diff --git a/synapse/rest/media/v1/base_resource.py b/synapse/rest/media/v1/base_resource.py
index 58ef91c0b8..2b1938dc8e 100644
--- a/synapse/rest/media/v1/base_resource.py
+++ b/synapse/rest/media/v1/base_resource.py
@@ -72,6 +72,7 @@ class BaseMediaResource(Resource):
self.store = hs.get_datastore()
self.max_upload_size = hs.config.max_upload_size
self.max_image_pixels = hs.config.max_image_pixels
+ self.max_spider_size = hs.config.max_spider_size
self.filepaths = filepaths
self.version_string = hs.version_string
self.downloads = {}
diff --git a/synapse/rest/media/v1/media_repository.py b/synapse/rest/media/v1/media_repository.py
index 7dfb027dd1..97b7e84af9 100644
--- a/synapse/rest/media/v1/media_repository.py
+++ b/synapse/rest/media/v1/media_repository.py
@@ -17,6 +17,7 @@ from .upload_resource import UploadResource
from .download_resource import DownloadResource
from .thumbnail_resource import ThumbnailResource
from .identicon_resource import IdenticonResource
+from .preview_url_resource import PreviewUrlResource
from .filepath import MediaFilePaths
from twisted.web.resource import Resource
@@ -78,3 +79,9 @@ class MediaRepositoryResource(Resource):
self.putChild("download", DownloadResource(hs, filepaths))
self.putChild("thumbnail", ThumbnailResource(hs, filepaths))
self.putChild("identicon", IdenticonResource())
+ if hs.config.url_preview_enabled:
+ try:
+ self.putChild("preview_url", PreviewUrlResource(hs, filepaths))
+ except Exception as e:
+ logger.warn("Failed to mount preview_url")
+ logger.exception(e)
diff --git a/synapse/rest/media/v1/preview_url_resource.py b/synapse/rest/media/v1/preview_url_resource.py
new file mode 100644
index 0000000000..8464fc0176
--- /dev/null
+++ b/synapse/rest/media/v1/preview_url_resource.py
@@ -0,0 +1,462 @@
+# -*- coding: utf-8 -*-
+# Copyright 2016 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 .base_resource import BaseMediaResource
+
+from twisted.web.server import NOT_DONE_YET
+from twisted.internet import defer
+from urlparse import urlparse, urlsplit, urlunparse
+
+from synapse.api.errors import (
+ SynapseError, 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_bytes
+)
+from synapse.util.async import ObservableDeferred
+from synapse.util.stringutils import is_ascii
+
+import os
+import re
+import fnmatch
+import cgi
+import ujson as json
+
+import logging
+logger = logging.getLogger(__name__)
+
+try:
+ from lxml import html
+except ImportError:
+ pass
+
+
+class PreviewUrlResource(BaseMediaResource):
+ isLeaf = True
+
+ def __init__(self, hs, filepaths):
+ try:
+ if html:
+ pass
+ except:
+ raise RuntimeError("Disabling PreviewUrlResource as lxml not available")
+
+ if not hasattr(hs.config, "url_preview_ip_range_blacklist"):
+ logger.warn(
+ "For security, you must specify an explicit target IP address "
+ "blacklist in url_preview_ip_range_blacklist for url previewing "
+ "to work"
+ )
+ raise RuntimeError(
+ "Disabling PreviewUrlResource as "
+ "url_preview_ip_range_blacklist not specified"
+ )
+
+ BaseMediaResource.__init__(self, hs, filepaths)
+ self.client = SpiderHttpClient(hs)
+ if hasattr(hs.config, "url_preview_url_blacklist"):
+ self.url_preview_url_blacklist = hs.config.url_preview_url_blacklist
+
+ # simple memory cache mapping urls to OG metadata
+ self.cache = ExpiringCache(
+ 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()
+
+ self.downloads = {}
+
+ def render_GET(self, request):
+ self._async_render_GET(request)
+ return NOT_DONE_YET
+
+ @request_handler
+ @defer.inlineCallbacks
+ def _async_render_GET(self, request):
+
+ # 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]
+ if "ts" in request.args:
+ ts = int(request.args.get("ts")[0])
+ else:
+ ts = self.clock.time_msec()
+
+ # impose the URL pattern blacklist
+ if hasattr(self, "url_preview_url_blacklist"):
+ url_tuple = urlsplit(url)
+ for entry in self.url_preview_url_blacklist:
+ match = True
+ for attrib in entry:
+ pattern = entry[attrib]
+ value = getattr(url_tuple, attrib)
+ logger.debug((
+ "Matching attrib '%s' with value '%s' against"
+ " pattern '%s'"
+ ) % (attrib, value, pattern))
+
+ if value is None:
+ match = False
+ continue
+
+ if pattern.startswith('^'):
+ if not re.match(pattern, getattr(url_tuple, attrib)):
+ match = False
+ continue
+ else:
+ if not fnmatch.fnmatch(getattr(url_tuple, attrib), pattern):
+ match = False
+ continue
+ if match:
+ logger.warn(
+ "URL %s blocked by url_blacklist entry %s", url, entry
+ )
+ raise SynapseError(
+ 403, "URL blocked by url pattern blacklist entry",
+ Codes.UNKNOWN
+ )
+
+ # 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.
+ og = self.cache.get(url)
+ if og:
+ respond_with_json_bytes(request, 200, json.dumps(og), send_cors=True)
+ return
+
+ # then check the URL cache in the DB (which will also provide us with
+ # historical previews, if we have any)
+ cache_result = yield self.store.get_url_cache(url, ts)
+ if (
+ cache_result and
+ cache_result["download_ts"] + cache_result["expires"] > ts and
+ cache_result["response_code"] / 100 == 2
+ ):
+ respond_with_json_bytes(
+ request, 200, cache_result["og"].encode('utf-8'),
+ send_cors=True
+ )
+ return
+
+ # Ensure only one download for a given URL is active at a time
+ download = self.downloads.get(url)
+ if download is None:
+ download = self._download_url(url, requester.user)
+ download = ObservableDeferred(
+ download,
+ consumeErrors=True
+ )
+ self.downloads[url] = download
+
+ @download.addBoth
+ def callback(media_info):
+ del self.downloads[url]
+ return media_info
+ media_info = yield download.observe()
+
+ # FIXME: we should probably update our cache now anyway, so that
+ # even if the OG calculation raises, we don't keep hammering on the
+ # remote server. For now, leave it uncached to aid debugging OG
+ # calculation problems
+
+ logger.debug("got media_info of '%s'" % media_info)
+
+ if self._is_media(media_info['media_type']):
+ dims = yield self._generate_local_thumbnails(
+ 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'],
+ "matrix:image:size": media_info['media_length'],
+ }
+
+ if dims:
+ og["og:image:width"] = dims['width']
+ og["og:image:height"] = dims['height']
+ else:
+ logger.warn("Couldn't get dims for %s" % url)
+
+ # define our OG response for this media
+ elif self._is_html(media_info['media_type']):
+ # TODO: somehow stop a big HTML tree from exploding synapse's RAM
+
+ try:
+ tree = html.parse(media_info['filename'])
+ og = yield self._calc_og(tree, media_info, requester)
+ except UnicodeDecodeError:
+ # XXX: evil evil bodge
+ # Empirically, sites like google.com mix Latin-1 and utf-8
+ # encodings in the same page. The rogue Latin-1 characters
+ # cause lxml to choke with a UnicodeDecodeError, so if we
+ # see this we go and do a manual decode of the HTML before
+ # handing it to lxml as utf-8 encoding, counter-intuitively,
+ # which seems to make it happier...
+ file = open(media_info['filename'])
+ body = file.read()
+ file.close()
+ 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))
+
+ # store OG in ephemeral in-memory cache
+ self.cache[url] = og
+
+ # store OG in history-aware DB cache
+ yield self.store.store_url_cache(
+ url,
+ media_info["response_code"],
+ media_info["etag"],
+ media_info["expires"],
+ json.dumps(og),
+ media_info["filesystem_id"],
+ media_info["created_ts"],
+ )
+
+ respond_with_json_bytes(request, 200, json.dumps(og), send_cors=True)
+
+
+ @defer.inlineCallbacks
+ def _calc_og(self, tree, media_info, requester):
+ # 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" : "video",
+ # "og:url" : "https://www.youtube.com/watch?v=LXDBoHyjmtw",
+ # "og:site_name" : "YouTube",
+ # "og:video:type" : "application/x-shockwave-flash",
+ # "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",
+
+ og = {}
+ for tag in tree.xpath("//*/meta[starts-with(@property, 'og:')]"):
+ og[tag.attrib['property']] = tag.attrib['content']
+
+ # TODO: grab article: meta tags too, e.g.:
+
+ # "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"
+ )
+ 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'])
+ ))
+ 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 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
+ )
+
+ 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
+ )
+ 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:type"] = image_info['media_type']
+ og["matrix:image:size"] = image_info['media_length']
+ else:
+ del og["og:image"]
+
+ if 'og:description' not in og:
+ meta_description = tree.xpath(
+ "//*/meta"
+ "[translate(@name, 'DESCRIPTION', 'description')='description']"
+ "/@content")
+ if meta_description:
+ og['og:description'] = meta_description[0]
+ else:
+ # grab any text nodes which are inside the <body/> tag...
+ # unless they are within an HTML5 semantic markup tag...
+ # <header/>, <nav/>, <aside/>, <footer/>
+ # ...or if they are within a <script/> or <style/> tag.
+ # This is a very very very coarse approximation to a plain text
+ # render of the page.
+ 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:
+ if len(text) < 500:
+ text += text_node + ' '
+ else:
+ break
+ text = re.sub(r'[\t ]+', ' ', text)
+ text = re.sub(r'[\t \r\n]*[\r\n]+', '\n', text)
+ 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)
+
+ def _rebase_url(self, url, base):
+ base = list(urlparse(base))
+ url = list(urlparse(url))
+ if not url[0]: # fix up schema
+ url[0] = base[0] or "http"
+ 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]
+ return urlunparse(url)
+
+ @defer.inlineCallbacks
+ def _download_url(self, url, user):
+ # TODO: we should probably honour robots.txt... except in practice
+ # we're most likely being explicitly triggered by a human rather than a
+ # bot, so are we really a robot?
+
+ # XXX: horrible duplication with base_resource's _download_remote_file()
+ file_id = random_string(24)
+
+ fname = self.filepaths.local_media_filepath(file_id)
+ self._makedirs(fname)
+
+ try:
+ with open(fname, "wb") as f:
+ logger.debug("Trying to get url '%s'" % url)
+ length, headers, uri, code = yield self.client.get_file(
+ url, output_stream=f, max_size=self.max_spider_size,
+ )
+ # FIXME: pass through 404s and other error messages nicely
+
+ media_type = headers["Content-Type"][0]
+ time_now_ms = self.clock.time_msec()
+
+ content_disposition = headers.get("Content-Disposition", None)
+ if content_disposition:
+ _, params = cgi.parse_header(content_disposition[0],)
+ download_name = None
+
+ # First check if there is a valid UTF-8 filename
+ download_name_utf8 = params.get("filename*", None)
+ if download_name_utf8:
+ if download_name_utf8.lower().startswith("utf-8''"):
+ download_name = download_name_utf8[7:]
+
+ # If there isn't check for an ascii name.
+ if not download_name:
+ download_name_ascii = params.get("filename", None)
+ if download_name_ascii and is_ascii(download_name_ascii):
+ download_name = download_name_ascii
+
+ if download_name:
+ download_name = urlparse.unquote(download_name)
+ try:
+ download_name = download_name.decode("utf-8")
+ except UnicodeDecodeError:
+ download_name = None
+ else:
+ download_name = None
+
+ yield self.store.store_local_media(
+ media_id=file_id,
+ media_type=media_type,
+ time_now_ms=self.clock.time_msec(),
+ upload_name=download_name,
+ media_length=length,
+ user_id=user,
+ )
+
+ except Exception as e:
+ os.remove(fname)
+ raise SynapseError(
+ 500, ("Failed to download content: %s" % e),
+ Codes.UNKNOWN
+ )
+
+ defer.returnValue({
+ "media_type": media_type,
+ "media_length": length,
+ "download_name": download_name,
+ "created_ts": time_now_ms,
+ "filesystem_id": file_id,
+ "filename": fname,
+ "uri": uri,
+ "response_code": code,
+ # FIXME: we should calculate a proper expiration based on the
+ # Cache-Control and Expire headers. But for now, assume 1 hour.
+ "expires": 60 * 60 * 1000,
+ "etag": headers["ETag"][0] if "ETag" in headers else None,
+ })
+
+ def _is_media(self, content_type):
+ if content_type.lower().startswith("image/"):
+ return True
+
+ def _is_html(self, content_type):
+ content_type = content_type.lower()
+ if (
+ content_type.startswith("text/html") or
+ content_type.startswith("application/xhtml")
+ ):
+ return True
diff --git a/synapse/rest/media/v1/thumbnail_resource.py b/synapse/rest/media/v1/thumbnail_resource.py
index ab52499785..513b445688 100644
--- a/synapse/rest/media/v1/thumbnail_resource.py
+++ b/synapse/rest/media/v1/thumbnail_resource.py
@@ -72,6 +72,11 @@ class ThumbnailResource(BaseMediaResource):
self._respond_404(request)
return
+ if media_info["media_type"] == "image/svg+xml":
+ file_path = self.filepaths.local_media_filepath(media_id)
+ yield self._respond_with_file(request, media_info["media_type"], file_path)
+ return
+
thumbnail_infos = yield self.store.get_local_media_thumbnails(media_id)
if thumbnail_infos:
@@ -103,6 +108,11 @@ class ThumbnailResource(BaseMediaResource):
self._respond_404(request)
return
+ if media_info["media_type"] == "image/svg+xml":
+ file_path = self.filepaths.local_media_filepath(media_id)
+ yield self._respond_with_file(request, media_info["media_type"], file_path)
+ return
+
thumbnail_infos = yield self.store.get_local_media_thumbnails(media_id)
for info in thumbnail_infos:
t_w = info["thumbnail_width"] == desired_width
@@ -138,6 +148,11 @@ class ThumbnailResource(BaseMediaResource):
desired_method, desired_type):
media_info = yield self._get_remote_media(server_name, media_id)
+ if media_info["media_type"] == "image/svg+xml":
+ file_path = self.filepaths.remote_media_filepath(server_name, media_id)
+ yield self._respond_with_file(request, media_info["media_type"], file_path)
+ return
+
thumbnail_infos = yield self.store.get_remote_media_thumbnails(
server_name, media_id,
)
@@ -181,6 +196,11 @@ class ThumbnailResource(BaseMediaResource):
# We should proxy the thumbnail from the remote server instead.
media_info = yield self._get_remote_media(server_name, media_id)
+ if media_info["media_type"] == "image/svg+xml":
+ file_path = self.filepaths.remote_media_filepath(server_name, media_id)
+ yield self._respond_with_file(request, media_info["media_type"], file_path)
+ return
+
thumbnail_infos = yield self.store.get_remote_media_thumbnails(
server_name, media_id,
)
@@ -208,6 +228,8 @@ class ThumbnailResource(BaseMediaResource):
@defer.inlineCallbacks
def _respond_default_thumbnail(self, request, media_info, width, height,
method, m_type):
+ # XXX: how is this meant to work? store.get_default_thumbnails
+ # appears to always return [] so won't this always 404?
media_type = media_info["media_type"]
top_level_type = media_type.split("/")[0]
sub_type = media_type.split("/")[-1].split(";")[0]
|
