From d5352cbba80005fb226563211c9e7179edef2d65 Mon Sep 17 00:00:00 2001 From: Richard van der Hoff Date: Fri, 2 Feb 2018 00:35:18 +0000 Subject: [PATCH] Handle url_previews with no content-type avoid failing with an exception if the remote server doesn't give us a Content-Type header. Also, clean up the exception handling a bit. --- synapse/rest/media/v1/preview_url_resource.py | 55 ++++++++++++------- 1 file changed, 34 insertions(+), 21 deletions(-) diff --git a/synapse/rest/media/v1/preview_url_resource.py b/synapse/rest/media/v1/preview_url_resource.py index 981f01e417..31fe7aa75c 100644 --- a/synapse/rest/media/v1/preview_url_resource.py +++ b/synapse/rest/media/v1/preview_url_resource.py @@ -12,6 +12,19 @@ # 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. +import cgi +import datetime +import errno +import fnmatch +import itertools +import logging +import os +import re +import shutil +import sys +import traceback +import ujson as json +import urlparse from twisted.web.server import NOT_DONE_YET from twisted.internet import defer @@ -33,18 +46,6 @@ from synapse.http.server import ( 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 urlparse -import itertools -import datetime -import errno -import shutil - -import logging logger = logging.getLogger(__name__) @@ -286,17 +287,28 @@ class PreviewUrlResource(Resource): url_cache=True, ) - try: - with self.media_storage.store_into_file(file_info) as (f, fname, finish): + with self.media_storage.store_into_file(file_info) as (f, fname, finish): + try: 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, ) + except Exception as e: # FIXME: pass through 404s and other error messages nicely + logger.warn("Error downloading %s: %r", url, e) + raise SynapseError( + 500, "Failed to download content: %s" % ( + traceback.format_exception_only(sys.exc_type, e), + ), + Codes.UNKNOWN, + ) + yield finish() - yield finish() - - media_type = headers["Content-Type"][0] + try: + if "Content-Type" in headers: + media_type = headers["Content-Type"][0] + else: + media_type = "application/octet-stream" time_now_ms = self.clock.time_msec() content_disposition = headers.get("Content-Disposition", None) @@ -336,10 +348,11 @@ class PreviewUrlResource(Resource): ) except Exception as e: - raise SynapseError( - 500, ("Failed to download content: %s" % e), - Codes.UNKNOWN - ) + logger.error("Error handling downloaded %s: %r", url, e) + # TODO: we really ought to delete the downloaded file in this + # case, since we won't have recorded it in the db, and will + # therefore not expire it. + raise defer.returnValue({ "media_type": media_type,