diff options
| -rw-r--r-- | changelog.d/15092.bugfix | 1 | ||||
| -rw-r--r-- | synapse/rest/media/v1/preview_url_resource.py | 33 | ||||
| -rw-r--r-- | tests/rest/media/v1/test_url_preview.py | 44 |
3 files changed, 65 insertions, 13 deletions
diff --git a/changelog.d/15092.bugfix b/changelog.d/15092.bugfix new file mode 100644 index 0000000000..67509c5c69 --- /dev/null +++ b/changelog.d/15092.bugfix @@ -0,0 +1 @@ +Fix a long-standing bug where a URL preview would break if the discovered oEmbed failed to download. diff --git a/synapse/rest/media/v1/preview_url_resource.py b/synapse/rest/media/v1/preview_url_resource.py index a8f6fd6b35..4a594ab9d8 100644 --- a/synapse/rest/media/v1/preview_url_resource.py +++ b/synapse/rest/media/v1/preview_url_resource.py @@ -163,6 +163,10 @@ class PreviewUrlResource(DirectServeJsonResource): 7. Stores the result in the database cache. 4. Returns the result. + If any additional requests (e.g. from oEmbed autodiscovery, step 5.3 or + image thumbnailing, step 5.4 or 6.4) fails then the URL preview as a whole + does not fail. As much information as possible is returned. + The in-memory cache expires after 1 hour. Expired entries in the database cache (and their associated media files) are @@ -364,16 +368,25 @@ class PreviewUrlResource(DirectServeJsonResource): oembed_url = self._oembed.autodiscover_from_html(tree) og_from_oembed: JsonDict = {} if oembed_url: - oembed_info = await self._handle_url( - oembed_url, user, allow_data_urls=True - ) - ( - og_from_oembed, - author_name, - expiration_ms, - ) = await self._handle_oembed_response( - url, oembed_info, expiration_ms - ) + try: + oembed_info = await self._handle_url( + oembed_url, user, allow_data_urls=True + ) + except Exception as e: + # Fetching the oEmbed info failed, don't block the entire URL preview. + logger.warning( + "oEmbed fetch failed during URL preview: %s errored with %s", + oembed_url, + e, + ) + else: + ( + og_from_oembed, + author_name, + expiration_ms, + ) = await self._handle_oembed_response( + url, oembed_info, expiration_ms + ) # Parse Open Graph information from the HTML in case the oEmbed # response failed or is incomplete. diff --git a/tests/rest/media/v1/test_url_preview.py b/tests/rest/media/v1/test_url_preview.py index 6fcf60ce19..2acfccec61 100644 --- a/tests/rest/media/v1/test_url_preview.py +++ b/tests/rest/media/v1/test_url_preview.py @@ -657,7 +657,7 @@ class URLPreviewTests(unittest.HomeserverTestCase): """If the preview image doesn't exist, ensure some data is returned.""" self.lookups["matrix.org"] = [(IPv4Address, "10.1.2.3")] - end_content = ( + result = ( b"""<html><body><img src="http://cdn.matrix.org/foo.jpg"></body></html>""" ) @@ -678,8 +678,8 @@ class URLPreviewTests(unittest.HomeserverTestCase): b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\n" b'Content-Type: text/html; charset="utf8"\r\n\r\n' ) - % (len(end_content),) - + end_content + % (len(result),) + + result ) self.pump() @@ -688,6 +688,44 @@ class URLPreviewTests(unittest.HomeserverTestCase): # The image should not be in the result. self.assertNotIn("og:image", channel.json_body) + def test_oembed_failure(self) -> None: + """If the autodiscovered oEmbed URL fails, ensure some data is returned.""" + self.lookups["matrix.org"] = [(IPv4Address, "10.1.2.3")] + + result = b""" + <title>oEmbed Autodiscovery Fail</title> + <link rel="alternate" type="application/json+oembed" + href="http://example.com/oembed?url=http%3A%2F%2Fmatrix.org&format=json" + title="matrixdotorg" /> + """ + + channel = self.make_request( + "GET", + "preview_url?url=http://matrix.org", + shorthand=False, + await_result=False, + ) + self.pump() + + client = self.reactor.tcpClients[0][2].buildProtocol(None) + server = AccumulatingProtocol() + server.makeConnection(FakeTransport(client, self.reactor)) + client.makeConnection(FakeTransport(server, self.reactor)) + client.dataReceived( + ( + b"HTTP/1.0 200 OK\r\nContent-Length: %d\r\n" + b'Content-Type: text/html; charset="utf8"\r\n\r\n' + ) + % (len(result),) + + result + ) + + self.pump() + self.assertEqual(channel.code, 200) + + # The image should not be in the result. + self.assertEqual(channel.json_body["og:title"], "oEmbed Autodiscovery Fail") + def test_data_url(self) -> None: """ Requesting to preview a data URL is not supported. |