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.
This commit is contained in:
Richard van der Hoff 2018-02-02 00:35:18 +00:00
parent 77c0629ebc
commit d5352cbba8

View File

@ -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,