.clone());
+
+  let avatar = proxy_image_link_opt_api(&data.avatar, &context).await?;
+  let banner = proxy_image_link_opt_api(&data.banner, &context).await?;
   let display_name = diesel_option_overwrite(data.display_name.clone());
   let matrix_user_id = diesel_option_overwrite(data.matrix_user_id.clone());
   let email_deref = data.email.as_deref().map(str::to_lowercase);

crates/api/src/post/get_link_metadata.rs

@@ -2,7 +2,7 @@ use actix_web::web::{Data, Json, Query};
 use lemmy_api_common::{
   context::LemmyContext,
   post::{GetSiteMetadata, GetSiteMetadataResponse},
-  request::fetch_site_metadata,
+  request::fetch_link_metadata,
 };
 use lemmy_utils::error::LemmyError;
 
@@ -11,7 +11,7 @@ pub async fn get_link_metadata(
   data: Query<GetSiteMetadata>,
   context: Data<LemmyContext>,
 ) -> Result<Json<GetSiteMetadataResponse>, LemmyError> {
-  let metadata = fetch_site_metadata(context.client(), &data.url).await?;
+  let metadata = fetch_link_metadata(&data.url, false, &context).await?;
 
   Ok(Json(GetSiteMetadataResponse { metadata }))
 }

crates/api/src/site/purge/person.rs

@@ -8,7 +8,7 @@ use lemmy_api_common::{
 };
 use lemmy_db_schema::{
   source::{
-    image_upload::ImageUpload,
+    images::LocalImage,
     moderator::{AdminPurgePerson, AdminPurgePersonForm},
     person::{Person, PersonUpdateForm},
   },
@@ -31,7 +31,7 @@ pub async fn purge_person(
 
   if let Ok(local_user) = LocalUserView::read_person(&mut context.pool(), person_id).await {
     let pictrs_uploads =
-      ImageUpload::get_all_by_local_user_id(&mut context.pool(), &local_user.local_user.id).await?;
+      LocalImage::get_all_by_local_user_id(&mut context.pool(), &local_user.local_user.id).await?;
 
     for upload in pictrs_uploads {
       delete_image_from_pictrs(&upload.pictrs_alias, &upload.pictrs_delete_token, &context)

crates/api_common/Cargo.toml

@@ -25,7 +25,6 @@ full = [
   "lemmy_db_views_actor/full",
   "lemmy_db_views_moderator/full",
   "activitypub_federation",
-  "percent-encoding",
   "encoding",
   "reqwest-middleware",
   "webpage",
@@ -37,6 +36,7 @@ full = [
   "futures",
   "once_cell",
   "jsonwebtoken",
+  "mime",
 ]
 
 [dependencies]
@@ -54,11 +54,7 @@ tracing = { workspace = true, optional = true }
 reqwest-middleware = { workspace = true, optional = true }
 regex = { workspace = true }
 rosetta-i18n = { workspace = true, optional = true }
-percent-encoding = { workspace = true, optional = true }
+anyhow = { workspace = true }
-webpage = { version = "1.6", default-features = false, features = [
-  "serde",
-], optional = true }
-encoding = { version = "0.2.33", optional = true }
 futures = { workspace = true, optional = true }
 uuid = { workspace = true, optional = true }
 tokio = { workspace = true, optional = true }
@@ -66,10 +62,18 @@ reqwest = { workspace = true, optional = true }
 ts-rs = { workspace = true, optional = true }
 once_cell = { workspace = true, optional = true }
 actix-web = { workspace = true, optional = true }
+enum-map = { workspace = true }
+urlencoding = { workspace = true }
+async-trait = { workspace = true }
+mime = { version = "0.3.17", optional = true }
+webpage = { version = "1.6", default-features = false, features = [
+  "serde",
+], optional = true }
+encoding = { version = "0.2.33", optional = true }
 jsonwebtoken = { version = "8.3.0", optional = true }
 # necessary for wasmt compilation
 getrandom = { version = "0.2.12", features = ["js"] }
-enum-map = { workspace = true }
+task-local-extensions = "0.1.4"
 
 [package.metadata.cargo-machete]
 ignored = ["getrandom"]

crates/api_common/src/context.rs

@@ -1,13 +1,18 @@
+use crate::request::client_builder;
+use activitypub_federation::config::{Data, FederationConfig};
+use anyhow::anyhow;
 use lemmy_db_schema::{
   source::secret::Secret,
-  utils::{ActualDbPool, DbPool},
+  utils::{build_db_pool_for_tests, ActualDbPool, DbPool},
 };
 use lemmy_utils::{
   rate_limit::RateLimitCell,
   settings::{structs::Settings, SETTINGS},
 };
-use reqwest_middleware::ClientWithMiddleware;
+use reqwest::{Request, Response};
+use reqwest_middleware::{ClientBuilder, ClientWithMiddleware, Middleware, Next};
 use std::sync::Arc;
+use task_local_extensions::Extensions;
 
 #[derive(Clone)]
 pub struct LemmyContext {
@@ -49,4 +54,62 @@ impl LemmyContext {
   pub fn rate_limit_cell(&self) -> &RateLimitCell {
     &self.rate_limit_cell
   }
+
+  /// Initialize a context for use in tests, optionally blocks network requests.
+  ///
+  /// Do not use this in production code.
+  pub async fn init_test_context() -> Data<LemmyContext> {
+    Self::build_test_context(true).await
+  }
+
+  /// Initialize a context for use in tests, with network requests allowed.
+  /// TODO: get rid of this if possible.
+  ///
+  /// Do not use this in production code.
+  pub async fn init_test_context_with_networking() -> Data<LemmyContext> {
+    Self::build_test_context(false).await
+  }
+
+  async fn build_test_context(block_networking: bool) -> Data<LemmyContext> {
+    // call this to run migrations
+    let pool = build_db_pool_for_tests().await;
+
+    let client = client_builder(&SETTINGS).build().expect("build client");
+
+    let mut client = ClientBuilder::new(client);
+    if block_networking {
+      client = client.with(BlockedMiddleware);
+    }
+    let client = client.build();
+    let secret = Secret {
+      id: 0,
+      jwt_secret: String::new(),
+    };
+
+    let rate_limit_cell = RateLimitCell::with_test_config();
+
+    let context = LemmyContext::create(pool, client, secret, rate_limit_cell.clone());
+    let config = FederationConfig::builder()
+      .domain(context.settings().hostname.clone())
+      .app_data(context)
+      .build()
+      .await
+      .expect("build federation config");
+    config.to_request_data()
+  }
+}
+
+struct BlockedMiddleware;
+
+/// A reqwest middleware which blocks all requests
+#[async_trait::async_trait]
+impl Middleware for BlockedMiddleware {
+  async fn handle(
+    &self,
+    _req: Request,
+    _extensions: &mut Extensions,
+    _next: Next<'_>,
+  ) -> reqwest_middleware::Result<Response> {
+    Err(anyhow!("Network requests not allowed").into())
+  }
 }

crates/api_common/src/post.rs

@@ -238,15 +238,28 @@ pub struct GetSiteMetadata {
 #[cfg_attr(feature = "full", ts(export))]
 /// The site metadata response.
 pub struct GetSiteMetadataResponse {
-  pub metadata: SiteMetadata,
+  pub metadata: LinkMetadata,
 }
 
 #[skip_serializing_none]
-#[derive(Debug, Deserialize, Serialize, PartialEq, Eq, Clone)]
+#[derive(Debug, Deserialize, Serialize, PartialEq, Eq, Clone, Default)]
 #[cfg_attr(feature = "full", derive(TS))]
 #[cfg_attr(feature = "full", ts(export))]
 /// Site metadata, from its opengraph tags.
-pub struct SiteMetadata {
+pub struct LinkMetadata {
+  #[serde(flatten)]
+  pub opengraph_data: OpenGraphData,
+  pub content_type: Option<String>,
+  #[serde(skip)]
+  pub thumbnail: Option<DbUrl>,
+}
+
+#[skip_serializing_none]
+#[derive(Debug, Deserialize, Serialize, PartialEq, Eq, Clone, Default)]
+#[cfg_attr(feature = "full", derive(TS))]
+#[cfg_attr(feature = "full", ts(export))]
+/// Site metadata, from its opengraph tags.
+pub struct OpenGraphData {
   pub title: Option<String>,
   pub description: Option<String>,
   pub(crate) image: Option<DbUrl>,

crates/api_common/src/request.rs

@@ -1,39 +1,91 @@
-use crate::{context::LemmyContext, post::SiteMetadata};
+use crate::{
+  context::LemmyContext,
+  post::{LinkMetadata, OpenGraphData},
+  utils::proxy_image_link,
+};
 use encoding::{all::encodings, DecoderTrap};
 use lemmy_db_schema::newtypes::DbUrl;
 use lemmy_utils::{
   error::{LemmyError, LemmyErrorType},
-  settings::structs::Settings,
+  settings::structs::{PictrsImageMode, Settings},
   version::VERSION,
   REQWEST_TIMEOUT,
 };
-use percent_encoding::{utf8_percent_encode, NON_ALPHANUMERIC};
+use mime::Mime;
-use reqwest::{Client, ClientBuilder};
+use reqwest::{header::CONTENT_TYPE, Client, ClientBuilder};
 use reqwest_middleware::ClientWithMiddleware;
 use serde::Deserialize;
 use tracing::info;
 use url::Url;
+use urlencoding::encode;
 use webpage::HTML;
 
-/// Fetches the post link html tags (like title, description, image, etc)
+pub fn client_builder(settings: &Settings) -> ClientBuilder {
+  let user_agent = format!(
+    "Lemmy/{}; +{}",
+    VERSION,
+    settings.get_protocol_and_hostname()
+  );
+
+  Client::builder()
+    .user_agent(user_agent.clone())
+    .timeout(REQWEST_TIMEOUT)
+    .connect_timeout(REQWEST_TIMEOUT)
+}
+
+/// Fetches metadata for the given link and optionally generates thumbnail.
 #[tracing::instrument(skip_all)]
-pub async fn fetch_site_metadata(
+pub async fn fetch_link_metadata(
-  client: &ClientWithMiddleware,
   url: &Url,
-) -> Result<SiteMetadata, LemmyError> {
+  generate_thumbnail: bool,
+  context: &LemmyContext,
+) -> Result<LinkMetadata, LemmyError> {
   info!("Fetching site metadata for url: {}", url);
-  let response = client.get(url.as_str()).send().await?;
+  let response = context.client().get(url.as_str()).send().await?;
+
+  let content_type: Option<Mime> = response
+    .headers()
+    .get(CONTENT_TYPE)
+    .and_then(|h| h.to_str().ok())
+    .and_then(|h| h.parse().ok());
 
   // Can't use .text() here, because it only checks the content header, not the actual bytes
   // https://github.com/LemmyNet/lemmy/issues/1964
   let html_bytes = response.bytes().await.map_err(LemmyError::from)?.to_vec();
 
-  let tags = html_to_site_metadata(&html_bytes, url)?;
+  let opengraph_data = extract_opengraph_data(&html_bytes, url).unwrap_or_default();
+  let thumbnail = extract_thumbnail_from_opengraph_data(
+    url,
+    &opengraph_data,
+    &content_type,
+    generate_thumbnail,
+    context,
+  )
+  .await;
 
-  Ok(tags)
+  Ok(LinkMetadata {
+    opengraph_data,
+    content_type: content_type.map(|c| c.to_string()),
+    thumbnail,
+  })
 }
 
-fn html_to_site_metadata(html_bytes: &[u8], url: &Url) -> Result<SiteMetadata, LemmyError> {
+#[tracing::instrument(skip_all)]
+pub async fn fetch_link_metadata_opt(
+  url: Option<&Url>,
+  generate_thumbnail: bool,
+  context: &LemmyContext,
+) -> LinkMetadata {
+  match &url {
+    Some(url) => fetch_link_metadata(url, generate_thumbnail, context)
+      .await
+      .unwrap_or_default(),
+    _ => Default::default(),
+  }
+}
+
+/// Extract site metadata from HTML Opengraph attributes.
+fn extract_opengraph_data(html_bytes: &[u8], url: &Url) -> Result<OpenGraphData, LemmyError> {
   let html = String::from_utf8_lossy(html_bytes);
 
   // Make sure the first line is doctype html
@@ -89,7 +141,7 @@ fn html_to_site_metadata(html_bytes: &[u8], url: &Url) -> Result<SiteMetadata, L
     // join also works if the target URL is absolute
     .and_then(|v| url.join(&v.url).ok());
 
-  Ok(SiteMetadata {
+  Ok(OpenGraphData {
     title: og_title.or(page_title),
     description: og_description.or(page_description),
     image: og_image.map(Into::into),
@@ -97,59 +149,48 @@ fn html_to_site_metadata(html_bytes: &[u8], url: &Url) -> Result<SiteMetadata, L
   })
 }
 
-#[derive(Deserialize, Debug, Clone)]
+#[tracing::instrument(skip_all)]
-pub(crate) struct PictrsResponse {
+pub async fn extract_thumbnail_from_opengraph_data(
+  url: &Url,
+  opengraph_data: &OpenGraphData,
+  content_type: &Option<Mime>,
+  generate_thumbnail: bool,
+  context: &LemmyContext,
+) -> Option<DbUrl> {
+  let is_image = content_type.as_ref().unwrap_or(&mime::TEXT_PLAIN).type_() == mime::IMAGE;
+  if generate_thumbnail && is_image {
+    let image_url = opengraph_data
+      .image
+      .as_ref()
+      .map(lemmy_db_schema::newtypes::DbUrl::inner)
+      .unwrap_or(url);
+    generate_pictrs_thumbnail(image_url, context)
+      .await
+      .ok()
+      .map(Into::into)
+  } else {
+    None
+  }
+}
+
+#[derive(Deserialize, Debug)]
+struct PictrsResponse {
   files: Vec<PictrsFile>,
   msg: String,
 }
 
-#[derive(Deserialize, Debug, Clone)]
+#[derive(Deserialize, Debug)]
-pub(crate) struct PictrsFile {
+struct PictrsFile {
   file: String,
   #[allow(dead_code)]
   delete_token: String,
 }
 
-#[derive(Deserialize, Debug, Clone)]
+#[derive(Deserialize, Debug)]
-pub(crate) struct PictrsPurgeResponse {
+struct PictrsPurgeResponse {
   msg: String,
 }
 
-#[tracing::instrument(skip_all)]
-pub(crate) async fn fetch_pictrs(
-  client: &ClientWithMiddleware,
-  settings: &Settings,
-  image_url: &Url,
-) -> Result<PictrsResponse, LemmyError> {
-  let pictrs_config = settings.pictrs_config()?;
-  is_image_content_type(client, image_url).await?;
-
-  if pictrs_config.cache_external_link_previews {
-    // fetch remote non-pictrs images for persistent thumbnail link
-    let fetch_url = format!(
-      "{}image/download?url={}",
-      pictrs_config.url,
-      utf8_percent_encode(image_url.as_str(), NON_ALPHANUMERIC) // TODO this might not be needed
-    );
-
-    let response = client
-      .get(&fetch_url)
-      .timeout(REQWEST_TIMEOUT)
-      .send()
-      .await?;
-
-    let response: PictrsResponse = response.json().await.map_err(LemmyError::from)?;
-
-    if response.msg == "ok" {
-      Ok(response)
-    } else {
-      Err(LemmyErrorType::PictrsResponseError(response.msg))?
-    }
-  } else {
-    Err(LemmyErrorType::PictrsCachingDisabled)?
-  }
-}
-
 /// Purges an image from pictrs
 /// Note: This should often be coerced from a Result to .ok() in order to fail softly, because:
 /// - It might fail due to image being not local
@@ -167,13 +208,6 @@ pub async fn purge_image_from_pictrs(
     .next_back()
     .ok_or(LemmyErrorType::ImageUrlMissingLastPathSegment)?;
 
-  purge_image_from_pictrs_by_alias(alias, context).await
-}
-
-pub async fn purge_image_from_pictrs_by_alias(
-  alias: &str,
-  context: &LemmyContext,
-) -> Result<(), LemmyError> {
   let pictrs_config = context.settings().pictrs_config()?;
   let purge_url = format!("{}internal/purge?alias={}", pictrs_config.url, alias);
 
@@ -190,10 +224,9 @@ pub async fn purge_image_from_pictrs_by_alias(
 
   let response: PictrsPurgeResponse = response.json().await.map_err(LemmyError::from)?;
 
-  if response.msg == "ok" {
+  match response.msg.as_str() {
-    Ok(())
+    "ok" => Ok(()),
-  } else {
+    _ => Err(LemmyErrorType::PictrsPurgeResponseError(response.msg))?,
-    Err(LemmyErrorType::PictrsPurgeResponseError(response.msg))?
   }
 }
 
@@ -217,62 +250,48 @@ pub async fn delete_image_from_pictrs(
   Ok(())
 }
 
-/// Both are options, since the URL might be either an html page, or an image
+/// Retrieves the image with local pict-rs and generates a thumbnail. Returns the thumbnail url.
-/// Returns the SiteMetadata, and an image URL, if there is a picture associated
 #[tracing::instrument(skip_all)]
-pub async fn fetch_site_data(
+async fn generate_pictrs_thumbnail(
-  client: &ClientWithMiddleware,
+  image_url: &Url,
-  settings: &Settings,
+  context: &LemmyContext,
-  url: Option<&Url>,
+) -> Result<Url, LemmyError> {
-  include_image: bool,
+  let pictrs_config = context.settings().pictrs_config()?;
-) -> (Option<SiteMetadata>, Option<DbUrl>) {
+
-  match &url {
+  if pictrs_config.image_mode() == PictrsImageMode::ProxyAllImages {
-    Some(url) => {
+    return Ok(proxy_image_link(image_url.clone(), context).await?.into());
-      // Fetch metadata
-      // Ignore errors, since it may be an image, or not have the data.
-      // Warning, this may ignore SSL errors
-      let metadata_option = fetch_site_metadata(client, url).await.ok();
-      if !include_image {
-        (metadata_option, None)
-      } else {
-        let thumbnail_url =
-          fetch_pictrs_url_from_site_metadata(client, &metadata_option, settings, url)
-            .await
-            .ok();
-        (metadata_option, thumbnail_url)
-      }
-    }
-    None => (None, None),
-  }
   }
 
-async fn fetch_pictrs_url_from_site_metadata(
+  // fetch remote non-pictrs images for persistent thumbnail link
-  client: &ClientWithMiddleware,
+  // TODO: should limit size once supported by pictrs
-  metadata_option: &Option<SiteMetadata>,
+  let fetch_url = format!(
-  settings: &Settings,
+    "{}image/download?url={}",
-  url: &Url,
+    pictrs_config.url,
-) -> Result<DbUrl, LemmyError> {
+    encode(image_url.as_str())
-  let pictrs_res = match metadata_option {
+  );
-    Some(metadata_res) => match &metadata_res.image {
-      // Metadata, with image
-      // Try to generate a small thumbnail if there's a full sized one from post-links
-      Some(metadata_image) => fetch_pictrs(client, settings, metadata_image).await,
-      // Metadata, but no image
-      None => fetch_pictrs(client, settings, url).await,
-    },
-    // No metadata, try to fetch the URL as an image
-    None => fetch_pictrs(client, settings, url).await,
-  }?;
 
-  Url::parse(&format!(
+  let response = context
+    .client()
+    .get(&fetch_url)
+    .timeout(REQWEST_TIMEOUT)
+    .send()
+    .await?;
+
+  let response: PictrsResponse = response.json().await?;
+
+  if response.msg == "ok" {
+    let thumbnail_url = Url::parse(&format!(
       "{}/pictrs/image/{}",
-    settings.get_protocol_and_hostname(),
+      context.settings().get_protocol_and_hostname(),
-    pictrs_res.files.first().expect("missing pictrs file").file
+      response.files.first().expect("missing pictrs file").file
-  ))
+    ))?;
-  .map(Into::into)
+    Ok(thumbnail_url)
-  .map_err(Into::into)
+  } else {
+    Err(LemmyErrorType::PictrsResponseError(response.msg))?
+  }
 }
 
+// TODO: get rid of this by reading content type from db
 #[tracing::instrument(skip_all)]
 async fn is_image_content_type(client: &ClientWithMiddleware, url: &Url) -> Result<(), LemmyError> {
   let response = client.get(url.as_str()).send().await?;
@@ -289,51 +308,50 @@ async fn is_image_content_type(client: &ClientWithMiddleware, url: &Url) -> Resu
   }
 }
 
-pub fn client_builder(settings: &Settings) -> ClientBuilder {
-  let user_agent = format!(
-    "Lemmy/{}; +{}",
-    VERSION,
-    settings.get_protocol_and_hostname()
-  );
-
-  Client::builder()
-    .user_agent(user_agent)
-    .timeout(REQWEST_TIMEOUT)
-    .connect_timeout(REQWEST_TIMEOUT)
-}
-
 #[cfg(test)]
 mod tests {
   #![allow(clippy::unwrap_used)]
   #![allow(clippy::indexing_slicing)]
 
-  use crate::request::{client_builder, fetch_site_metadata, html_to_site_metadata, SiteMetadata};
+  use crate::{
-  use lemmy_utils::settings::SETTINGS;
+    context::LemmyContext,
+    request::{extract_opengraph_data, fetch_link_metadata},
+  };
   use pretty_assertions::assert_eq;
+  use serial_test::serial;
   use url::Url;
 
   // These helped with testing
   #[tokio::test]
-  async fn test_site_metadata() {
+  #[serial]
-    let settings = &SETTINGS.clone();
+  async fn test_link_metadata() {
-    let client = client_builder(settings).build().unwrap().into();
+    let context = LemmyContext::init_test_context_with_networking().await;
     let sample_url = Url::parse("https://gitlab.com/IzzyOnDroid/repo/-/wikis/FAQ").unwrap();
-    let sample_res = fetch_site_metadata(&client, &sample_url).await.unwrap();
+    let sample_res = fetch_link_metadata(&sample_url, false, &context)
+      .await
+      .unwrap();
     assert_eq!(
-      SiteMetadata {
+      Some("FAQ · Wiki · IzzyOnDroid / repo · GitLab".to_string()),
-        title: Some("FAQ · Wiki · IzzyOnDroid / repo · GitLab".to_string()),
+      sample_res.opengraph_data.title
-        description: Some(
+    );
-          "The F-Droid compatible repo at https://apt.izzysoft.de/fdroid/".to_string()
+    assert_eq!(
-        ),
+      Some("The F-Droid compatible repo at https://apt.izzysoft.de/fdroid/".to_string()),
-        image: Some(
+      sample_res.opengraph_data.description
+    );
+    assert_eq!(
+      Some(
         Url::parse("https://gitlab.com/uploads/-/system/project/avatar/4877469/iod_logo.png")
           .unwrap()
           .into()
       ),
-        embed_video_url: None,
+      sample_res.opengraph_data.image
-      },
-      sample_res
     );
+    assert_eq!(None, sample_res.opengraph_data.embed_video_url);
+    assert_eq!(
+      Some(mime::TEXT_HTML_UTF_8.to_string()),
+      sample_res.content_type
+    );
+    assert_eq!(None, sample_res.thumbnail);
   }
 
   // #[test]
@@ -351,7 +369,7 @@ mod tests {
 
     // root relative url
     let html_bytes = b"<!DOCTYPE html><html><head><meta property='og:image' content='/image.jpg'></head><body></body></html>";
-    let metadata = html_to_site_metadata(html_bytes, &url).expect("Unable to parse metadata");
+    let metadata = extract_opengraph_data(html_bytes, &url).expect("Unable to parse metadata");
     assert_eq!(
       metadata.image,
       Some(Url::parse("https://example.com/image.jpg").unwrap().into())
@@ -359,7 +377,7 @@ mod tests {
 
     // base relative url
     let html_bytes = b"<!DOCTYPE html><html><head><meta property='og:image' content='image.jpg'></head><body></body></html>";
-    let metadata = html_to_site_metadata(html_bytes, &url).expect("Unable to parse metadata");
+    let metadata = extract_opengraph_data(html_bytes, &url).expect("Unable to parse metadata");
     assert_eq!(
       metadata.image,
       Some(
@@ -371,7 +389,7 @@ mod tests {
 
     // absolute url
     let html_bytes = b"<!DOCTYPE html><html><head><meta property='og:image' content='https://cdn.host.com/image.jpg'></head><body></body></html>";
-    let metadata = html_to_site_metadata(html_bytes, &url).expect("Unable to parse metadata");
+    let metadata = extract_opengraph_data(html_bytes, &url).expect("Unable to parse metadata");
     assert_eq!(
       metadata.image,
       Some(Url::parse("https://cdn.host.com/image.jpg").unwrap().into())
@@ -379,7 +397,7 @@ mod tests {
 
     // protocol relative url
     let html_bytes = b"<!DOCTYPE html><html><head><meta property='og:image' content='//example.com/image.jpg'></head><body></body></html>";
-    let metadata = html_to_site_metadata(html_bytes, &url).expect("Unable to parse metadata");
+    let metadata = extract_opengraph_data(html_bytes, &url).expect("Unable to parse metadata");
     assert_eq!(
       metadata.image,
       Some(Url::parse("https://example.com/image.jpg").unwrap().into())

crates/api_common/src/utils.rs

@@ -12,6 +12,7 @@ use lemmy_db_schema::{
     community::{Community, CommunityModerator, CommunityUpdateForm},
     community_block::CommunityBlock,
     email_verification::{EmailVerification, EmailVerificationForm},
+    images::RemoteImage,
     instance::Instance,
     instance_block::InstanceBlock,
     local_site::LocalSite,
@@ -35,14 +36,18 @@ use lemmy_utils::{
   email::{send_email, translations::Lang},
   error::{LemmyError, LemmyErrorExt, LemmyErrorType, LemmyResult},
   rate_limit::{ActionType, BucketConfig},
-  settings::structs::Settings,
+  settings::structs::{PictrsImageMode, Settings},
-  utils::slurs::build_slur_regex,
+  utils::{
+    markdown::markdown_rewrite_image_links,
+    slurs::{build_slur_regex, remove_slurs},
+  },
 };
 use regex::Regex;
 use rosetta_i18n::{Language, LanguageId};
 use std::collections::HashSet;
 use tracing::warn;
 use url::{ParseError, Url};
+use urlencoding::encode;
 
 pub static AUTH_COOKIE_NAME: &str = "jwt";
 
@@ -848,14 +853,115 @@ fn limit_expire_time(expires: DateTime<Utc>) -> LemmyResult<Option<DateTime<Utc>
   }
 }
 
+pub async fn process_markdown(
+  text: &str,
+  slur_regex: &Option<Regex>,
+  context: &LemmyContext,
+) -> LemmyResult<String> {
+  let text = remove_slurs(text, slur_regex);
+  if context.settings().pictrs_config()?.image_mode() == PictrsImageMode::ProxyAllImages {
+    let (text, links) = markdown_rewrite_image_links(text);
+    RemoteImage::create(&mut context.pool(), links).await?;
+    Ok(text)
+  } else {
+    Ok(text)
+  }
+}
+
+pub async fn process_markdown_opt(
+  text: &Option<String>,
+  slur_regex: &Option<Regex>,
+  context: &LemmyContext,
+) -> LemmyResult<Option<String>> {
+  match text {
+    Some(t) => process_markdown(t, slur_regex, context).await.map(Some),
+    None => Ok(None),
+  }
+}
+
+/// A wrapper for `proxy_image_link` for use in tests.
+///
+/// The parameter `force_image_proxy` is the config value of `pictrs.image_proxy`. Its necessary to pass
+/// as separate parameter so it can be changed in tests.
+async fn proxy_image_link_internal(
+  link: Url,
+  image_mode: PictrsImageMode,
+  context: &LemmyContext,
+) -> LemmyResult<DbUrl> {
+  // Dont rewrite links pointing to local domain.
+  if link.domain() == Some(&context.settings().hostname) {
+    Ok(link.into())
+  } else if image_mode == PictrsImageMode::ProxyAllImages {
+    let proxied = format!(
+      "{}/api/v3/image_proxy?url={}",
+      context.settings().get_protocol_and_hostname(),
+      encode(link.as_str())
+    );
+    RemoteImage::create(&mut context.pool(), vec![link]).await?;
+    Ok(Url::parse(&proxied)?.into())
+  } else {
+    Ok(link.into())
+  }
+}
+
+/// Rewrite a link to go through `/api/v3/image_proxy` endpoint. This is only for remote urls and
+/// if image_proxy setting is enabled.
+pub(crate) async fn proxy_image_link(link: Url, context: &LemmyContext) -> LemmyResult<DbUrl> {
+  proxy_image_link_internal(
+    link,
+    context.settings().pictrs_config()?.image_mode(),
+    context,
+  )
+  .await
+}
+
+pub async fn proxy_image_link_opt_api(
+  link: &Option<String>,
+  context: &LemmyContext,
+) -> LemmyResult<Option<Option<DbUrl>>> {
+  proxy_image_link_api(link, context).await.map(Some)
+}
+
+pub async fn proxy_image_link_api(
+  link: &Option<String>,
+  context: &LemmyContext,
+) -> LemmyResult<Option<DbUrl>> {
+  let link: Option<DbUrl> = match link.as_ref().map(String::as_str) {
+    // An empty string is an erase
+    Some("") => None,
+    Some(str_url) => Url::parse(str_url)
+      .map(|u| Some(u.into()))
+      .with_lemmy_type(LemmyErrorType::InvalidUrl)?,
+    None => None,
+  };
+  if let Some(l) = link {
+    proxy_image_link(l.into(), context).await.map(Some)
+  } else {
+    Ok(link)
+  }
+}
+
+pub async fn proxy_image_link_opt_apub(
+  link: Option<Url>,
+  context: &LemmyContext,
+) -> LemmyResult<Option<DbUrl>> {
+  if let Some(l) = link {
+    proxy_image_link(l, context).await.map(Some)
+  } else {
+    Ok(None)
+  }
+}
+
 #[cfg(test)]
 mod tests {
   #![allow(clippy::unwrap_used)]
   #![allow(clippy::indexing_slicing)]
 
+  use super::*;
   use crate::utils::{honeypot_check, limit_expire_time, password_length_check};
   use chrono::{Days, Utc};
   use pretty_assertions::assert_eq;
+  use serial_test::serial;
 
   #[test]
   #[rustfmt::skip]
@@ -894,4 +1000,62 @@ mod tests {
       None
     );
   }
+
+  #[tokio::test]
+  #[serial]
+  async fn test_proxy_image_link() {
+    let context = LemmyContext::init_test_context().await;
+
+    // image from local domain is unchanged
+    let local_url = Url::parse("http://lemmy-alpha/image.png").unwrap();
+    let proxied =
+      proxy_image_link_internal(local_url.clone(), PictrsImageMode::ProxyAllImages, &context)
+        .await
+        .unwrap();
+    assert_eq!(&local_url, proxied.inner());
+
+    // image from remote domain is proxied
+    let remote_image = Url::parse("http://lemmy-beta/image.png").unwrap();
+    let proxied = proxy_image_link_internal(
+      remote_image.clone(),
+      PictrsImageMode::ProxyAllImages,
+      &context,
+    )
+    .await
+    .unwrap();
+    assert_eq!(
+      "https://lemmy-alpha/api/v3/image_proxy?url=http%3A%2F%2Flemmy-beta%2Fimage.png",
+      proxied.as_str()
+    );
+    assert!(
+      RemoteImage::validate(&mut context.pool(), remote_image.into())
+        .await
+        .is_ok()
+    );
+  }
+
+  #[tokio::test]
+  #[serial]
+  async fn test_diesel_option_overwrite_to_url() {
+    let context = LemmyContext::init_test_context().await;
+
+    assert!(matches!(
+      proxy_image_link_api(&None, &context).await,
+      Ok(None)
+    ));
+    assert!(matches!(
+      proxy_image_link_opt_api(&Some(String::new()), &context).await,
+      Ok(Some(None))
+    ));
+    assert!(
+      proxy_image_link_opt_api(&Some("invalid_url".to_string()), &context)
+        .await
+        .is_err()
+    );
+    let example_url = "https://lemmy-alpha/image.png";
+    assert!(matches!(
+      proxy_image_link_opt_api(&Some(example_url.to_string()), &context).await,
+      Ok(Some(Some(url))) if url == Url::parse(example_url).unwrap().into()
+    ));
+  }
 }

crates/api_crud/src/comment/create.rs

@@ -11,6 +11,7 @@ use lemmy_api_common::{
     generate_local_apub_endpoint,
     get_post,
     local_site_to_slur_regex,
+    process_markdown,
     EndpointType,
   },
 };
@@ -28,11 +29,7 @@ use lemmy_db_schema::{
 use lemmy_db_views::structs::LocalUserView;
 use lemmy_utils::{
   error::{LemmyError, LemmyErrorExt, LemmyErrorType},
-  utils::{
+  utils::{mention::scrape_text_for_mentions, validation::is_valid_body_field},
-    mention::scrape_text_for_mentions,
-    slurs::remove_slurs,
-    validation::is_valid_body_field,
-  },
 };
 
 const MAX_COMMENT_DEPTH_LIMIT: usize = 100;
@@ -45,10 +42,8 @@ pub async fn create_comment(
 ) -> Result<Json<CommentResponse>, LemmyError> {
   let local_site = LocalSite::read(&mut context.pool()).await?;
 
-  let content = remove_slurs(
+  let slur_regex = local_site_to_slur_regex(&local_site);
-    &data.content.clone(),
+  let content = process_markdown(&data.content, &slur_regex, &context).await?;
-    &local_site_to_slur_regex(&local_site),
-  );
   is_valid_body_field(&Some(content.clone()), false)?;
 
   // Check for a community ban

crates/api_crud/src/comment/update.rs

@@ -5,7 +5,7 @@ use lemmy_api_common::{
   comment::{CommentResponse, EditComment},
   context::LemmyContext,
   send_activity::{ActivityChannel, SendActivityData},
-  utils::{check_community_user_action, local_site_to_slur_regex},
+  utils::{check_community_user_action, local_site_to_slur_regex, process_markdown_opt},
 };
 use lemmy_db_schema::{
   source::{
@@ -19,11 +19,7 @@ use lemmy_db_schema::{
 use lemmy_db_views::structs::{CommentView, LocalUserView};
 use lemmy_utils::{
   error::{LemmyError, LemmyErrorExt, LemmyErrorType},
-  utils::{
+  utils::{mention::scrape_text_for_mentions, validation::is_valid_body_field},
-    mention::scrape_text_for_mentions,
-    slurs::remove_slurs,
-    validation::is_valid_body_field,
-  },
 };
 
 #[tracing::instrument(skip(context))]
@@ -57,11 +53,8 @@ pub async fn update_comment(
   )
   .await?;
 
-  // Update the Content
+  let slur_regex = local_site_to_slur_regex(&local_site);
-  let content = data
+  let content = process_markdown_opt(&data.content, &slur_regex, &context).await?;
-    .content
-    .as_ref()
-    .map(|c| remove_slurs(c, &local_site_to_slur_regex(&local_site)));
   is_valid_body_field(&content, false)?;
 
   let comment_id = data.comment_id;

crates/api_crud/src/community/create.rs

@@ -11,6 +11,8 @@ use lemmy_api_common::{
     generate_shared_inbox_url,
     is_admin,
     local_site_to_slur_regex,
+    process_markdown_opt,
+    proxy_image_link_api,
     EndpointType,
   },
 };
@@ -27,13 +29,12 @@ use lemmy_db_schema::{
     },
   },
   traits::{ApubActor, Crud, Followable, Joinable},
-  utils::diesel_option_overwrite_to_url_create,
 };
 use lemmy_db_views::structs::{LocalUserView, SiteView};
 use lemmy_utils::{
   error::{LemmyError, LemmyErrorExt, LemmyErrorType},
   utils::{
-    slurs::{check_slurs, check_slurs_opt},
+    slurs::check_slurs,
     validation::{is_valid_actor_name, is_valid_body_field},
   },
 };
@@ -51,14 +52,12 @@ pub async fn create_community(
     Err(LemmyErrorType::OnlyAdminsCanCreateCommunities)?
   }
 
-  // Check to make sure the icon and banners are urls
-  let icon = diesel_option_overwrite_to_url_create(&data.icon)?;
-  let banner = diesel_option_overwrite_to_url_create(&data.banner)?;
-
   let slur_regex = local_site_to_slur_regex(&local_site);
   check_slurs(&data.name, &slur_regex)?;
   check_slurs(&data.title, &slur_regex)?;
-  check_slurs_opt(&data.description, &slur_regex)?;
+  let description = process_markdown_opt(&data.description, &slur_regex, &context).await?;
+  let icon = proxy_image_link_api(&data.icon, &context).await?;
+  let banner = proxy_image_link_api(&data.banner, &context).await?;
 
   is_valid_actor_name(&data.name, local_site.actor_name_max_length as usize)?;
   is_valid_body_field(&data.description, false)?;
@@ -81,7 +80,7 @@ pub async fn create_community(
   let community_form = CommunityInsertForm::builder()
     .name(data.name.clone())
     .title(data.title.clone())
-    .description(data.description.clone())
+    .description(description)
     .icon(icon)
     .banner(banner)
     .nsfw(data.nsfw)

crates/api_crud/src/community/update.rs

@@ -5,7 +5,12 @@ use lemmy_api_common::{
   community::{CommunityResponse, EditCommunity},
   context::LemmyContext,
   send_activity::{ActivityChannel, SendActivityData},
-  utils::{check_community_mod_action, local_site_to_slur_regex},
+  utils::{
+    check_community_mod_action,
+    local_site_to_slur_regex,
+    process_markdown_opt,
+    proxy_image_link_opt_api,
+  },
 };
 use lemmy_db_schema::{
   source::{
@@ -14,7 +19,7 @@ use lemmy_db_schema::{
     local_site::LocalSite,
   },
   traits::Crud,
-  utils::{diesel_option_overwrite, diesel_option_overwrite_to_url, naive_now},
+  utils::{diesel_option_overwrite, naive_now},
 };
 use lemmy_db_views::structs::LocalUserView;
 use lemmy_utils::{
@@ -32,12 +37,12 @@ pub async fn update_community(
 
   let slur_regex = local_site_to_slur_regex(&local_site);
   check_slurs_opt(&data.title, &slur_regex)?;
-  check_slurs_opt(&data.description, &slur_regex)?;
+  let description = process_markdown_opt(&data.description, &slur_regex, &context).await?;
   is_valid_body_field(&data.description, false)?;
 
-  let icon = diesel_option_overwrite_to_url(&data.icon)?;
+  let description = diesel_option_overwrite(description);
-  let banner = diesel_option_overwrite_to_url(&data.banner)?;
+  let icon = proxy_image_link_opt_api(&data.icon, &context).await?;
-  let description = diesel_option_overwrite(data.description.clone());
+  let banner = proxy_image_link_opt_api(&data.banner, &context).await?;
 
   // Verify its a mod (only mods can edit it)
   check_community_mod_action(

crates/api_crud/src/post/create.rs

@@ -4,7 +4,7 @@ use lemmy_api_common::{
   build_response::build_post_response,
   context::LemmyContext,
   post::{CreatePost, PostResponse},
-  request::fetch_site_data,
+  request::fetch_link_metadata_opt,
   send_activity::{ActivityChannel, SendActivityData},
   utils::{
     check_community_user_action,
@@ -12,6 +12,8 @@ use lemmy_api_common::{
     honeypot_check,
     local_site_to_slur_regex,
     mark_post_as_read,
+    process_markdown_opt,
+    proxy_image_link_opt_apub,
     EndpointType,
   },
 };
@@ -31,7 +33,7 @@ use lemmy_utils::{
   error::{LemmyError, LemmyErrorExt, LemmyErrorType},
   spawn_try_task,
   utils::{
-    slurs::{check_slurs, check_slurs_opt},
+    slurs::check_slurs,
     validation::{check_url_scheme, clean_url_params, is_valid_body_field, is_valid_post_title},
   },
 };
@@ -49,14 +51,14 @@ pub async fn create_post(
 
   let slur_regex = local_site_to_slur_regex(&local_site);
   check_slurs(&data.name, &slur_regex)?;
-  check_slurs_opt(&data.body, &slur_regex)?;
+  let body = process_markdown_opt(&data.body, &slur_regex, &context).await?;
   honeypot_check(&data.honeypot)?;
 
   let data_url = data.url.as_ref();
-  let url = data_url.map(clean_url_params).map(Into::into); // TODO no good way to handle a "clear"
+  let url = data_url.map(clean_url_params); // TODO no good way to handle a "clear"
 
   is_valid_post_title(&data.name)?;
-  is_valid_body_field(&data.body, true)?;
+  is_valid_body_field(&body, true)?;
   check_url_scheme(&data.url)?;
 
   check_community_user_action(
@@ -82,11 +84,8 @@ pub async fn create_post(
   }
 
   // Fetch post links and pictrs cached image
-  let (metadata_res, thumbnail_url) =
+  let metadata = fetch_link_metadata_opt(url.as_ref(), true, &context).await;
-    fetch_site_data(context.client(), context.settings(), data_url, true).await;
+  let url = proxy_image_link_opt_apub(url, &context).await?;
-  let (embed_title, embed_description, embed_video_url) = metadata_res
-    .map(|u| (u.title, u.description, u.embed_video_url))
-    .unwrap_or_default();
 
   // Only need to check if language is allowed in case user set it explicitly. When using default
   // language, it already only returns allowed languages.
@@ -113,15 +112,15 @@ pub async fn create_post(
   let post_form = PostInsertForm::builder()
     .name(data.name.trim().to_string())
     .url(url)
-    .body(data.body.clone())
+    .body(body)
     .community_id(data.community_id)
     .creator_id(local_user_view.person.id)
     .nsfw(data.nsfw)
-    .embed_title(embed_title)
+    .embed_title(metadata.opengraph_data.title)
-    .embed_description(embed_description)
+    .embed_description(metadata.opengraph_data.description)
-    .embed_video_url(embed_video_url)
+    .embed_video_url(metadata.opengraph_data.embed_video_url)
     .language_id(language_id)
-    .thumbnail_url(thumbnail_url)
+    .thumbnail_url(metadata.thumbnail)
     .build();
 
   let inserted_post = Post::create(&mut context.pool(), &post_form)

crates/api_crud/src/post/update.rs

@@ -4,9 +4,14 @@ use lemmy_api_common::{
   build_response::build_post_response,
   context::LemmyContext,
   post::{EditPost, PostResponse},
-  request::fetch_site_data,
+  request::fetch_link_metadata,
   send_activity::{ActivityChannel, SendActivityData},
-  utils::{check_community_user_action, local_site_to_slur_regex},
+  utils::{
+    check_community_user_action,
+    local_site_to_slur_regex,
+    process_markdown_opt,
+    proxy_image_link_opt_apub,
+  },
 };
 use lemmy_db_schema::{
   source::{
@@ -35,21 +40,19 @@ pub async fn update_post(
 ) -> Result<Json<PostResponse>, LemmyError> {
   let local_site = LocalSite::read(&mut context.pool()).await?;
 
-  let data_url = data.url.as_ref();
-
   // TODO No good way to handle a clear.
   // Issue link: https://github.com/LemmyNet/lemmy/issues/2287
-  let url = Some(data_url.map(clean_url_params).map(Into::into));
+  let url = data.url.as_ref().map(clean_url_params);
 
   let slur_regex = local_site_to_slur_regex(&local_site);
   check_slurs_opt(&data.name, &slur_regex)?;
-  check_slurs_opt(&data.body, &slur_regex)?;
+  let body = process_markdown_opt(&data.body, &slur_regex, &context).await?;
 
   if let Some(name) = &data.name {
     is_valid_post_title(name)?;
   }
 
-  is_valid_body_field(&data.body, true)?;
+  is_valid_body_field(&body, true)?;
   check_url_scheme(&data.url)?;
 
   let post_id = data.post_id;
@@ -67,13 +70,23 @@ pub async fn update_post(
     Err(LemmyErrorType::NoPostEditAllowed)?
   }
 
-  // Fetch post links and Pictrs cached image
+  // Fetch post links and Pictrs cached image if url was updated
-  let data_url = data.url.as_ref();
+  let (embed_title, embed_description, embed_video_url, thumbnail_url) = match &url {
-  let (metadata_res, thumbnail_url) =
+    Some(url) => {
-    fetch_site_data(context.client(), context.settings(), data_url, true).await;
+      let metadata = fetch_link_metadata(url, true, &context).await?;
-  let (embed_title, embed_description, embed_video_url) = metadata_res
+      (
-    .map(|u| (Some(u.title), Some(u.description), Some(u.embed_video_url)))
+        Some(metadata.opengraph_data.title),
-    .unwrap_or_default();
+        Some(metadata.opengraph_data.description),
+        Some(metadata.opengraph_data.embed_video_url),
+        Some(metadata.thumbnail),
+      )
+    }
+    _ => Default::default(),
+  };
+  let url = match url {
+    Some(url) => Some(proxy_image_link_opt_apub(Some(url), &context).await?),
+    _ => Default::default(),
+  };
 
   let language_id = data.language_id;
   CommunityLanguage::is_allowed_community_language(
@@ -86,13 +99,13 @@ pub async fn update_post(
   let post_form = PostUpdateForm {
     name: data.name.clone(),
     url,
-    body: diesel_option_overwrite(data.body.clone()),
+    body: diesel_option_overwrite(body),
     nsfw: data.nsfw,
     embed_title,
     embed_description,
     embed_video_url,
     language_id: data.language_id,
-    thumbnail_url: Some(thumbnail_url),
+    thumbnail_url,
     updated: Some(Some(naive_now())),
     ..Default::default()
   };

crates/api_crud/src/private_message/create.rs

@@ -9,6 +9,7 @@ use lemmy_api_common::{
     generate_local_apub_endpoint,
     get_interface_language,
     local_site_to_slur_regex,
+    process_markdown,
     send_email_to_user,
     EndpointType,
   },
@@ -23,7 +24,7 @@ use lemmy_db_schema::{
 use lemmy_db_views::structs::{LocalUserView, PrivateMessageView};
 use lemmy_utils::{
   error::{LemmyError, LemmyErrorExt, LemmyErrorType},
-  utils::{markdown::markdown_to_html, slurs::remove_slurs, validation::is_valid_body_field},
+  utils::{markdown::markdown_to_html, validation::is_valid_body_field},
 };
 
 #[tracing::instrument(skip(context))]
@@ -34,7 +35,8 @@ pub async fn create_private_message(
 ) -> Result<Json<PrivateMessageResponse>, LemmyError> {
   let local_site = LocalSite::read(&mut context.pool()).await?;
 
-  let content = remove_slurs(&data.content, &local_site_to_slur_regex(&local_site));
+  let slur_regex = local_site_to_slur_regex(&local_site);
+  let content = process_markdown(&data.content, &slur_regex, &context).await?;
   is_valid_body_field(&Some(content.clone()), false)?;
 
   check_person_block(

crates/api_crud/src/private_message/update.rs

@@ -4,7 +4,7 @@ use lemmy_api_common::{
   context::LemmyContext,
   private_message::{EditPrivateMessage, PrivateMessageResponse},
   send_activity::{ActivityChannel, SendActivityData},
-  utils::local_site_to_slur_regex,
+  utils::{local_site_to_slur_regex, process_markdown},
 };
 use lemmy_db_schema::{
   source::{
@@ -17,7 +17,7 @@ use lemmy_db_schema::{
 use lemmy_db_views::structs::{LocalUserView, PrivateMessageView};
 use lemmy_utils::{
   error::{LemmyError, LemmyErrorExt, LemmyErrorType},
-  utils::{slurs::remove_slurs, validation::is_valid_body_field},
+  utils::validation::is_valid_body_field,
 };
 
 #[tracing::instrument(skip(context))]
@@ -36,7 +36,8 @@ pub async fn update_private_message(
   }
 
   // Doing the update
-  let content = remove_slurs(&data.content, &local_site_to_slur_regex(&local_site));
+  let slur_regex = local_site_to_slur_regex(&local_site);
+  let content = process_markdown(&data.content, &slur_regex, &context).await?;
   is_valid_body_field(&Some(content.clone()), false)?;
 
   let private_message_id = data.private_message_id;

crates/api_crud/src/site/create.rs

@@ -4,7 +4,14 @@ use actix_web::web::{Data, Json};
 use lemmy_api_common::{
   context::LemmyContext,
   site::{CreateSite, SiteResponse},
-  utils::{generate_shared_inbox_url, is_admin, local_site_rate_limit_to_rate_limit_config},
+  utils::{
+    generate_shared_inbox_url,
+    is_admin,
+    local_site_rate_limit_to_rate_limit_config,
+    local_site_to_slur_regex,
+    process_markdown_opt,
+    proxy_image_link_opt_api,
+  },
 };
 use lemmy_db_schema::{
   newtypes::DbUrl,
@@ -15,7 +22,7 @@ use lemmy_db_schema::{
     tagline::Tagline,
   },
   traits::Crud,
-  utils::{diesel_option_overwrite, diesel_option_overwrite_to_url, naive_now},
+  utils::{diesel_option_overwrite, naive_now},
 };
 use lemmy_db_views::structs::{LocalUserView, SiteView};
 use lemmy_utils::{
@@ -50,12 +57,17 @@ pub async fn create_site(
   let inbox_url = Some(generate_shared_inbox_url(context.settings())?);
   let keypair = generate_actor_keypair()?;
 
+  let slur_regex = local_site_to_slur_regex(&local_site);
+  let sidebar = process_markdown_opt(&data.sidebar, &slur_regex, &context).await?;
+  let icon = proxy_image_link_opt_api(&data.icon, &context).await?;
+  let banner = proxy_image_link_opt_api(&data.banner, &context).await?;
+
   let site_form = SiteUpdateForm {
     name: Some(data.name.clone()),
-    sidebar: diesel_option_overwrite(data.sidebar.clone()),
+    sidebar: diesel_option_overwrite(sidebar),
     description: diesel_option_overwrite(data.description.clone()),
-    icon: diesel_option_overwrite_to_url(&data.icon)?,
+    icon,
-    banner: diesel_option_overwrite_to_url(&data.banner)?,
+    banner,
     actor_id: Some(actor_id),
     last_refreshed_at: Some(naive_now()),
     inbox_url,

crates/api_crud/src/site/update.rs

@@ -3,7 +3,13 @@ use actix_web::web::{Data, Json};
 use lemmy_api_common::{
   context::LemmyContext,
   site::{EditSite, SiteResponse},
-  utils::{is_admin, local_site_rate_limit_to_rate_limit_config},
+  utils::{
+    is_admin,
+    local_site_rate_limit_to_rate_limit_config,
+    local_site_to_slur_regex,
+    process_markdown_opt,
+    proxy_image_link_opt_api,
+  },
 };
 use lemmy_db_schema::{
   source::{
@@ -17,7 +23,7 @@ use lemmy_db_schema::{
     tagline::Tagline,
   },
   traits::Crud,
-  utils::{diesel_option_overwrite, diesel_option_overwrite_to_url, naive_now},
+  utils::{diesel_option_overwrite, naive_now},
   RegistrationMode,
 };
 use lemmy_db_views::structs::{LocalUserView, SiteView};
@@ -54,12 +60,17 @@ pub async fn update_site(
     SiteLanguage::update(&mut context.pool(), discussion_languages.clone(), &site).await?;
   }
 
+  let slur_regex = local_site_to_slur_regex(&local_site);
+  let sidebar = process_markdown_opt(&data.sidebar, &slur_regex, &context).await?;
+  let icon = proxy_image_link_opt_api(&data.icon, &context).await?;
+  let banner = proxy_image_link_opt_api(&data.banner, &context).await?;
+
   let site_form = SiteUpdateForm {
     name: data.name.clone(),
-    sidebar: diesel_option_overwrite(data.sidebar.clone()),
+    sidebar: diesel_option_overwrite(sidebar),
     description: diesel_option_overwrite(data.description.clone()),
-    icon: diesel_option_overwrite_to_url(&data.icon)?,
+    icon,
-    banner: diesel_option_overwrite_to_url(&data.banner)?,
+    banner,
     updated: Some(Some(naive_now())),
     ..Default::default()
   };

crates/apub/Cargo.toml

@@ -50,7 +50,5 @@ enum_delegate = "0.2.0"
 
 [dev-dependencies]
 serial_test = { workspace = true }
-reqwest-middleware = { workspace = true }
-task-local-extensions = "0.1.4"
 assert-json-diff = "2.0.2"
 pretty_assertions = { workspace = true }

crates/apub/src/activities/community/update.rs

@@ -8,7 +8,7 @@ use crate::{
   },
   activity_lists::AnnouncableActivities,
   insert_received_activity,
-  objects::{community::ApubCommunity, person::ApubPerson},
+  objects::{community::ApubCommunity, person::ApubPerson, read_from_string_or_source_opt},
   protocol::{activities::community::update::UpdateCommunity, InCommunity},
 };
 use activitypub_federation::{
@@ -18,8 +18,13 @@ use activitypub_federation::{
 };
 use lemmy_api_common::context::LemmyContext;
 use lemmy_db_schema::{
-  source::{activity::ActivitySendTargets, community::Community, person::Person},
+  source::{
+    activity::ActivitySendTargets,
+    community::{Community, CommunityUpdateForm},
+    person::Person,
+  },
   traits::Crud,
+  utils::naive_now,
 };
 use lemmy_utils::error::LemmyError;
 use url::Url;
@@ -85,7 +90,33 @@ impl ActivityHandler for UpdateCommunity {
     insert_received_activity(&self.id, context).await?;
     let community = self.community(context).await?;
 
-    let community_update_form = self.object.into_update_form();
+    let community_update_form = CommunityUpdateForm {
+      title: Some(self.object.name.unwrap_or(self.object.preferred_username)),
+      description: Some(read_from_string_or_source_opt(
+        &self.object.summary,
+        &None,
+        &self.object.source,
+      )),
+      removed: None,
+      published: self.object.published.map(Into::into),
+      updated: Some(self.object.updated.map(Into::into)),
+      deleted: None,
+      nsfw: Some(self.object.sensitive.unwrap_or(false)),
+      actor_id: Some(self.object.id.into()),
+      local: None,
+      private_key: None,
+      hidden: None,
+      public_key: Some(self.object.public_key.public_key_pem),
+      last_refreshed_at: Some(naive_now()),
+      icon: Some(self.object.icon.map(|i| i.url.into())),
+      banner: Some(self.object.image.map(|i| i.url.into())),
+      followers_url: Some(self.object.followers.into()),
+      inbox_url: Some(self.object.inbox.into()),
+      shared_inbox_url: Some(self.object.endpoints.map(|e| e.shared_inbox.into())),
+      moderators_url: self.object.attributed_to.map(Into::into),
+      posting_restricted_to_mods: self.object.posting_restricted_to_mods,
+      featured_url: self.object.featured.map(Into::into),
+    };
 
     Community::update(&mut context.pool(), community.id, &community_update_form).await?;
     Ok(())

crates/apub/src/api/user_settings_backup.rs

@@ -298,10 +298,7 @@ pub async fn import_settings(
 mod tests {
   #![allow(clippy::indexing_slicing)]
 
-  use crate::{
+  use crate::api::user_settings_backup::{export_settings, import_settings};
-    api::user_settings_backup::{export_settings, import_settings},
-    objects::tests::init_context,
-  };
   use activitypub_federation::config::Data;
   use lemmy_api_common::context::LemmyContext;
   use lemmy_db_schema::{
@@ -348,7 +345,7 @@ mod tests {
   #[tokio::test]
   #[serial]
   async fn test_settings_export_import() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
 
     let export_user =
       create_user("hanna".to_string(), Some("my bio".to_string()), &context).await?;
@@ -397,7 +394,7 @@ mod tests {
   #[tokio::test]
   #[serial]
   async fn disallow_large_backup() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
 
     let export_user =
       create_user("hanna".to_string(), Some("my bio".to_string()), &context).await?;

crates/apub/src/collections/community_moderators.rs

@@ -106,11 +106,7 @@ mod tests {
 
   use super::*;
   use crate::{
-    objects::{
+    objects::{community::tests::parse_lemmy_community, person::tests::parse_lemmy_person},
-      community::tests::parse_lemmy_community,
-      person::tests::parse_lemmy_person,
-      tests::init_context,
-    },
     protocol::tests::file_to_json_object,
   };
   use lemmy_db_schema::{
@@ -129,7 +125,7 @@ mod tests {
   #[tokio::test]
   #[serial]
   async fn test_parse_lemmy_community_moderators() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
     let (new_mod, site) = parse_lemmy_person(&context).await?;
     let community = parse_lemmy_community(&context).await?;
     let community_id = community.id;

crates/apub/src/objects/comment.rs

@@ -16,7 +16,10 @@ use activitypub_federation::{
   traits::Object,
 };
 use chrono::{DateTime, Utc};
-use lemmy_api_common::{context::LemmyContext, utils::local_site_opt_to_slur_regex};
+use lemmy_api_common::{
+  context::LemmyContext,
+  utils::{local_site_opt_to_slur_regex, process_markdown},
+};
 use lemmy_db_schema::{
   source::{
     comment::{Comment, CommentInsertForm, CommentUpdateForm},
@@ -29,7 +32,7 @@ use lemmy_db_schema::{
 };
 use lemmy_utils::{
   error::{LemmyError, LemmyErrorType},
-  utils::{markdown::markdown_to_html, slurs::remove_slurs},
+  utils::markdown::markdown_to_html,
 };
 use std::ops::Deref;
 use url::Url;
@@ -158,7 +161,7 @@ impl Object for ApubComment {
 
     let local_site = LocalSite::read(&mut context.pool()).await.ok();
     let slur_regex = &local_site_opt_to_slur_regex(&local_site);
-    let content = remove_slurs(&content, slur_regex);
+    let content = process_markdown(&content, slur_regex, context).await?;
     let language_id =
       LanguageTag::to_language_id_single(note.language, &mut context.pool()).await?;
 
@@ -190,7 +193,6 @@ pub(crate) mod tests {
       instance::ApubSite,
       person::{tests::parse_lemmy_person, ApubPerson},
       post::ApubPost,
-      tests::init_context,
     },
     protocol::tests::file_to_json_object,
   };
@@ -230,7 +232,7 @@ pub(crate) mod tests {
   #[tokio::test]
   #[serial]
   pub(crate) async fn test_parse_lemmy_comment() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
     let url = Url::parse("https://enterprise.lemmy.ml/comment/38741")?;
     let data = prepare_comment_test(&url, &context).await?;
 
@@ -255,7 +257,7 @@ pub(crate) mod tests {
   #[tokio::test]
   #[serial]
   async fn test_parse_pleroma_comment() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
     let url = Url::parse("https://enterprise.lemmy.ml/comment/38741")?;
     let data = prepare_comment_test(&url, &context).await?;
 

crates/apub/src/objects/community.rs

@@ -2,7 +2,7 @@ use crate::{
   activities::GetActorType,
   check_apub_id_valid,
   local_site_data_cached,
-  objects::instance::fetch_instance_actor_for_object,
+  objects::{instance::fetch_instance_actor_for_object, read_from_string_or_source_opt},
   protocol::{
     objects::{group::Group, Endpoints, LanguageTag},
     ImageObject,
@@ -17,15 +17,24 @@ use activitypub_federation::{
 use chrono::{DateTime, Utc};
 use lemmy_api_common::{
   context::LemmyContext,
-  utils::{generate_featured_url, generate_moderators_url, generate_outbox_url},
+  utils::{
+    generate_featured_url,
+    generate_moderators_url,
+    generate_outbox_url,
+    local_site_opt_to_slur_regex,
+    process_markdown_opt,
+    proxy_image_link_opt_apub,
+  },
 };
 use lemmy_db_schema::{
   source::{
     activity::ActorType,
     actor_language::CommunityLanguage,
-    community::{Community, CommunityUpdateForm},
+    community::{Community, CommunityInsertForm, CommunityUpdateForm},
+    local_site::LocalSite,
   },
   traits::{ApubActor, Crud},
+  utils::naive_now,
 };
 use lemmy_db_views_actor::structs::CommunityFollowerView;
 use lemmy_utils::{error::LemmyError, spawn_try_task, utils::markdown::markdown_to_html};
@@ -130,7 +139,38 @@ impl Object for ApubCommunity {
   ) -> Result<ApubCommunity, LemmyError> {
     let instance_id = fetch_instance_actor_for_object(&group.id, context).await?;
 
-    let form = Group::into_insert_form(group.clone(), instance_id);
+    let local_site = LocalSite::read(&mut context.pool()).await.ok();
+    let slur_regex = &local_site_opt_to_slur_regex(&local_site);
+    let description = read_from_string_or_source_opt(&group.summary, &None, &group.source);
+    let description = process_markdown_opt(&description, slur_regex, context).await?;
+    let icon = proxy_image_link_opt_apub(group.icon.map(|i| i.url), context).await?;
+    let banner = proxy_image_link_opt_apub(group.image.map(|i| i.url), context).await?;
+
+    let form = CommunityInsertForm {
+      name: group.preferred_username.clone(),
+      title: group.name.unwrap_or(group.preferred_username.clone()),
+      description,
+      removed: None,
+      published: group.published,
+      updated: group.updated,
+      deleted: Some(false),
+      nsfw: Some(group.sensitive.unwrap_or(false)),
+      actor_id: Some(group.id.into()),
+      local: Some(false),
+      private_key: None,
+      hidden: None,
+      public_key: group.public_key.public_key_pem,
+      last_refreshed_at: Some(naive_now()),
+      icon,
+      banner,
+      followers_url: Some(group.followers.clone().into()),
+      inbox_url: Some(group.inbox.into()),
+      shared_inbox_url: group.endpoints.map(|e| e.shared_inbox.into()),
+      moderators_url: group.attributed_to.clone().map(Into::into),
+      posting_restricted_to_mods: group.posting_restricted_to_mods,
+      instance_id,
+      featured_url: group.featured.map(Into::into),
+    };
     let languages =
       LanguageTag::to_language_id_multiple(group.language, &mut context.pool()).await?;
 
@@ -212,7 +252,7 @@ impl ApubCommunity {
 pub(crate) mod tests {
   use super::*;
   use crate::{
-    objects::{instance::tests::parse_lemmy_instance, tests::init_context},
+    objects::instance::tests::parse_lemmy_instance,
     protocol::tests::file_to_json_object,
   };
   use activitypub_federation::fetch::collection_id::CollectionId;
@@ -241,7 +281,7 @@ pub(crate) mod tests {
   #[tokio::test]
   #[serial]
   async fn test_parse_lemmy_community() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
     let site = parse_lemmy_instance(&context).await?;
     let community = parse_lemmy_community(&context).await?;
 

crates/apub/src/objects/instance.rs

@@ -17,13 +17,17 @@ use activitypub_federation::{
   traits::{Actor, Object},
 };
 use chrono::{DateTime, Utc};
-use lemmy_api_common::{context::LemmyContext, utils::local_site_opt_to_slur_regex};
+use lemmy_api_common::{
+  context::LemmyContext,
+  utils::{local_site_opt_to_slur_regex, process_markdown_opt, proxy_image_link_opt_apub},
+};
 use lemmy_db_schema::{
   newtypes::InstanceId,
   source::{
     activity::ActorType,
     actor_language::SiteLanguage,
     instance::Instance as DbInstance,
+    local_site::LocalSite,
     site::{Site, SiteInsertForm},
   },
   traits::Crud,
@@ -126,18 +130,23 @@ impl Object for ApubSite {
   }
 
   #[tracing::instrument(skip_all)]
-  async fn from_json(apub: Self::Kind, data: &Data<Self::DataType>) -> Result<Self, LemmyError> {
+  async fn from_json(apub: Self::Kind, context: &Data<Self::DataType>) -> Result<Self, LemmyError> {
     let domain = apub.id.inner().domain().expect("group id has domain");
-    let instance = DbInstance::read_or_create(&mut data.pool(), domain.to_string()).await?;
+    let instance = DbInstance::read_or_create(&mut context.pool(), domain.to_string()).await?;
 
+    let local_site = LocalSite::read(&mut context.pool()).await.ok();
+    let slur_regex = &local_site_opt_to_slur_regex(&local_site);
     let sidebar = read_from_string_or_source_opt(&apub.content, &None, &apub.source);
+    let sidebar = process_markdown_opt(&sidebar, slur_regex, context).await?;
+    let icon = proxy_image_link_opt_apub(apub.icon.map(|i| i.url), context).await?;
+    let banner = proxy_image_link_opt_apub(apub.image.map(|i| i.url), context).await?;
 
     let site_form = SiteInsertForm {
       name: apub.name.clone(),
       sidebar,
       updated: apub.updated,
-      icon: apub.icon.clone().map(|i| i.url.into()),
+      icon,
-      banner: apub.image.clone().map(|i| i.url.into()),
+      banner,
       description: apub.summary,
       actor_id: Some(apub.id.clone().into()),
       last_refreshed_at: Some(naive_now()),
@@ -146,10 +155,11 @@ impl Object for ApubSite {
       private_key: None,
       instance_id: instance.id,
     };
-    let languages = LanguageTag::to_language_id_multiple(apub.language, &mut data.pool()).await?;
+    let languages =
+      LanguageTag::to_language_id_multiple(apub.language, &mut context.pool()).await?;
 
-    let site = Site::create(&mut data.pool(), &site_form).await?;
+    let site = Site::create(&mut context.pool(), &site_form).await?;
-    SiteLanguage::update(&mut data.pool(), languages, &site).await?;
+    SiteLanguage::update(&mut context.pool(), languages, &site).await?;
     Ok(site.into())
   }
 }
@@ -205,7 +215,7 @@ pub(in crate::objects) async fn fetch_instance_actor_for_object<T: Into<Url> + C
 #[cfg(test)]
 pub(crate) mod tests {
   use super::*;
-  use crate::{objects::tests::init_context, protocol::tests::file_to_json_object};
+  use crate::protocol::tests::file_to_json_object;
   use lemmy_db_schema::traits::Crud;
   use lemmy_utils::error::LemmyResult;
   use pretty_assertions::assert_eq;
@@ -223,7 +233,7 @@ pub(crate) mod tests {
   #[tokio::test]
   #[serial]
   async fn test_parse_lemmy_instance() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
     let site = parse_lemmy_instance(&context).await?;
 
     assert_eq!(site.name, "Enterprise");

crates/apub/src/objects/mod.rs

@@ -51,54 +51,3 @@ pub(crate) fn verify_is_remote_object(id: &Url, settings: &Settings) -> Result<(
     Ok(())
   }
 }
-
-#[cfg(test)]
-pub(crate) mod tests {
-  use activitypub_federation::config::{Data, FederationConfig};
-  use anyhow::anyhow;
-  use lemmy_api_common::{context::LemmyContext, request::client_builder};
-  use lemmy_db_schema::{source::secret::Secret, utils::build_db_pool_for_tests};
-  use lemmy_utils::{error::LemmyResult, rate_limit::RateLimitCell, settings::SETTINGS};
-  use reqwest::{Request, Response};
-  use reqwest_middleware::{ClientBuilder, Middleware, Next};
-  use task_local_extensions::Extensions;
-
-  struct BlockedMiddleware;
-
-  /// A reqwest middleware which blocks all requests
-  #[async_trait::async_trait]
-  impl Middleware for BlockedMiddleware {
-    async fn handle(
-      &self,
-      _req: Request,
-      _extensions: &mut Extensions,
-      _next: Next<'_>,
-    ) -> reqwest_middleware::Result<Response> {
-      Err(anyhow!("Network requests not allowed").into())
-    }
-  }
-
-  // TODO: would be nice if we didnt have to use a full context for tests.
-  pub(crate) async fn init_context() -> LemmyResult<Data<LemmyContext>> {
-    // call this to run migrations
-    let pool = build_db_pool_for_tests().await;
-
-    let client = client_builder(&SETTINGS).build()?;
-
-    let client = ClientBuilder::new(client).with(BlockedMiddleware).build();
-    let secret = Secret {
-      id: 0,
-      jwt_secret: String::new(),
-    };
-
-    let rate_limit_cell = RateLimitCell::with_test_config();
-
-    let context = LemmyContext::create(pool, client, secret, rate_limit_cell.clone());
-    let config = FederationConfig::builder()
-      .domain("example.com")
-      .app_data(context)
-      .build()
-      .await?;
-    Ok(config.to_request_data())
-  }
-}

crates/apub/src/objects/person.rs

@@ -20,11 +20,17 @@ use activitypub_federation::{
 use chrono::{DateTime, Utc};
 use lemmy_api_common::{
   context::LemmyContext,
-  utils::{generate_outbox_url, local_site_opt_to_slur_regex},
+  utils::{
+    generate_outbox_url,
+    local_site_opt_to_slur_regex,
+    process_markdown_opt,
+    proxy_image_link_opt_apub,
+  },
 };
 use lemmy_db_schema::{
   source::{
     activity::ActorType,
+    local_site::LocalSite,
     person::{Person as DbPerson, PersonInsertForm, PersonUpdateForm},
   },
   traits::{ApubActor, Crud},
@@ -144,7 +150,12 @@ impl Object for ApubPerson {
   ) -> Result<ApubPerson, LemmyError> {
     let instance_id = fetch_instance_actor_for_object(&person.id, context).await?;
 
+    let local_site = LocalSite::read(&mut context.pool()).await.ok();
+    let slur_regex = &local_site_opt_to_slur_regex(&local_site);
     let bio = read_from_string_or_source_opt(&person.summary, &None, &person.source);
+    let bio = process_markdown_opt(&bio, slur_regex, context).await?;
+    let avatar = proxy_image_link_opt_apub(person.icon.map(|i| i.url), context).await?;
+    let banner = proxy_image_link_opt_apub(person.image.map(|i| i.url), context).await?;
 
     // Some Mastodon users have `name: ""` (empty string), need to convert that to `None`
     // https://github.com/mastodon/mastodon/issues/25233
@@ -156,8 +167,8 @@ impl Object for ApubPerson {
       banned: None,
       ban_expires: None,
       deleted: Some(false),
-      avatar: person.icon.map(|i| i.url.into()),
+      avatar,
-      banner: person.image.map(|i| i.url.into()),
+      banner,
       published: person.published.map(Into::into),
       updated: person.updated.map(Into::into),
       actor_id: Some(person.id.into()),
@@ -210,10 +221,7 @@ impl GetActorType for ApubPerson {
 pub(crate) mod tests {
   use super::*;
   use crate::{
-    objects::{
+    objects::instance::{tests::parse_lemmy_instance, ApubSite},
-      instance::{tests::parse_lemmy_instance, ApubSite},
-      tests::init_context,
-    },
     protocol::{objects::instance::Instance, tests::file_to_json_object},
   };
   use activitypub_federation::fetch::object_id::ObjectId;
@@ -237,7 +245,7 @@ pub(crate) mod tests {
   #[tokio::test]
   #[serial]
   async fn test_parse_lemmy_person() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
     let (person, site) = parse_lemmy_person(&context).await?;
 
     assert_eq!(person.display_name, Some("Jean-Luc Picard".to_string()));
@@ -251,7 +259,7 @@ pub(crate) mod tests {
   #[tokio::test]
   #[serial]
   async fn test_parse_pleroma_person() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
 
     // create and parse a fake pleroma instance actor, to avoid network request during test
     let mut json: Instance = file_to_json_object("assets/lemmy/objects/instance.json")?;

crates/apub/src/objects/post.rs

@@ -24,8 +24,14 @@ use chrono::{DateTime, Utc};
 use html2text::{from_read_with_decorator, render::text_renderer::TrivialDecorator};
 use lemmy_api_common::{
   context::LemmyContext,
-  request::fetch_site_data,
+  request::fetch_link_metadata_opt,
-  utils::{is_mod_or_admin, local_site_opt_to_sensitive, local_site_opt_to_slur_regex},
+  utils::{
+    is_mod_or_admin,
+    local_site_opt_to_sensitive,
+    local_site_opt_to_slur_regex,
+    process_markdown_opt,
+    proxy_image_link_opt_apub,
+  },
 };
 use lemmy_db_schema::{
   self,
@@ -40,11 +46,7 @@ use lemmy_db_schema::{
 };
 use lemmy_utils::{
   error::LemmyError,
-  utils::{
+  utils::{markdown::markdown_to_html, slurs::check_slurs_opt, validation::check_url_scheme},
-    markdown::markdown_to_html,
-    slurs::{check_slurs_opt, remove_slurs},
-    validation::check_url_scheme,
-  },
 };
 use std::ops::Deref;
 use stringreader::StringReader;
@@ -111,6 +113,13 @@ impl Object for ApubPost {
     let community = Community::read(&mut context.pool(), community_id).await?;
     let language = LanguageTag::new_single(self.language_id, &mut context.pool()).await?;
 
+    let attachment = self
+      .url
+      .clone()
+      .map(|url| Attachment::new(url.into(), self.url_content_type.clone()))
+      .into_iter()
+      .collect();
+
     let page = Page {
       kind: PageType::Page,
       id: self.ap_id.clone().into(),
@@ -121,7 +130,7 @@ impl Object for ApubPost {
       content: self.body.as_ref().map(|b| markdown_to_html(b)),
       media_type: Some(MediaTypeMarkdownOrHtml::Html),
       source: self.body.clone().map(Source::new),
-      attachment: self.url.clone().map(Attachment::new).into_iter().collect(),
+      attachment,
       image: self.thumbnail_url.clone().map(ImageObject::new),
       comments_enabled: Some(!self.locked),
       sensitive: Some(self.nsfw),
@@ -210,33 +219,22 @@ impl Object for ApubPost {
       let local_site = LocalSite::read(&mut context.pool()).await.ok();
       let allow_sensitive = local_site_opt_to_sensitive(&local_site);
       let page_is_sensitive = page.sensitive.unwrap_or(false);
-      let include_image = allow_sensitive || !page_is_sensitive;
+      let allow_generate_thumbnail = allow_sensitive || !page_is_sensitive;
+      let mut thumbnail_url = page.image.map(|i| i.url);
+      let do_generate_thumbnail = thumbnail_url.is_none() && allow_generate_thumbnail;
 
-      // Only fetch metadata if the post has a url and was not seen previously. We dont want to
+      // Generate local thumbnail only if no thumbnail was federated and 'sensitive' attributes allow it.
-      // waste resources by fetching metadata for the same post multiple times.
+      let metadata = fetch_link_metadata_opt(url.as_ref(), do_generate_thumbnail, context).await;
-      // Additionally, only fetch image if content is not sensitive or is allowed on local site.
+      if let Some(thumbnail_url_) = metadata.thumbnail {
-      let (metadata_res, thumbnail) = match &url {
+        thumbnail_url = Some(thumbnail_url_.into());
-        Some(url) if old_post.is_err() => {
-          fetch_site_data(
-            context.client(),
-            context.settings(),
-            Some(url),
-            include_image,
-          )
-          .await
       }
-        _ => (None, None),
+      let url = proxy_image_link_opt_apub(url, context).await?;
-      };
+      let thumbnail_url = proxy_image_link_opt_apub(thumbnail_url, context).await?;
-      // If no image was included with metadata, use post image instead when available.
-      let thumbnail_url = thumbnail.or_else(|| page.image.map(|i| i.url.into()));
 
-      let (embed_title, embed_description, embed_video_url) = metadata_res
-        .map(|u| (u.title, u.description, u.embed_video_url))
-        .unwrap_or_default();
       let slur_regex = &local_site_opt_to_slur_regex(&local_site);
 
-      let body = read_from_string_or_source_opt(&page.content, &page.media_type, &page.source)
+      let body = read_from_string_or_source_opt(&page.content, &page.media_type, &page.source);
-        .map(|s| remove_slurs(&s, slur_regex));
+      let body = process_markdown_opt(&body, slur_regex, context).await?;
       let language_id =
         LanguageTag::to_language_id_single(page.language, &mut context.pool()).await?;
 
@@ -252,15 +250,16 @@ impl Object for ApubPost {
         updated: page.updated.map(Into::into),
         deleted: Some(false),
         nsfw: page.sensitive,
-        embed_title,
+        embed_title: metadata.opengraph_data.title,
-        embed_description,
+        embed_description: metadata.opengraph_data.description,
-        embed_video_url,
+        embed_video_url: metadata.opengraph_data.embed_video_url,
         thumbnail_url,
         ap_id: Some(page.id.clone().into()),
         local: Some(false),
         language_id,
         featured_community: None,
         featured_local: None,
+        url_content_type: metadata.content_type,
       }
     } else {
       // if is mod action, only update locked/stickied fields, nothing else
@@ -299,7 +298,6 @@ mod tests {
       instance::ApubSite,
       person::{tests::parse_lemmy_person, ApubPerson},
       post::ApubPost,
-      tests::init_context,
     },
     protocol::tests::file_to_json_object,
   };
@@ -311,7 +309,7 @@ mod tests {
   #[tokio::test]
   #[serial]
   async fn test_parse_lemmy_post() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
     let (person, site) = parse_lemmy_person(&context).await?;
     let community = parse_lemmy_community(&context).await?;
 
@@ -335,7 +333,7 @@ mod tests {
   #[tokio::test]
   #[serial]
   async fn test_convert_mastodon_post_title() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
     let (person, site) = parse_lemmy_person(&context).await?;
     let community = parse_lemmy_community(&context).await?;
 

crates/apub/src/objects/private_message.rs

@@ -12,9 +12,13 @@ use activitypub_federation::{
   traits::Object,
 };
 use chrono::{DateTime, Utc};
-use lemmy_api_common::{context::LemmyContext, utils::check_person_block};
+use lemmy_api_common::{
+  context::LemmyContext,
+  utils::{check_person_block, local_site_opt_to_slur_regex, process_markdown},
+};
 use lemmy_db_schema::{
   source::{
+    local_site::LocalSite,
     person::Person,
     private_message::{PrivateMessage, PrivateMessageInsertForm},
   },
@@ -121,7 +125,10 @@ impl Object for ApubPrivateMessage {
     let recipient = note.to[0].dereference(context).await?;
     check_person_block(creator.id, recipient.id, &mut context.pool()).await?;
 
+    let local_site = LocalSite::read(&mut context.pool()).await.ok();
+    let slur_regex = &local_site_opt_to_slur_regex(&local_site);
     let content = read_from_string_or_source(&note.content, &None, &note.source);
+    let content = process_markdown(&content, slur_regex, context).await?;
 
     let form = PrivateMessageInsertForm {
       creator_id: creator.id,
@@ -146,7 +153,6 @@ mod tests {
     objects::{
       instance::{tests::parse_lemmy_instance, ApubSite},
       person::ApubPerson,
-      tests::init_context,
     },
     protocol::tests::file_to_json_object,
   };
@@ -185,7 +191,7 @@ mod tests {
   #[tokio::test]
   #[serial]
   async fn test_parse_lemmy_pm() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
     let url = Url::parse("https://enterprise.lemmy.ml/private_message/1621")?;
     let data = prepare_comment_test(&url, &context).await?;
     let json: ChatMessage = file_to_json_object("assets/lemmy/objects/chat_message.json")?;
@@ -208,7 +214,7 @@ mod tests {
   #[tokio::test]
   #[serial]
   async fn test_parse_pleroma_pm() -> LemmyResult<()> {
-    let context = init_context().await?;
+    let context = LemmyContext::init_test_context().await;
     let url = Url::parse("https://enterprise.lemmy.ml/private_message/1621")?;
     let data = prepare_comment_test(&url, &context).await?;
     let pleroma_url = Url::parse("https://queer.hacktivis.me/objects/2")?;

crates/apub/src/protocol/objects/group.rs

@@ -25,11 +25,6 @@ use activitypub_federation::{
 };
 use chrono::{DateTime, Utc};
 use lemmy_api_common::{context::LemmyContext, utils::local_site_opt_to_slur_regex};
-use lemmy_db_schema::{
-  newtypes::InstanceId,
-  source::community::{CommunityInsertForm, CommunityUpdateForm},
-  utils::naive_now,
-};
 use lemmy_utils::{
   error::LemmyError,
   utils::slurs::{check_slurs, check_slurs_opt},
@@ -94,64 +89,4 @@ impl Group {
     check_slurs_opt(&description, slur_regex)?;
     Ok(())
   }
-
-  pub(crate) fn into_insert_form(self, instance_id: InstanceId) -> CommunityInsertForm {
-    let description = read_from_string_or_source_opt(&self.summary, &None, &self.source);
-
-    CommunityInsertForm {
-      name: self.preferred_username.clone(),
-      title: self.name.unwrap_or(self.preferred_username.clone()),
-      description,
-      removed: None,
-      published: self.published,
-      updated: self.updated,
-      deleted: Some(false),
-      nsfw: Some(self.sensitive.unwrap_or(false)),
-      actor_id: Some(self.id.into()),
-      local: Some(false),
-      private_key: None,
-      hidden: None,
-      public_key: self.public_key.public_key_pem,
-      last_refreshed_at: Some(naive_now()),
-      icon: self.icon.map(|i| i.url.into()),
-      banner: self.image.map(|i| i.url.into()),
-      followers_url: Some(self.followers.into()),
-      inbox_url: Some(self.inbox.into()),
-      shared_inbox_url: self.endpoints.map(|e| e.shared_inbox.into()),
-      moderators_url: self.attributed_to.map(Into::into),
-      posting_restricted_to_mods: self.posting_restricted_to_mods,
-      instance_id,
-      featured_url: self.featured.map(Into::into),
-    }
-  }
-
-  pub(crate) fn into_update_form(self) -> CommunityUpdateForm {
-    CommunityUpdateForm {
-      title: Some(self.name.unwrap_or(self.preferred_username)),
-      description: Some(read_from_string_or_source_opt(
-        &self.summary,
-        &None,
-        &self.source,
-      )),
-      removed: None,
-      published: self.published.map(Into::into),
-      updated: Some(self.updated.map(Into::into)),
-      deleted: None,
-      nsfw: Some(self.sensitive.unwrap_or(false)),
-      actor_id: Some(self.id.into()),
-      local: None,
-      private_key: None,
-      hidden: None,
-      public_key: Some(self.public_key.public_key_pem),
-      last_refreshed_at: Some(naive_now()),
-      icon: Some(self.icon.map(|i| i.url.into())),
-      banner: Some(self.image.map(|i| i.url.into())),
-      followers_url: Some(self.followers.into()),
-      inbox_url: Some(self.inbox.into()),
-      shared_inbox_url: Some(self.endpoints.map(|e| e.shared_inbox.into())),
-      moderators_url: self.attributed_to.map(Into::into),
-      posting_restricted_to_mods: self.posting_restricted_to_mods,
-      featured_url: self.featured.map(Into::into),
-    }
-  }
 }

crates/apub/src/protocol/objects/page.rs

@@ -20,7 +20,6 @@ use activitypub_federation::{
 use chrono::{DateTime, Utc};
 use itertools::Itertools;
 use lemmy_api_common::context::LemmyContext;
-use lemmy_db_schema::newtypes::DbUrl;
 use lemmy_utils::error::{LemmyError, LemmyErrorType};
 use serde::{de::Error, Deserialize, Deserializer, Serialize};
 use serde_with::skip_serializing_none;
@@ -72,24 +71,25 @@ pub struct Page {
 #[derive(Clone, Debug, Deserialize, Serialize)]
 #[serde(rename_all = "camelCase")]
 pub(crate) struct Link {
-  pub(crate) href: Url,
+  href: Url,
-  pub(crate) r#type: LinkType,
+  media_type: Option<String>,
+  r#type: LinkType,
 }
 
 #[derive(Clone, Debug, Deserialize, Serialize)]
 #[serde(rename_all = "camelCase")]
 pub(crate) struct Image {
   #[serde(rename = "type")]
-  pub(crate) kind: ImageType,
+  kind: ImageType,
-  pub(crate) url: Url,
+  url: Url,
 }
 
 #[derive(Clone, Debug, Deserialize, Serialize)]
 #[serde(rename_all = "camelCase")]
 pub(crate) struct Document {
   #[serde(rename = "type")]
-  pub(crate) kind: DocumentType,
+  kind: DocumentType,
-  pub(crate) url: Url,
+  url: Url,
 }
 
 #[derive(Clone, Debug, Deserialize, Serialize)]
@@ -167,13 +167,23 @@ impl Page {
 }
 
 impl Attachment {
-  pub(crate) fn new(url: DbUrl) -> Attachment {
+  /// Creates new attachment for a given link and mime type.
+  pub(crate) fn new(url: Url, media_type: Option<String>) -> Attachment {
+    let is_image = media_type.clone().unwrap_or_default().starts_with("image");
+    if is_image {
+      Attachment::Image(Image {
+        kind: Default::default(),
+        url,
+      })
+    } else {
       Attachment::Link(Link {
-      href: url.into(),
+        href: url,
+        media_type,
         r#type: Default::default(),
       })
     }
   }
+}
 
 // Used for community outbox, so that it can be compatible with Pleroma/Mastodon.
 #[async_trait::async_trait]

crates/db_schema/src/impls/image_upload.rs

@@ -1,35 +0,0 @@
-use crate::{
-  newtypes::LocalUserId,
-  schema::image_upload::dsl::{image_upload, local_user_id},
-  source::image_upload::{ImageUpload, ImageUploadForm},
-  utils::{get_conn, DbPool},
-};
-use diesel::{insert_into, result::Error, ExpressionMethods, QueryDsl, Table};
-use diesel_async::RunQueryDsl;
-
-impl ImageUpload {
-  pub async fn create(pool: &mut DbPool<'_>, form: &ImageUploadForm) -> Result<Self, Error> {
-    let conn = &mut get_conn(pool).await?;
-    insert_into(image_upload)
-      .values(form)
-      .get_result::<Self>(conn)
-      .await
-  }
-
-  pub async fn get_all_by_local_user_id(
-    pool: &mut DbPool<'_>,
-    user_id: &LocalUserId,
-  ) -> Result<Vec<Self>, Error> {
-    let conn = &mut get_conn(pool).await?;
-    image_upload
-      .filter(local_user_id.eq(user_id))
-      .select(image_upload::all_columns())
-      .load::<ImageUpload>(conn)
-      .await
-  }
-
-  pub async fn delete_by_alias(pool: &mut DbPool<'_>, alias: &str) -> Result<usize, Error> {
-    let conn = &mut get_conn(pool).await?;
-    diesel::delete(image_upload.find(alias)).execute(conn).await
-  }
-}

crates/db_schema/src/impls/images.rs

@@ -0,0 +1,78 @@
+use crate::{
+  newtypes::{DbUrl, LocalUserId},
+  schema::{
+    local_image::dsl::{local_image, local_user_id, pictrs_alias},
+    remote_image::dsl::{link, remote_image},
+  },
+  source::images::{LocalImage, LocalImageForm, RemoteImage, RemoteImageForm},
+  utils::{get_conn, DbPool},
+};
+use diesel::{
+  dsl::exists,
+  insert_into,
+  result::Error,
+  select,
+  ExpressionMethods,
+  NotFound,
+  QueryDsl,
+  Table,
+};
+use diesel_async::RunQueryDsl;
+use url::Url;
+
+impl LocalImage {
+  pub async fn create(pool: &mut DbPool<'_>, form: &LocalImageForm) -> Result<Self, Error> {
+    let conn = &mut get_conn(pool).await?;
+    insert_into(local_image)
+      .values(form)
+      .get_result::<Self>(conn)
+      .await
+  }
+
+  pub async fn get_all_by_local_user_id(
+    pool: &mut DbPool<'_>,
+    user_id: &LocalUserId,
+  ) -> Result<Vec<Self>, Error> {
+    let conn = &mut get_conn(pool).await?;
+    local_image
+      .filter(local_user_id.eq(user_id))
+      .select(local_image::all_columns())
+      .load::<LocalImage>(conn)
+      .await
+  }
+
+  pub async fn delete_by_alias(pool: &mut DbPool<'_>, alias: &str) -> Result<usize, Error> {
+    let conn = &mut get_conn(pool).await?;
+    diesel::delete(local_image.filter(pictrs_alias.eq(alias)))
+      .execute(conn)
+      .await
+  }
+}
+
+impl RemoteImage {
+  pub async fn create(pool: &mut DbPool<'_>, links: Vec<Url>) -> Result<usize, Error> {
+    let conn = &mut get_conn(pool).await?;
+    let forms = links
+      .into_iter()
+      .map(|url| RemoteImageForm { link: url.into() })
+      .collect::<Vec<_>>();
+    insert_into(remote_image)
+      .values(forms)
+      .on_conflict_do_nothing()
+      .execute(conn)
+      .await
+  }
+
+  pub async fn validate(pool: &mut DbPool<'_>, link_: DbUrl) -> Result<(), Error> {
+    let conn = &mut get_conn(pool).await?;
+
+    let exists = select(exists(remote_image.filter((link).eq(link_))))
+      .get_result::<bool>(conn)
+      .await?;
+    if exists {
+      Ok(())
+    } else {
+      Err(NotFound)
+    }
+  }
+}

crates/db_schema/src/impls/mod.rs

@@ -11,7 +11,7 @@ pub mod email_verification;
 pub mod federation_allowlist;
 pub mod federation_blocklist;
 pub mod federation_queue_state;
-pub mod image_upload;
+pub mod images;
 pub mod instance;
 pub mod instance_block;
 pub mod language;

crates/db_schema/src/impls/post.rs

@@ -434,6 +434,7 @@ mod tests {
       language_id: Default::default(),
       featured_community: false,
       featured_local: false,
+      url_content_type: None,
     };
 
     // Post Like

crates/db_schema/src/schema.rs

@@ -301,15 +301,6 @@ diesel::table! {
     }
 }
 
-diesel::table! {
-    image_upload (pictrs_alias) {
-        local_user_id -> Int4,
-        pictrs_alias -> Text,
-        pictrs_delete_token -> Text,
-        published -> Timestamptz,
-    }
-}
-
 diesel::table! {
     instance (id) {
         id -> Int4,
@@ -341,6 +332,15 @@ diesel::table! {
     }
 }
 
+diesel::table! {
+    local_image (pictrs_alias) {
+        local_user_id -> Int4,
+        pictrs_alias -> Text,
+        pictrs_delete_token -> Text,
+        published -> Timestamptz,
+    }
+}
+
 diesel::table! {
     use diesel::sql_types::*;
     use super::sql_types::ListingTypeEnum;
@@ -692,6 +692,7 @@ diesel::table! {
         language_id -> Int4,
         featured_community -> Bool,
         featured_local -> Bool,
+        url_content_type -> Nullable<Text>,
     }
 }
 
@@ -807,6 +808,14 @@ diesel::table! {
     }
 }
 
+diesel::table! {
+    remote_image (id) {
+        id -> Int4,
+        link -> Text,
+        published -> Timestamptz,
+    }
+}
+
 diesel::table! {
     secret (id) {
         id -> Int4,
@@ -922,9 +931,9 @@ diesel::joinable!(email_verification -> local_user (local_user_id));
 diesel::joinable!(federation_allowlist -> instance (instance_id));
 diesel::joinable!(federation_blocklist -> instance (instance_id));
 diesel::joinable!(federation_queue_state -> instance (instance_id));
-diesel::joinable!(image_upload -> local_user (local_user_id));
 diesel::joinable!(instance_block -> instance (instance_id));
 diesel::joinable!(instance_block -> person (person_id));
+diesel::joinable!(local_image -> local_user (local_user_id));
 diesel::joinable!(local_site -> site (site_id));
 diesel::joinable!(local_site_rate_limit -> local_site (local_site_id));
 diesel::joinable!(local_user -> person (person_id));
@@ -1002,10 +1011,10 @@ diesel::allow_tables_to_appear_in_same_query!(
     federation_allowlist,
     federation_blocklist,
     federation_queue_state,
-    image_upload,
     instance,
     instance_block,
     language,
+    local_image,
     local_site,
     local_site_rate_limit,
     local_user,
@@ -1040,6 +1049,7 @@ diesel::allow_tables_to_appear_in_same_query!(
     private_message_report,
     received_activity,
     registration_application,
+    remote_image,
     secret,
     sent_activity,
     site,

crates/db_schema/src/source/images.rs

@@ -0,0 +1,50 @@
+use crate::newtypes::{DbUrl, LocalUserId};
+#[cfg(feature = "full")]
+use crate::schema::{local_image, remote_image};
+use chrono::{DateTime, Utc};
+use serde_with::skip_serializing_none;
+use std::fmt::Debug;
+use typed_builder::TypedBuilder;
+
+#[skip_serializing_none]
+#[derive(PartialEq, Eq, Debug, Clone)]
+#[cfg_attr(feature = "full", derive(Queryable, Associations))]
+#[cfg_attr(feature = "full", diesel(table_name = local_image))]
+#[cfg_attr(
+  feature = "full",
+  diesel(belongs_to(crate::source::local_user::LocalUser))
+)]
+pub struct LocalImage {
+  pub local_user_id: LocalUserId,
+  pub pictrs_alias: String,
+  pub pictrs_delete_token: String,
+  pub published: DateTime<Utc>,
+}
+
+#[derive(Debug, Clone, TypedBuilder)]
+#[cfg_attr(feature = "full", derive(Insertable, AsChangeset))]
+#[cfg_attr(feature = "full", diesel(table_name = local_image))]
+pub struct LocalImageForm {
+  pub local_user_id: LocalUserId,
+  pub pictrs_alias: String,
+  pub pictrs_delete_token: String,
+}
+
+/// Stores all images which are hosted on remote domains. When attempting to proxy an image, it
+/// is checked against this table to avoid Lemmy being used as a general purpose proxy.
+#[skip_serializing_none]
+#[derive(PartialEq, Eq, Debug, Clone)]
+#[cfg_attr(feature = "full", derive(Queryable, Identifiable))]
+#[cfg_attr(feature = "full", diesel(table_name = remote_image))]
+pub struct RemoteImage {
+  pub id: i32,
+  pub link: DbUrl,
+  pub published: DateTime<Utc>,
+}
+
+#[derive(Debug, Clone, TypedBuilder)]
+#[cfg_attr(feature = "full", derive(Insertable, AsChangeset))]
+#[cfg_attr(feature = "full", diesel(table_name = remote_image))]
+pub struct RemoteImageForm {
+  pub link: DbUrl,
+}

crates/db_schema/src/source/mod.rs

@@ -16,7 +16,7 @@ pub mod email_verification;
 pub mod federation_allowlist;
 pub mod federation_blocklist;
 pub mod federation_queue_state;
-pub mod image_upload;
+pub mod images;
 pub mod instance;
 pub mod instance_block;
 pub mod language;

crates/db_schema/src/source/post.rs

@@ -55,6 +55,7 @@ pub struct Post {
   pub featured_community: bool,
   /// Whether the post is featured to its site.
   pub featured_local: bool,
+  pub url_content_type: Option<String>,
 }
 
 #[derive(Debug, Clone, TypedBuilder)]
@@ -85,6 +86,7 @@ pub struct PostInsertForm {
   pub language_id: Option<LanguageId>,
   pub featured_community: Option<bool>,
   pub featured_local: Option<bool>,
+  pub url_content_type: Option<String>,
 }
 
 #[derive(Debug, Clone, Default)]
@@ -109,6 +111,7 @@ pub struct PostUpdateForm {
   pub language_id: Option<LanguageId>,
   pub featured_community: Option<bool>,
   pub featured_local: Option<bool>,
+  pub url_content_type: Option<String>,
 }
 
 #[derive(PartialEq, Eq, Debug)]

crates/db_views/src/comment_view.rs

@@ -1015,6 +1015,7 @@ mod tests {
         language_id: Default::default(),
         featured_community: false,
         featured_local: false,
+        url_content_type: None,
       },
       community: Community {
         id: data.inserted_community.id,

crates/db_views/src/post_view.rs

@@ -1468,6 +1468,7 @@ mod tests {
         language_id: LanguageId(47),
         featured_community: false,
         featured_local: false,
+        url_content_type: None,
       },
       my_vote: None,
       unread_comments: 0,

crates/routes/Cargo.toml

@@ -33,4 +33,5 @@ url = { workspace = true }
 once_cell = { workspace = true }
 tracing = { workspace = true }
 tokio = { workspace = true }
+urlencoding = { workspace = true }
 rss = "2.0.7"

crates/routes/src/images.rs

@@ -6,6 +6,7 @@ use actix_web::{
     StatusCode,
   },
   web,
+  web::Query,
   Error,
   HttpRequest,
   HttpResponse,
@@ -13,15 +14,17 @@ use actix_web::{
 use futures::stream::{Stream, StreamExt};
 use lemmy_api_common::context::LemmyContext;
 use lemmy_db_schema::source::{
-  image_upload::{ImageUpload, ImageUploadForm},
+  images::{LocalImage, LocalImageForm, RemoteImage},
   local_site::LocalSite,
 };
 use lemmy_db_views::structs::LocalUserView;
-use lemmy_utils::{rate_limit::RateLimitCell, REQWEST_TIMEOUT};
+use lemmy_utils::{error::LemmyResult, rate_limit::RateLimitCell, REQWEST_TIMEOUT};
 use reqwest::Body;
 use reqwest_middleware::{ClientWithMiddleware, RequestBuilder};
 use serde::{Deserialize, Serialize};
 use std::time::Duration;
+use url::Url;
+use urlencoding::decode;
 
 pub fn config(
   cfg: &mut web::ServiceConfig,
@@ -87,13 +90,14 @@ async fn upload(
   body: web::Payload,
   // require login
   local_user_view: LocalUserView,
+  client: web::Data<ClientWithMiddleware>,
   context: web::Data<LemmyContext>,
 ) -> Result<HttpResponse, Error> {
   // TODO: check rate limit here
   let pictrs_config = context.settings().pictrs_config()?;
   let image_url = format!("{}image", pictrs_config.url);
 
-  let mut client_req = adapt_request(&req, context.client(), image_url);
+  let mut client_req = adapt_request(&req, &client, image_url);
 
   if let Some(addr) = req.head().peer_addr {
     client_req = client_req.header("X-Forwarded-For", addr.to_string())
@@ -109,12 +113,12 @@ async fn upload(
   let images = res.json::<Images>().await.map_err(error::ErrorBadRequest)?;
   if let Some(images) = &images.files {
     for uploaded_image in images {
-      let form = ImageUploadForm {
+      let form = LocalImageForm {
         local_user_id: local_user_view.local_user.id,
         pictrs_alias: uploaded_image.file.to_string(),
         pictrs_delete_token: uploaded_image.delete_token.to_string(),
       };
-      ImageUpload::create(&mut context.pool(), &form)
+      LocalImage::create(&mut context.pool(), &form)
         .await
         .map_err(error::ErrorBadRequest)?;
     }
@@ -158,15 +162,15 @@ async fn full_res(
     url
   };
 
-  image(url, req, client).await
+  image(url, req, &client).await
 }
 
 async fn image(
   url: String,
   req: HttpRequest,
-  client: web::Data<ClientWithMiddleware>,
+  client: &ClientWithMiddleware,
 ) -> Result<HttpResponse, Error> {
-  let mut client_req = adapt_request(&req, &client, url);
+  let mut client_req = adapt_request(&req, client, url);
 
   if let Some(addr) = req.head().peer_addr {
     client_req = client_req.header("X-Forwarded-For", addr.to_string());
@@ -212,13 +216,35 @@ async fn delete(
 
   let res = client_req.send().await.map_err(error::ErrorBadRequest)?;
 
-  ImageUpload::delete_by_alias(&mut context.pool(), &file)
+  LocalImage::delete_by_alias(&mut context.pool(), &file)
     .await
     .map_err(error::ErrorBadRequest)?;
 
   Ok(HttpResponse::build(res.status()).body(BodyStream::new(res.bytes_stream())))
 }
 
+#[derive(Deserialize)]
+pub struct ImageProxyParams {
+  url: String,
+}
+
+pub async fn image_proxy(
+  Query(params): Query<ImageProxyParams>,
+  context: web::Data<LemmyContext>,
+) -> LemmyResult<HttpResponse> {
+  let url = Url::parse(&decode(&params.url)?)?;
+
+  // Check that url corresponds to a federated image so that this can't be abused as a proxy
+  // for arbitrary purposes.
+  RemoteImage::validate(&mut context.pool(), url.clone().into()).await?;
+
+  let pictrs_config = context.settings().pictrs_config()?;
+  let url = format!("{}image/original?proxy={}", pictrs_config.url, &params.url);
+  let image_response = context.client().get(url).send().await?;
+
+  Ok(HttpResponse::Ok().streaming(image_response.bytes_stream()))
+}
+
 fn make_send<S>(mut stream: S) -> impl Stream<Item = S::Item> + Send + Unpin + 'static
 where
   S: Stream + Unpin + 'static,

crates/utils/Cargo.toml

@@ -39,8 +39,8 @@ http = { workspace = true }
 doku = { workspace = true, features = ["url-2"] }
 uuid = { workspace = true, features = ["serde", "v4"] }
 rosetta-i18n = { workspace = true }
-percent-encoding = { workspace = true }
 tokio = { workspace = true }
+urlencoding = { workspace = true }
 openssl = "0.10.63"
 html2text = "0.6.0"
 deser-hjson = "2.2.4"

crates/utils/src/settings/mod.rs

@@ -6,12 +6,13 @@ use crate::{
 use anyhow::{anyhow, Context};
 use deser_hjson::from_str;
 use once_cell::sync::Lazy;
-use percent_encoding::{utf8_percent_encode, NON_ALPHANUMERIC};
 use regex::Regex;
 use std::{env, fs, io::Error};
+use urlencoding::encode;
 
 pub mod structs;
 
+use crate::settings::structs::PictrsImageMode;
 use structs::DatabaseConnection;
 
 static DEFAULT_CONFIG_FILE: &str = "config/config.hjson";
@@ -53,11 +54,11 @@ impl Settings {
       DatabaseConnection::Parts(parts) => {
         format!(
           "postgres://{}:{}@{}:{}/{}",
-          utf8_percent_encode(&parts.user, NON_ALPHANUMERIC),
+          encode(&parts.user),
-          utf8_percent_encode(&parts.password, NON_ALPHANUMERIC),
+          encode(&parts.password),
           parts.host,
           parts.port,
-          utf8_percent_encode(&parts.database, NON_ALPHANUMERIC),
+          encode(&parts.database),
         )
       }
     }
@@ -112,3 +113,17 @@ impl Settings {
       .ok_or_else(|| anyhow!("images_disabled").into())
   }
 }
+
+impl PictrsConfig {
+  pub fn image_mode(&self) -> PictrsImageMode {
+    if let Some(cache_external_link_previews) = self.cache_external_link_previews {
+      if cache_external_link_previews {
+        PictrsImageMode::StoreLinkPreviews
+      } else {
+        PictrsImageMode::None
+      }
+    } else {
+      self.image_mode.clone()
+    }
+  }
+}

crates/utils/src/settings/structs.rs

@@ -12,7 +12,6 @@ pub struct Settings {
   /// settings related to the postgresql database
   #[default(Default::default())]
   pub database: DatabaseConfig,
-  /// Settings related to activitypub federation
   /// Pictrs image server configuration.
   #[default(Some(Default::default()))]
   pub(crate) pictrs: Option<PictrsConfig>,
@@ -79,22 +78,43 @@ pub struct PictrsConfig {
   #[default(None)]
   pub api_key: Option<String>,
 
-  /// By default the thumbnails for external links are stored in pict-rs. This ensures that they
+  /// Backwards compatibility with 0.18.1. False is equivalent to `image_mode: None`, true is
-  /// can be reliably retrieved and can be resized using pict-rs APIs. However it also increases
+  /// equivalent to `image_mode: StoreLinkPreviews`.
-  /// storage usage. In case this is disabled, the Opengraph image is directly returned as
-  /// thumbnail.
   ///
-  /// In some countries it is forbidden to copy preview images from newspaper articles and only
+  /// To be removed in 0.20
-  /// hotlinking is allowed. If that is the case for your instance, make sure that this setting is
+  pub(super) cache_external_link_previews: Option<bool>,
-  /// disabled.
-  #[default(true)]
-  pub cache_external_link_previews: bool,
 
-  /// Timeout for uploading images to pictrs (in seconds)
+  /// Specifies how to handle remote images, so that users don't have to connect directly to remote servers.
+  #[default(PictrsImageMode::StoreLinkPreviews)]
+  pub(super) image_mode: PictrsImageMode,
+
+  /// Timeout for uploading images to pictrs (in seconds)
   #[default(30)]
   pub upload_timeout: u64,
 }
 
+#[derive(Debug, Deserialize, Serialize, Clone, SmartDefault, Document, PartialEq)]
+#[serde(deny_unknown_fields)]
+pub enum PictrsImageMode {
+  /// Leave images unchanged, don't generate any local thumbnails for post urls. Instead the the
+  /// Opengraph image is directly returned as thumbnail
+  None,
+  /// Generate thumbnails for external post urls and store them persistently in pict-rs. This
+  /// ensures that they can be reliably retrieved and can be resized using pict-rs APIs. However
+  /// it also increases storage usage.
+  ///
+  /// This is the default behaviour, and also matches Lemmy 0.18.
+  #[default]
+  StoreLinkPreviews,
+  /// If enabled, all images from remote domains are rewritten to pass through `/api/v3/image_proxy`,
+  /// including embedded images in markdown. Images are stored temporarily in pict-rs for caching.
+  /// This improves privacy as users don't expose their IP to untrusted servers, and decreases load
+  /// on other servers. However it increases bandwidth use for the local server.
+  ///
+  /// Requires pict-rs 0.5
+  ProxyAllImages,
+}
+
 #[derive(Debug, Deserialize, Serialize, Clone, SmartDefault, Document)]
 #[serde(default)]
 pub struct DatabaseConfig {

crates/utils/src/utils/markdown.rs

@@ -1,113 +0,0 @@
-use markdown_it::MarkdownIt;
-use once_cell::sync::Lazy;
-
-mod spoiler_rule;
-
-static MARKDOWN_PARSER: Lazy<MarkdownIt> = Lazy::new(|| {
-  let mut parser = MarkdownIt::new();
-  markdown_it::plugins::cmark::add(&mut parser);
-  markdown_it::plugins::extra::add(&mut parser);
-  spoiler_rule::add(&mut parser);
-
-  parser
-});
-
-/// Replace special HTML characters in API parameters to prevent XSS attacks.
-///
-/// Taken from https://github.com/OWASP/CheatSheetSeries/blob/master/cheatsheets/Cross_Site_Scripting_Prevention_Cheat_Sheet.md#output-encoding-for-html-contexts
-///
-/// `>` is left in place because it is interpreted as markdown quote.
-pub fn sanitize_html(text: &str) -> String {
-  text
-    .replace('&', "&amp;")
-    .replace('<', "&lt;")
-    .replace('\"', "&quot;")
-    .replace('\'', "&#x27;")
-}
-
-/// Converts text from markdown to HTML, while escaping special characters.
-pub fn markdown_to_html(text: &str) -> String {
-  MARKDOWN_PARSER.parse(text).xrender()
-}
-
-#[cfg(test)]
-mod tests {
-  #![allow(clippy::unwrap_used)]
-  #![allow(clippy::indexing_slicing)]
-
-  use super::*;
-  use pretty_assertions::assert_eq;
-
-  #[test]
-  fn test_basic_markdown() {
-    let tests: Vec<_> = vec![
-      (
-        "headings",
-        "# h1\n## h2\n### h3\n#### h4\n##### h5\n###### h6",
-        "<h1>h1</h1>\n<h2>h2</h2>\n<h3>h3</h3>\n<h4>h4</h4>\n<h5>h5</h5>\n<h6>h6</h6>\n"
-      ),
-      (
-        "line breaks",
-        "First\rSecond",
-        "<p>First\nSecond</p>\n"),
-      (
-        "emphasis",
-        "__bold__ **bold** *italic* ***bold+italic***",
-        "<p><strong>bold</strong> <strong>bold</strong> <em>italic</em> <em><strong>bold+italic</strong></em></p>\n"
-      ),
-      (
-        "blockquotes",
-        "> #### Hello\n > \n > - Hola\n > - 안영 \n>> Goodbye\n",
-        "<blockquote>\n<h4>Hello</h4>\n<ul>\n<li>Hola</li>\n<li>안영</li>\n</ul>\n<blockquote>\n<p>Goodbye</p>\n</blockquote>\n</blockquote>\n"
-      ),
-      (
-        "lists (ordered, unordered)",
-        "1. pen\n2. apple\n3. apple pen\n- pen\n- pineapple\n- pineapple pen",
-        "<ol>\n<li>pen</li>\n<li>apple</li>\n<li>apple pen</li>\n</ol>\n<ul>\n<li>pen</li>\n<li>pineapple</li>\n<li>pineapple pen</li>\n</ul>\n"
-      ),
-      (
-        "code and code blocks",
-        "this is my amazing `code snippet` and my amazing ```code block```",
-        "<p>this is my amazing <code>code snippet</code> and my amazing <code>code block</code></p>\n"
-      ),
-      (
-        "links",
-        "[Lemmy](https://join-lemmy.org/ \"Join Lemmy!\")",
-        "<p><a href=\"https://join-lemmy.org/\" title=\"Join Lemmy!\">Lemmy</a></p>\n"
-      ),
-      (
-        "images",
-        "![My linked image](https://image.com \"image alt text\")",
-        "<p><img src=\"https://image.com\" alt=\"My linked image\" title=\"image alt text\" /></p>\n"
-      ),
-      // Ensure any custom plugins are added to 'MARKDOWN_PARSER' implementation.
-      (
-        "basic spoiler",
-        "::: spoiler click to see more\nhow spicy!\n:::\n",
-        "<details><summary>click to see more</summary><p>how spicy!\n</p></details>\n"
-      ),
-      (
-          "escape html special chars",
-          "<script>alert('xss');</script> hello &\"",
-          "<p>&lt;script&gt;alert(‘xss’);&lt;/script&gt; hello &amp;&quot;</p>\n"
-          )
-    ];
-
-    tests.iter().for_each(|&(msg, input, expected)| {
-      let result = markdown_to_html(input);
-
-      assert_eq!(
-        result, expected,
-        "Testing {}, with original input '{}'",
-        msg, input
-      );
-    });
-  }
-
-  #[test]
-  fn test_sanitize_html() {
-    let sanitized = sanitize_html("<script>alert('xss');</script> hello &\"'");
-    let expected = "&lt;script>alert(&#x27;xss&#x27;);&lt;/script> hello &amp;&quot;&#x27;";
-    assert_eq!(expected, sanitized)
-  }
-}

crates/utils/src/utils/markdown/link_rule.rs

@@ -0,0 +1,38 @@
+use markdown_it::{generics::inline::full_link, MarkdownIt, Node, NodeValue, Renderer};
+
+/// Renders markdown links. Copied directly from markdown-it source, unlike original code it also
+/// sets `rel=nofollow` attribute.
+///
+/// TODO: We can set nofollow only if post was not made by mod/admin, but then we have to construct
+///       new parser for every invocation which might have performance implications.
+/// https://github.com/markdown-it-rust/markdown-it/blob/master/src/plugins/cmark/inline/link.rs
+#[derive(Debug)]
+pub struct Link {
+  pub url: String,
+  pub title: Option<String>,
+}
+
+impl NodeValue for Link {
+  fn render(&self, node: &Node, fmt: &mut dyn Renderer) {
+    let mut attrs = node.attrs.clone();
+    attrs.push(("href", self.url.clone()));
+    attrs.push(("rel", "nofollow".to_string()));
+
+    if let Some(title) = &self.title {
+      attrs.push(("title", title.clone()));
+    }
+
+    fmt.open("a", &attrs);
+    fmt.contents(&node.children);
+    fmt.close("a");
+  }
+}
+
+pub fn add(md: &mut MarkdownIt) {
+  full_link::add::<false>(md, |href, title| {
+    Node::new(Link {
+      url: href.unwrap_or_default(),
+      title,
+    })
+  });
+}

crates/utils/src/utils/markdown/mod.rs

@@ -0,0 +1,246 @@
+use crate::settings::SETTINGS;
+use markdown_it::{plugins::cmark::inline::image::Image, MarkdownIt};
+use once_cell::sync::Lazy;
+use url::Url;
+use urlencoding::encode;
+
+mod link_rule;
+mod spoiler_rule;
+
+static MARKDOWN_PARSER: Lazy<MarkdownIt> = Lazy::new(|| {
+  let mut parser = MarkdownIt::new();
+  markdown_it::plugins::cmark::add(&mut parser);
+  markdown_it::plugins::extra::add(&mut parser);
+  spoiler_rule::add(&mut parser);
+  link_rule::add(&mut parser);
+
+  parser
+});
+
+/// Replace special HTML characters in API parameters to prevent XSS attacks.
+///
+/// Taken from https://github.com/OWASP/CheatSheetSeries/blob/master/cheatsheets/Cross_Site_Scripting_Prevention_Cheat_Sheet.md#output-encoding-for-html-contexts
+///
+/// `>` is left in place because it is interpreted as markdown quote.
+pub fn sanitize_html(text: &str) -> String {
+  text
+    .replace('&', "&amp;")
+    .replace('<', "&lt;")
+    .replace('\"', "&quot;")
+    .replace('\'', "&#x27;")
+}
+
+pub fn markdown_to_html(text: &str) -> String {
+  MARKDOWN_PARSER.parse(text).xrender()
+}
+
+/// Rewrites all links to remote domains in markdown, so they go through `/api/v3/image_proxy`.
+pub fn markdown_rewrite_image_links(mut src: String) -> (String, Vec<Url>) {
+  let ast = MARKDOWN_PARSER.parse(&src);
+  let mut links_offsets = vec![];
+
+  // Walk the syntax tree to find positions of image links
+  ast.walk(|node, _depth| {
+    if let Some(image) = node.cast::<Image>() {
+      // srcmap is always present for image
+      // https://github.com/markdown-it-rust/markdown-it/issues/36#issuecomment-1777844387
+      let node_offsets = node.srcmap.expect("srcmap is none").get_byte_offsets();
+      // necessary for custom emojis which look like `![name](url "title")`
+      let start_offset = node_offsets.1
+        - image.url.len()
+        - 1
+        - image
+          .title
+          .as_ref()
+          .map(|t| t.len() + 3)
+          .unwrap_or_default();
+      let end_offset = node_offsets.1 - 1;
+
+      links_offsets.push((start_offset, end_offset));
+    }
+  });
+
+  let mut links = vec![];
+  // Go through the collected links in reverse order
+  while let Some((start, end)) = links_offsets.pop() {
+    let content = src.get(start..end).unwrap_or_default();
+    // necessary for custom emojis which look like `![name](url "title")`
+    let (url, extra) = if content.contains(' ') {
+      let split = content.split_once(' ').expect("split is valid");
+      (split.0, Some(split.1))
+    } else {
+      (content, None)
+    };
+    match Url::parse(url) {
+      Ok(parsed) => {
+        links.push(parsed.clone());
+        // If link points to remote domain, replace with proxied link
+        if parsed.domain() != Some(&SETTINGS.hostname) {
+          let mut proxied = format!(
+            "{}/api/v3/image_proxy?url={}",
+            SETTINGS.get_protocol_and_hostname(),
+            encode(url),
+          );
+          // restore custom emoji format
+          if let Some(extra) = extra {
+            proxied = format!("{proxied} {extra}");
+          }
+          src.replace_range(start..end, &proxied);
+        }
+      }
+      Err(_) => {
+        // If its not a valid url, replace with empty text
+        src.replace_range(start..end, "");
+      }
+    }
+  }
+
+  (src, links)
+}
+
+#[cfg(test)]
+mod tests {
+  #![allow(clippy::unwrap_used)]
+  #![allow(clippy::indexing_slicing)]
+
+  use super::*;
+  use pretty_assertions::assert_eq;
+
+  #[test]
+  fn test_basic_markdown() {
+    let tests: Vec<_> = vec![
+            (
+                "headings",
+                "# h1\n## h2\n### h3\n#### h4\n##### h5\n###### h6",
+                "<h1>h1</h1>\n<h2>h2</h2>\n<h3>h3</h3>\n<h4>h4</h4>\n<h5>h5</h5>\n<h6>h6</h6>\n"
+            ),
+            (
+                "line breaks",
+                "First\rSecond",
+                "<p>First\nSecond</p>\n"),
+            (
+                "emphasis",
+                "__bold__ **bold** *italic* ***bold+italic***",
+                "<p><strong>bold</strong> <strong>bold</strong> <em>italic</em> <em><strong>bold+italic</strong></em></p>\n"
+            ),
+            (
+                "blockquotes",
+                "> #### Hello\n > \n > - Hola\n > - 안영 \n>> Goodbye\n",
+                "<blockquote>\n<h4>Hello</h4>\n<ul>\n<li>Hola</li>\n<li>안영</li>\n</ul>\n<blockquote>\n<p>Goodbye</p>\n</blockquote>\n</blockquote>\n"
+            ),
+            (
+                "lists (ordered, unordered)",
+                "1. pen\n2. apple\n3. apple pen\n- pen\n- pineapple\n- pineapple pen",
+                "<ol>\n<li>pen</li>\n<li>apple</li>\n<li>apple pen</li>\n</ol>\n<ul>\n<li>pen</li>\n<li>pineapple</li>\n<li>pineapple pen</li>\n</ul>\n"
+            ),
+            (
+                "code and code blocks",
+                "this is my amazing `code snippet` and my amazing ```code block```",
+                "<p>this is my amazing <code>code snippet</code> and my amazing <code>code block</code></p>\n"
+            ),
+            // Links with added nofollow attribute
+            (
+                "links",
+                "[Lemmy](https://join-lemmy.org/ \"Join Lemmy!\")",
+                "<p><a href=\"https://join-lemmy.org/\" rel=\"nofollow\" title=\"Join Lemmy!\">Lemmy</a></p>\n"
+            ),
+            // Remote images with proxy
+            (
+                "images",
+                "![My linked image](https://example.com/image.png \"image alt text\")",
+                "<p><img src=\"https://example.com/image.png\" alt=\"My linked image\" title=\"image alt text\" /></p>\n"
+            ),
+            // Local images without proxy
+            (
+                "images",
+                "![My linked image](https://lemmy-alpha/image.png \"image alt text\")",
+                "<p><img src=\"https://lemmy-alpha/image.png\" alt=\"My linked image\" title=\"image alt text\" /></p>\n"
+            ),
+            // Ensure spoiler plugin is added
+            (
+                "basic spoiler",
+                "::: spoiler click to see more\nhow spicy!\n:::\n",
+                "<details><summary>click to see more</summary><p>how spicy!\n</p></details>\n"
+            ),
+            (
+                "escape html special chars",
+                "<script>alert('xss');</script> hello &\"",
+                "<p>&lt;script&gt;alert(‘xss’);&lt;/script&gt; hello &amp;&quot;</p>\n"
+            )
+        ];
+
+    tests.iter().for_each(|&(msg, input, expected)| {
+      let result = markdown_to_html(input);
+
+      assert_eq!(
+        result, expected,
+        "Testing {}, with original input '{}'",
+        msg, input
+      );
+    });
+  }
+
+  #[test]
+  fn test_markdown_proxy_images() {
+    let tests: Vec<_> =
+      vec![
+          (
+            "remote image proxied",
+            "![link](http://example.com/image.jpg)",
+            "![link](https://lemmy-alpha/api/v3/image_proxy?url=http%3A%2F%2Fexample.com%2Fimage.jpg)",
+          ),
+          (
+            "local image unproxied",
+            "![link](http://lemmy-alpha/image.jpg)",
+            "![link](http://lemmy-alpha/image.jpg)",
+          ),
+          (
+            "multiple image links",
+            "![link](http://example.com/image1.jpg) ![link](http://example.com/image2.jpg)",
+            "![link](https://lemmy-alpha/api/v3/image_proxy?url=http%3A%2F%2Fexample.com%2Fimage1.jpg) ![link](https://lemmy-alpha/api/v3/image_proxy?url=http%3A%2F%2Fexample.com%2Fimage2.jpg)",
+          ),
+          (
+            "empty link handled",
+            "![image]()",
+            "![image]()"
+          ),
+          (
+            "empty label handled",
+            "![](http://example.com/image.jpg)",
+            "![](https://lemmy-alpha/api/v3/image_proxy?url=http%3A%2F%2Fexample.com%2Fimage.jpg)"
+          ),
+         (
+            "invalid image link removed",
+            "![image](http-not-a-link)",
+            "![image]()"
+         ),
+         (
+            "label with nested markdown handled",
+            "![a *b* c](http://example.com/image.jpg)",
+            "![a *b* c](https://lemmy-alpha/api/v3/image_proxy?url=http%3A%2F%2Fexample.com%2Fimage.jpg)"
+         ),
+          (
+              "custom emoji support",
+              r#"![party-blob](https://www.hexbear.net/pictrs/image/83405746-0620-4728-9358-5f51b040ffee.gif "emoji party-blob")"#,
+              r#"![party-blob](https://lemmy-alpha/api/v3/image_proxy?url=https%3A%2F%2Fwww.hexbear.net%2Fpictrs%2Fimage%2F83405746-0620-4728-9358-5f51b040ffee.gif "emoji party-blob")"#
+              )
+      ];
+
+    tests.iter().for_each(|&(msg, input, expected)| {
+      let result = markdown_rewrite_image_links(input.to_string());
+
+      assert_eq!(
+        result.0, expected,
+        "Testing {}, with original input '{}'",
+        msg, input
+      );
+    });
+  }
+
+  #[test]
+  fn test_sanitize_html() {
+    let sanitized = sanitize_html("<script>alert('xss');</script> hello &\"'");
+    let expected = "&lt;script>alert(&#x27;xss&#x27;);&lt;/script> hello &amp;&quot;&#x27;";
+    assert_eq!(expected, sanitized)
+  }
+}

docker/federation/lemmy_epsilon.hjson

@@ -10,4 +10,8 @@
   database: {
     host: postgres_epsilon
   }
+  pictrs: {
+    api_key: "my-pictrs-key"
+    image_mode: ProxyAllImages
+  }
 }

docker/federation/lemmy_gamma.hjson

@@ -10,4 +10,8 @@
   database: {
     host: postgres_gamma
   }
+  pictrs: {
+    api_key: "my-pictrs-key"
+    image_mode: ProxyAllImages
+  }
 }

docker/lemmy.hjson

@@ -21,6 +21,7 @@
   pictrs: {
     url: "http://pictrs:8080/"
     # api_key: "API_KEY"
+    image_proxy: true
     cache_external_link_previews: true
   }
 

migrations/2023-10-24-131607_proxy_links/down.sql

@@ -0,0 +1,4 @@
+DROP TABLE remote_image;
+
+ALTER TABLE local_image RENAME TO image_upload;
+

migrations/2023-10-24-131607_proxy_links/up.sql

@@ -0,0 +1,8 @@
+CREATE TABLE remote_image (
+    id serial PRIMARY KEY,
+    link text NOT NULL UNIQUE,
+    published timestamptz DEFAULT now() NOT NULL
+);
+
+ALTER TABLE image_upload RENAME TO local_image;
+

migrations/2023-10-27-142514_post_url_content_type/down.sql

@@ -0,0 +1,3 @@
+ALTER TABLE post
+    DROP COLUMN url_content_type;
+

migrations/2023-10-27-142514_post_url_content_type/up.sql

@@ -0,0 +1,3 @@
+ALTER TABLE post
+    ADD COLUMN url_content_type text;
+

src/api_routes_http.rs

@@ -130,11 +130,13 @@ use lemmy_apub::api::{
   search::search,
   user_settings_backup::{export_settings, import_settings},
 };
+use lemmy_routes::images::image_proxy;
 use lemmy_utils::rate_limit::RateLimitCell;
 
 pub fn config(cfg: &mut web::ServiceConfig, rate_limit: &RateLimitCell) {
   cfg.service(
     web::scope("/api/v3")
+      .route("/image_proxy", web::get().to(image_proxy))
       // Site
       .service(
         web::scope("/site")

src/lib.rs

@@ -53,7 +53,7 @@ use lemmy_utils::{
 };
 use prometheus::default_registry;
 use prometheus_metrics::serve_prometheus;
-use reqwest_middleware::{ClientBuilder, ClientWithMiddleware};
+use reqwest_middleware::ClientBuilder;
 use reqwest_tracing::TracingMiddleware;
 use serde_json::json;
 use std::{env, ops::Deref};
@@ -198,15 +198,10 @@ pub async fn start_lemmy_server(args: CmdArgs) -> Result<(), LemmyError> {
       startup_server_handle.stop(true).await;
     }
 
-    // Pictrs cannot use proxy
-    let pictrs_client = ClientBuilder::new(client_builder(&SETTINGS).no_proxy().build()?)
-      .with(TracingMiddleware::default())
-      .build();
     Some(create_http_server(
       federation_config.clone(),
       SETTINGS.clone(),
       federation_enabled,
-      pictrs_client,
     )?)
   } else {
     None
@@ -272,7 +267,6 @@ fn create_http_server(
   federation_config: FederationConfig<LemmyContext>,
   settings: Settings,
   federation_enabled: bool,
-  pictrs_client: ClientWithMiddleware,
 ) -> Result<ServerHandle, LemmyError> {
   // this must come before the HttpServer creation
   // creates a middleware that populates http metrics for each path, method, and status code
@@ -284,6 +278,11 @@ fn create_http_server(
   let context: LemmyContext = federation_config.deref().clone();
   let rate_limit_cell = federation_config.rate_limit_cell().clone();
 
+  // Pictrs cannot use proxy
+  let pictrs_client = ClientBuilder::new(client_builder(&SETTINGS).no_proxy().build()?)
+    .with(TracingMiddleware::default())
+    .build();
+
   // Create Http server
   let bind = (settings.bind, settings.port);
   let server = HttpServer::new(move || {