synapse-product/synapse/http/content_repository.py
2014-11-20 17:26:36 +00:00

213 lines
7.9 KiB
Python

# -*- coding: utf-8 -*-
# Copyright 2014 OpenMarket Ltd
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from .server import respond_with_json_bytes
from synapse.util.stringutils import random_string
from synapse.api.errors import (
cs_exception, SynapseError, CodeMessageException, Codes, cs_error
)
from twisted.protocols.basic import FileSender
from twisted.web import server, resource
from twisted.internet import defer
import base64
import json
import logging
import os
import re
logger = logging.getLogger(__name__)
class ContentRepoResource(resource.Resource):
"""Provides file uploading and downloading.
Uploads are POSTed to wherever this Resource is linked to. This resource
returns a "content token" which can be used to GET this content again. The
token is typically a path, but it may not be. Tokens can expire, be
one-time uses, etc.
In this case, the token is a path to the file and contains 3 interesting
sections:
- User ID base64d (for namespacing content to each user)
- random 24 char string
- Content type base64d (so we can return it when clients GET it)
"""
isLeaf = True
def __init__(self, hs, directory, auth, external_addr):
resource.Resource.__init__(self)
self.hs = hs
self.directory = directory
self.auth = auth
self.external_addr = external_addr.rstrip('/')
self.max_upload_size = hs.config.max_upload_size
if not os.path.isdir(self.directory):
os.mkdir(self.directory)
logger.info("ContentRepoResource : Created %s directory.",
self.directory)
@defer.inlineCallbacks
def map_request_to_name(self, request):
# auth the user
auth_user = yield self.auth.get_user_by_req(request)
# namespace all file uploads on the user
prefix = base64.urlsafe_b64encode(
auth_user.to_string()
).replace('=', '')
# use a random string for the main portion
main_part = random_string(24)
# suffix with a file extension if we can make one. This is nice to
# provide a hint to clients on the file information. We will also reuse
# this info to spit back the content type to the client.
suffix = ""
if request.requestHeaders.hasHeader("Content-Type"):
content_type = request.requestHeaders.getRawHeaders(
"Content-Type")[0]
suffix = "." + base64.urlsafe_b64encode(content_type)
if (content_type.split("/")[0].lower() in
["image", "video", "audio"]):
file_ext = content_type.split("/")[-1]
# be a little paranoid and only allow a-z
file_ext = re.sub("[^a-z]", "", file_ext)
suffix += "." + file_ext
file_name = prefix + main_part + suffix
file_path = os.path.join(self.directory, file_name)
logger.info("User %s is uploading a file to path %s",
auth_user.to_string(),
file_path)
# keep trying to make a non-clashing file, with a sensible max attempts
attempts = 0
while os.path.exists(file_path):
main_part = random_string(24)
file_name = prefix + main_part + suffix
file_path = os.path.join(self.directory, file_name)
attempts += 1
if attempts > 25: # really? Really?
raise SynapseError(500, "Unable to create file.")
defer.returnValue(file_path)
def render_GET(self, request):
# no auth here on purpose, to allow anyone to view, even across home
# servers.
# TODO: A little crude here, we could do this better.
filename = request.path.split('/')[-1]
# be paranoid
filename = re.sub("[^0-9A-z.-_]", "", filename)
file_path = self.directory + "/" + filename
logger.debug("Searching for %s", file_path)
if os.path.isfile(file_path):
# filename has the content type
base64_contentype = filename.split(".")[1]
content_type = base64.urlsafe_b64decode(base64_contentype)
logger.info("Sending file %s", file_path)
f = open(file_path, 'rb')
request.setHeader('Content-Type', content_type)
# cache for at least a day.
# XXX: we might want to turn this off for data we don't want to
# recommend caching as it's sensitive or private - or at least
# select private. don't bother setting Expires as all our matrix
# clients are smart enough to be happy with Cache-Control (right?)
request.setHeader(
"Cache-Control", "public,max-age=86400,s-maxage=86400"
)
d = FileSender().beginFileTransfer(f, request)
# after the file has been sent, clean up and finish the request
def cbFinished(ignored):
f.close()
request.finish()
d.addCallback(cbFinished)
else:
respond_with_json_bytes(
request,
404,
json.dumps(cs_error("Not found", code=Codes.NOT_FOUND)),
send_cors=True)
return server.NOT_DONE_YET
def render_POST(self, request):
self._async_render(request)
return server.NOT_DONE_YET
def render_OPTIONS(self, request):
respond_with_json_bytes(request, 200, {}, send_cors=True)
return server.NOT_DONE_YET
@defer.inlineCallbacks
def _async_render(self, request):
try:
# TODO: The checks here are a bit late. The content will have
# already been uploaded to a tmp file at this point
content_length = request.getHeader("Content-Length")
if content_length is None:
raise SynapseError(
msg="Request must specify a Content-Length", code=400
)
if int(content_length) > self.max_upload_size:
raise SynapseError(
msg="Upload request body is too large",
code=413,
)
fname = yield self.map_request_to_name(request)
# TODO I have a suspcious feeling this is just going to block
with open(fname, "wb") as f:
f.write(request.content.read())
# FIXME (erikj): These should use constants.
file_name = os.path.basename(fname)
# FIXME: we can't assume what the repo's public mounted path is
# ...plus self-signed SSL won't work to remote clients anyway
# ...and we can't assume that it's SSL anyway, as we might want to
# server it via the non-SSL listener...
url = "%s/_matrix/content/%s" % (
self.external_addr, file_name
)
respond_with_json_bytes(request, 200,
json.dumps({"content_token": url}),
send_cors=True)
except CodeMessageException as e:
logger.exception(e)
respond_with_json_bytes(request, e.code,
json.dumps(cs_exception(e)))
except Exception as e:
logger.error("Failed to store file: %s" % e)
respond_with_json_bytes(
request,
500,
json.dumps({"error": "Internal server error"}),
send_cors=True)