From 04da8725ed07447ab15ea447f2a01d64f9539ce8 Mon Sep 17 00:00:00 2001
From: Thomas Sileo <t@a4.io>
Date: Mon, 12 Sep 2022 08:04:16 +0200
Subject: [PATCH] Improve fetch

---
 app/activitypub.py        | 6 ++++++
 app/admin.py              | 2 ++
 app/httpsig.py            | 7 ++-----
 app/templates/lookup.html | 2 ++
 4 files changed, 12 insertions(+), 5 deletions(-)

diff --git a/app/activitypub.py b/app/activitypub.py
index 968929d..e3ddac9 100644
--- a/app/activitypub.py
+++ b/app/activitypub.py
@@ -61,6 +61,10 @@ class ObjectNotFoundError(Exception):
     pass
 
 
+class ObjectUnavailableError(Exception):
+    pass
+
+
 class FetchErrorTypeEnum(str, enum.Enum):
     TIMEOUT = "TIMEOUT"
     NOT_FOUND = "NOT_FOUND"
@@ -167,6 +171,8 @@ async def fetch(
     # Special handling for deleted object
     if resp.status_code == 410:
         raise ObjectIsGoneError(f"{url} is gone")
+    elif resp.status_code in [401, 403]:
+        raise ObjectUnavailableError(f"not allowed to fetch {url}")
     elif resp.status_code == 404:
         raise ObjectNotFoundError(f"{url} not found")
 
diff --git a/app/admin.py b/app/admin.py
index 3a72889..621a8ac 100644
--- a/app/admin.py
+++ b/app/admin.py
@@ -85,6 +85,8 @@ async def get_lookup(
             error = ap.FetchErrorTypeEnum.TIMEOUT
         except (ap.ObjectNotFoundError, ap.ObjectIsGoneError):
             error = ap.FetchErrorTypeEnum.NOT_FOUND
+        except (ap.ObjectUnavailableError):
+            error = ap.FetchErrorTypeEnum.UNAUHTORIZED
         except Exception:
             logger.exception(f"Failed to lookup {query}")
             error = ap.FetchErrorTypeEnum.INTERNAL_ERROR
diff --git a/app/httpsig.py b/app/httpsig.py
index 7691c2b..583901d 100644
--- a/app/httpsig.py
+++ b/app/httpsig.py
@@ -115,11 +115,8 @@ async def _get_public_key(db_session: AsyncSession, key_id: str) -> Key:
     # might race to fetch each other key
     try:
         actor = await ap.fetch(key_id, disable_httpsig=True)
-    except httpx.HTTPStatusError as http_err:
-        if http_err.response.status_code in [401, 403]:
-            actor = await ap.fetch(key_id, disable_httpsig=False)
-        else:
-            raise
+    except ap.ObjectUnavailableError:
+        actor = await ap.fetch(key_id, disable_httpsig=False)
 
     if actor["type"] == "Key":
         # The Key is not embedded in the Person
diff --git a/app/templates/lookup.html b/app/templates/lookup.html
index 611a944..0b077e2 100644
--- a/app/templates/lookup.html
+++ b/app/templates/lookup.html
@@ -20,6 +20,8 @@
     <div class="box error-box">
         {% if error.value == "NOT_FOUND" %}
         <p>The remote object is unavailable.</p>
+        {% elif error.value == "UNAUTHORIZED" %}
+        <p>Missing permissions to fetch the remote object.</p>
         {% elif error.value == "TIMEOUT" %}
         <p>Lookup timed out, please try refreshing the page.</p>
         {% else %}