This commit is contained in:
Matthew Hodgson 2016-04-03 12:56:29 +01:00
parent eab4d462f8
commit 8b98a7e8c3
4 changed files with 85 additions and 60 deletions

View File

@ -15,7 +15,9 @@
from OpenSSL import SSL
from OpenSSL.SSL import VERIFY_NONE
from synapse.api.errors import CodeMessageException
from synapse.api.errors import (
CodeMessageException, SynapseError, Codes,
)
from synapse.util.logcontext import preserve_context_over_fn
import synapse.metrics
@ -268,7 +270,7 @@ class SimpleHttpClient(object):
if 'Content-Length' in headers and headers['Content-Length'] > max_size:
logger.warn("Requested URL is too large > %r bytes" % (self.max_size,))
# XXX: do we want to explicitly drop the connection here somehow? if so, how?
raise # what should we be raising here?
raise # what should we be raising here?
if response.code > 299:
logger.warn("Got %d when downloading %s" % (response.code, url))
@ -331,6 +333,7 @@ def _readBodyToFile(response, stream, max_size):
response.deliverBody(_ReadBodyToFileProtocol(stream, d, max_size))
return d
class CaptchaServerHttpClient(SimpleHttpClient):
"""
Separate HTTP client for talking to google's captcha servers
@ -360,6 +363,7 @@ class CaptchaServerHttpClient(SimpleHttpClient):
# twisted dislikes google's response, no content length.
defer.returnValue(e.response)
class SpiderHttpClient(SimpleHttpClient):
"""
Separate HTTP client for spidering arbitrary URLs.
@ -376,8 +380,10 @@ class SpiderHttpClient(SimpleHttpClient):
connectTimeout=15,
contextFactory=hs.get_http_client_context_factory()
)), [('gzip', GzipDecoder)])
# Look like Chrome for now
#self.user_agent = ("Mozilla/5.0 (%s) (KHTML, like Gecko) Chrome Safari" % hs.version_string)
# We could look like Chrome:
# self.user_agent = ("Mozilla/5.0 (%s) (KHTML, like Gecko)
# Chrome Safari" % hs.version_string)
def encode_urlencode_args(args):
return {k: encode_urlencode_arg(v) for k, v in args.items()}

View File

@ -80,4 +80,3 @@ class MediaRepositoryResource(Resource):
self.putChild("thumbnail", ThumbnailResource(hs, filepaths))
self.putChild("identicon", IdenticonResource())
self.putChild("preview_url", PreviewUrlResource(hs, filepaths))

View File

@ -13,25 +13,31 @@
# limitations under the License.
from .base_resource import BaseMediaResource
from synapse.api.errors import Codes
from twisted.web.resource import Resource
from twisted.web.server import NOT_DONE_YET
from twisted.internet import defer
from lxml import html
from urlparse import urlparse, urlunparse
from synapse.api.errors import Codes
from synapse.util.stringutils import random_string
from synapse.util.caches.expiringcache import ExpiringCache
from synapse.http.client import SpiderHttpClient
from synapse.http.server import request_handler, respond_with_json, respond_with_json_bytes
from synapse.http.server import (
request_handler, respond_with_json, respond_with_json_bytes
)
from synapse.util.async import ObservableDeferred
from synapse.util.stringutils import is_ascii
import os
import re
import cgi
import ujson as json
import logging
logger = logging.getLogger(__name__)
class PreviewUrlResource(BaseMediaResource):
isLeaf = True
@ -41,9 +47,10 @@ class PreviewUrlResource(BaseMediaResource):
# simple memory cache mapping urls to OG metadata
self.cache = ExpiringCache(
cache_name = "url_previews",
clock = self.clock,
expiry_ms = 60*60*1000, # don't spider URLs more often than once an hour
cache_name="url_previews",
clock=self.clock,
# don't spider URLs more often than once an hour
expiry_ms=60 * 60 * 1000,
)
self.cache.start()
@ -56,12 +63,15 @@ class PreviewUrlResource(BaseMediaResource):
@request_handler
@defer.inlineCallbacks
def _async_render_GET(self, request):
try:
# XXX: if get_user_by_req fails, what should we do in an async render?
requester = yield self.auth.get_user_by_req(request)
url = request.args.get("url")[0]
ts = int(request.args.get("ts")[0]) if "ts" in request.args else self.clock.time_msec()
if "ts" in request.args:
ts = int(request.args.get("ts")[0])
else:
ts = self.clock.time_msec()
# first check the memory cache - good to handle all the clients on this
# HS thundering away to preview the same URL at the same time.
@ -98,7 +108,7 @@ class PreviewUrlResource(BaseMediaResource):
@download.addBoth
def callback(media_info):
del self.downloads[key]
del self.downloads[url]
return media_info
media_info = yield download.observe()
@ -111,13 +121,15 @@ class PreviewUrlResource(BaseMediaResource):
if self._is_media(media_info['media_type']):
dims = yield self._generate_local_thumbnails(
media_info['filesystem_id'], media_info
)
media_info['filesystem_id'], media_info
)
og = {
"og:description" : media_info['download_name'],
"og:image" : "mxc://%s/%s" % (self.server_name, media_info['filesystem_id']),
"og:image:type" : media_info['media_type'],
"og:description": media_info['download_name'],
"og:image": "mxc://%s/%s" % (
self.server_name, media_info['filesystem_id']
),
"og:image:type": media_info['media_type'],
}
if dims:
@ -138,14 +150,14 @@ class PreviewUrlResource(BaseMediaResource):
file = open(media_info['filename'])
body = file.read()
file.close()
tree = html.fromstring(body.decode('utf-8','ignore'))
tree = html.fromstring(body.decode('utf-8', 'ignore'))
og = yield self._calc_og(tree, media_info, requester)
else:
logger.warn("Failed to find any OG data in %s", url)
og = {}
logger.debug("Calculated OG for %s as %s" % (url, og));
logger.debug("Calculated OG for %s as %s" % (url, og))
# store OG in ephemeral in-memory cache
self.cache[url] = og
@ -181,28 +193,20 @@ class PreviewUrlResource(BaseMediaResource):
# suck our tree into lxml and define our OG response.
# if we see any image URLs in the OG response, then spider them
# (although the client could choose to do this by asking for previews of those URLs to avoid DoSing the server)
# "og:type" : "article"
# "og:url" : "https://twitter.com/matrixdotorg/status/684074366691356672"
# "og:title" : "Matrix on Twitter"
# "og:image" : "https://pbs.twimg.com/profile_images/500400952029888512/yI0qtFi7_400x400.png"
# "og:description" : "Synapse 0.12 is out! Lots of polishing, performance & bugfixes: /sync API, /r0 prefix, fulltext search, 3PID invites https://t.co/5alhXLLEGP"
# "og:site_name" : "Twitter"
# or:
# (although the client could choose to do this by asking for previews of those
# URLs to avoid DoSing the server)
# "og:type" : "video",
# "og:url" : "https://www.youtube.com/watch?v=LXDBoHyjmtw",
# "og:site_name" : "YouTube",
# "og:video:type" : "application/x-shockwave-flash",
# "og:description" : " ",
# "og:description" : "Fun stuff happening here",
# "og:title" : "RemoteJam - Matrix team hack for Disrupt Europe Hackathon",
# "og:image" : "https://i.ytimg.com/vi/LXDBoHyjmtw/maxresdefault.jpg",
# "og:video:url" : "http://www.youtube.com/v/LXDBoHyjmtw?version=3&autohide=1",
# "og:video:width" : "1280"
# "og:video:height" : "720",
# "og:video:secure_url": "https://www.youtube.com/v/LXDBoHyjmtw?version=3&autohide=1",
# "og:video:secure_url": "https://www.youtube.com/v/LXDBoHyjmtw?version=3",
og = {}
for tag in tree.xpath("//*/meta[starts-with(@property, 'og:')]"):
@ -210,64 +214,76 @@ class PreviewUrlResource(BaseMediaResource):
# TODO: grab article: meta tags too, e.g.:
# <meta property="article:publisher" content="https://www.facebook.com/thethudonline" />
# <meta property="article:author" content="https://www.facebook.com/thethudonline" />
# <meta property="article:tag" content="baby" />
# <meta property="article:section" content="Breaking News" />
# <meta property="article:published_time" content="2016-03-31T19:58:24+00:00" />
# <meta property="article:modified_time" content="2016-04-01T18:31:53+00:00" />
# "article:publisher" : "https://www.facebook.com/thethudonline" />
# "article:author" content="https://www.facebook.com/thethudonline" />
# "article:tag" content="baby" />
# "article:section" content="Breaking News" />
# "article:published_time" content="2016-03-31T19:58:24+00:00" />
# "article:modified_time" content="2016-04-01T18:31:53+00:00" />
if 'og:title' not in og:
# do some basic spidering of the HTML
title = tree.xpath("(//title)[1] | (//h1)[1] | (//h2)[1] | (//h3)[1]")
og['og:title'] = title[0].text.strip() if title else None
if 'og:image' not in og:
# TODO: extract a favicon failing all else
meta_image = tree.xpath("//*/meta[translate(@itemprop, 'IMAGE', 'image')='image']/@content");
meta_image = tree.xpath(
"//*/meta[translate(@itemprop, 'IMAGE', 'image')='image']/@content"
)
if meta_image:
og['og:image'] = self._rebase_url(meta_image[0], media_info['uri'])
else:
# TODO: consider inlined CSS styles as well as width & height attribs
images = tree.xpath("//img[@src][number(@width)>10][number(@height)>10]")
images = sorted(images, key=lambda i: (-1 * int(i.attrib['width']) * int(i.attrib['height'])))
images = sorted(images, key=lambda i: (
-1 * int(i.attrib['width']) * int(i.attrib['height'])
))
if not images:
images = tree.xpath("//img[@src]")
if images:
og['og:image'] = images[0].attrib['src']
# pre-cache the image for posterity
# FIXME: it might be cleaner to use the same flow as the main /preview_url request itself
# and benefit from the same caching etc. But for now we just rely on the caching
# of the master request to speed things up.
# FIXME: it might be cleaner to use the same flow as the main /preview_url request
# itself and benefit from the same caching etc. But for now we just rely on the
# caching on the master request to speed things up.
if 'og:image' in og and og['og:image']:
image_info = yield self._download_url(self._rebase_url(og['og:image'], media_info['uri']), requester.user)
image_info = yield self._download_url(
self._rebase_url(og['og:image'], media_info['uri']), requester.user
)
if self._is_media(image_info['media_type']):
# TODO: make sure we don't choke on white-on-transparent images
dims = yield self._generate_local_thumbnails(
image_info['filesystem_id'], image_info
)
image_info['filesystem_id'], image_info
)
if dims:
og["og:image:width"] = dims['width']
og["og:image:height"] = dims['height']
else:
logger.warn("Couldn't get dims for %s" % og["og:image"])
og["og:image"] = "mxc://%s/%s" % (self.server_name, image_info['filesystem_id'])
og["og:image"] = "mxc://%s/%s" % (
self.server_name, image_info['filesystem_id']
)
og["og:image:type"] = image_info['media_type']
else:
del og["og:image"]
if 'og:description' not in og:
meta_description = tree.xpath("//*/meta[translate(@name, 'DESCRIPTION', 'description')='description']/@content");
meta_description = tree.xpath(
"//*/meta"
"[translate(@name, 'DESCRIPTION', 'description')='description']"
"/@content")
if meta_description:
og['og:description'] = meta_description[0]
else:
# text_nodes = tree.xpath("//h1/text() | //h2/text() | //h3/text() | //p/text() | //div/text() | //span/text() | //a/text()")
text_nodes = tree.xpath("//text()[not(ancestor::header | ancestor::nav | ancestor::aside | " +
"ancestor::footer | ancestor::script | ancestor::style)]" +
# text_nodes = tree.xpath("//h1/text() | //h2/text() | //h3/text() | "
# "//p/text() | //div/text() | //span/text() | //a/text()")
text_nodes = tree.xpath("//text()[not(ancestor::header | ancestor::nav | "
"ancestor::aside | ancestor::footer | "
"ancestor::script | ancestor::style)]" +
"[ancestor::body]")
text = ''
for text_node in text_nodes:
@ -280,15 +296,16 @@ class PreviewUrlResource(BaseMediaResource):
text = text.strip()[:500]
og['og:description'] = text if text else None
# TODO: delete the url downloads to stop diskfilling, as we only ever cared about its OG
defer.returnValue(og);
# TODO: delete the url downloads to stop diskfilling,
# as we only ever cared about its OG
defer.returnValue(og)
def _rebase_url(self, url, base):
base = list(urlparse(base))
url = list(urlparse(url))
if not url[0]: # fix up schema
if not url[0]: # fix up schema
url[0] = base[0] or "http"
if not url[1]: # fix up hostname
if not url[1]: # fix up hostname
url[1] = base[1]
if not url[2].startswith('/'):
url[2] = re.sub(r'/[^/]+$', '/', base[2]) + url[2]
@ -377,6 +394,8 @@ class PreviewUrlResource(BaseMediaResource):
def _is_html(self, content_type):
content_type = content_type.lower()
if (content_type.startswith("text/html") or
content_type.startswith("application/xhtml")):
if (
content_type.startswith("text/html") or
content_type.startswith("application/xhtml")
):
return True

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@ -87,7 +87,8 @@ class MediaRepositoryStore(SQLBaseStore):
"get_url_cache", get_url_cache_txn
)
def store_url_cache(self, url, response_code, etag, expires, og, media_id, download_ts):
def store_url_cache(self, url, response_code, etag, expires, og, media_id,
download_ts):
return self._simple_insert(
"local_media_repository_url_cache",
{