Fediverse: Add support for missing host-meta document

plugins/Fediverse/activitypub.py

@@ -61,10 +61,6 @@ class ProtocolError(ActivityPubError):
     pass
 
 
-class HostmetaError(ProtocolError):
-    pass
-
-
 class ActivityPubProtocolError(ActivityPubError):
     pass
 
@@ -118,7 +114,7 @@ def convert_exceptions(to_class, msg="", from_none=False):
 
 @sandbox
 def _get_webfinger_url(hostname):
-    with convert_exceptions(HostmetaError):
+    try:
         doc = ET.fromstring(
             web.getUrlContent("https://%s/.well-known/host-meta" % hostname)
         )
@@ -126,8 +122,9 @@ def _get_webfinger_url(hostname):
         for link in doc.iter(XRD_URI + "Link"):
             if link.attrib["rel"] == "lrdd":
                 return link.attrib["template"]
-
-    return "https://%s/.well-known/webfinger?resource={uri}"
+    except web.Error:
+        # Fall back to the default Webfinger URL
+        return "https://%s/.well-known/webfinger?resource={uri}" % hostname
 
 
 def has_webfinger_support(hostname):

plugins/Fediverse/test.py

@@ -255,6 +255,19 @@ class NetworklessFediverseTestCase(BaseFediverseTestCase):
                 "\x02someuser\x02 (@someuser@example.org): My Biography",
             )
 
+    def testProfileNoHostmeta(self):
+        expected_requests = [
+            (HOSTMETA_URL, utils.web.Error("blah")),
+            (WEBFINGER_URL, WEBFINGER_DATA),
+            (ACTOR_URL, ACTOR_DATA),
+        ]
+
+        with self.mockRequests(expected_requests):
+            self.assertResponse(
+                "profile @someuser@example.org",
+                "\x02someuser\x02 (@someuser@example.org): My Biography",
+            )
+
     def testProfileSnarfer(self):
         with self.mockWebfingerSupport("not called"), self.mockRequests([]):
             self.assertSnarfNoResponse("aaa @nonexistinguser@example.org bbb")