Tweak lookup

utils/lookup.py

@@ -4,6 +4,7 @@ import little_boxes.activitypub as ap
 import mf2py
 import requests
 from little_boxes.errors import NotAnActivityError
+from little_boxes.errors import RemoteServerUnavailableError
 from little_boxes.webfinger import get_actor_url
 
 
@@ -20,14 +21,20 @@ def lookup(url: str) -> ap.BaseActivity:
         # Some websites may returns 404, 503 or others when they don't support webfinger, and we're just taking a guess
         # when performing the lookup.
         pass
+    except requests.RequestException as err:
+        raise RemoteServerUnavailableError(f"failed to fetch {url}: {err!r}")
 
     backend = ap.get_backend()
-    resp = requests.get(
-        url,
-        timeout=15,
-        allow_redirects=False,
-        headers={"User-Agent": backend.user_agent()},
-    )
+    try:
+        resp = requests.head(
+            url,
+            timeout=10,
+            allow_redirects=True,
+            headers={"User-Agent": backend.user_agent()},
+        )
+    except requests.RequestException as err:
+        raise RemoteServerUnavailableError(f"failed to GET {url}: {err!r}")
+
     resp.raise_for_status()
 
     # If the page is HTML, maybe it contains an alternate link pointing to an AP object