Add real ip detection to asgi integration (#1199)

Closes #1154

Author: augustozanellato

sentry_sdk/integrations/asgi.py

@@ -171,7 +171,7 @@ def event_processor(self, event, hint, asgi_scope):
 
         client = asgi_scope.get("client")
         if client and _should_send_default_pii():
-            request_info["env"] = {"REMOTE_ADDR": client[0]}
+            request_info["env"] = {"REMOTE_ADDR": self._get_ip(asgi_scope)}
 
         if (
             event.get("transaction", _DEFAULT_TRANSACTION_NAME)
@@ -225,6 +225,20 @@ def _get_query(self, scope):
             return None
         return urllib.parse.unquote(qs.decode("latin-1"))
 
+    def _get_ip(self, scope):
+        # type: (Any) -> str
+        try:
+            return scope["headers"]["x_forwarded_for"].split(",")[0].strip()
+        except (KeyError, IndexError):
+            pass
+
+        try:
+            return scope["headers"]["x_real_ip"]
+        except KeyError:
+            pass
+
+        return scope.get("client")[0]
+
     def _get_headers(self, scope):
         # type: (Any) -> Dict[str, str]
         """

tests/integrations/asgi/test_asgi.py

@@ -251,3 +251,44 @@ def kangaroo_handler(request):
             }
         )
     )
+
+
+def test_x_forwarded_for(sentry_init, app, capture_events):
+    sentry_init(send_default_pii=True)
+    events = capture_events()
+
+    client = TestClient(app)
+    response = client.get("/", headers={"X-Forwarded-For": "testproxy"})
+
+    assert response.status_code == 200
+
+    (event,) = events
+    assert event["request"]["env"] == {"REMOTE_ADDR": "testproxy"}
+
+
+def test_x_forwarded_for_multiple_entries(sentry_init, app, capture_events):
+    sentry_init(send_default_pii=True)
+    events = capture_events()
+
+    client = TestClient(app)
+    response = client.get(
+        "/", headers={"X-Forwarded-For": "testproxy1,testproxy2,testproxy3"}
+    )
+
+    assert response.status_code == 200
+
+    (event,) = events
+    assert event["request"]["env"] == {"REMOTE_ADDR": "testproxy1"}
+
+
+def test_x_real_ip(sentry_init, app, capture_events):
+    sentry_init(send_default_pii=True)
+    events = capture_events()
+
+    client = TestClient(app)
+    response = client.get("/", headers={"X-Real-IP": "1.2.3.4"})
+
+    assert response.status_code == 200
+
+    (event,) = events
+    assert event["request"]["env"] == {"REMOTE_ADDR": "1.2.3.4"}