From 39a40e4dae8da8b6e7072fcbee2fc745c27c016d Mon Sep 17 00:00:00 2001
From: Michael Manfre <mike@manfre.net>
Date: Tue, 6 Dec 2022 23:59:05 -0500
Subject: [PATCH] Set a Takahe User-Agent header for signed requests (#142)

---
 activities/models/post.py | 6 +++++-
 core/signatures.py        | 4 ++++
 takahe/settings.py        | 6 ++++++
 3 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/activities/models/post.py b/activities/models/post.py
index 1017694..b0c89ac 100644
--- a/activities/models/post.py
+++ b/activities/models/post.py
@@ -5,6 +5,7 @@ from typing import Optional
 import httpx
 import urlman
 from asgiref.sync import async_to_sync, sync_to_async
+from django.conf import settings
 from django.contrib.postgres.indexes import GinIndex
 from django.db import models, transaction
 from django.template.defaultfilters import linebreaks_filter
@@ -696,7 +697,10 @@ class Post(StatorModel):
         """
         response = httpx.get(
             self.object_uri,
-            headers={"Accept": "application/json"},
+            headers={
+                "Accept": "application/json",
+                "User-Agent": settings.TAKAHE_USER_AGENT,
+            },
             follow_redirects=True,
         )
         if 200 <= response.status_code < 300:
diff --git a/core/signatures.py b/core/signatures.py
index d0443c3..45e6ff4 100644
--- a/core/signatures.py
+++ b/core/signatures.py
@@ -220,6 +220,10 @@ class HttpSignature:
                 "algorithm": "rsa-sha256",
             }
         )
+
+        # Announce ourselves with an agent similar to Mastodon
+        headers["User-Agent"] = settings.TAKAHE_USER_AGENT
+
         # Send the request with all those headers except the pseudo one
         del headers["(request-target)"]
         async with httpx.AsyncClient(timeout=timeout) as client:
diff --git a/takahe/settings.py b/takahe/settings.py
index 981bb96..f508952 100644
--- a/takahe/settings.py
+++ b/takahe/settings.py
@@ -7,6 +7,7 @@ from typing import Literal
 
 import dj_database_url
 import django_cache_url
+import httpx
 import sentry_sdk
 from pydantic import AnyUrl, BaseSettings, EmailStr, Field, validator
 from sentry_sdk.integrations.django import DjangoIntegration
@@ -354,3 +355,8 @@ CACHES = {"default": django_cache_url.parse(SETUP.CACHES_DEFAULT or "dummy://")}
 
 if SETUP.ERROR_EMAILS:
     ADMINS = [("Admin", e) for e in SETUP.ERROR_EMAILS]
+
+TAKAHE_USER_AGENT = (
+    f"python-httpx/{httpx.__version__} "
+    f"(Takahe/{__version__}; +https://{SETUP.MAIN_DOMAIN}/)"
+)