Add client_resp.raise_for_status()

aiohttp/client_reqrep.py

@@ -691,6 +691,12 @@ def release(self):
                 self._connection = None
             self._cleanup_writer()
 
+    def raise_for_status(self):
+        if 400 <= self.status:
+            raise aiohttp.HttpProcessingError(
+                code=self.status,
+                message=self.reason)
+
     def _cleanup_writer(self):
         if self._writer is not None and not self._writer.done():
             self._writer.cancel()

docs/client_reference.rst

@@ -1147,6 +1147,11 @@ Response object
       return it into free connection pool for re-usage by next upcoming
       request.
 
+   .. method:: raise_for_status()
+
+      Raise an HttpProcessingError if the response status is 400 or higher.
+      Do nothing for success responses (less than 400).
+
    .. comethod:: text(encoding=None)
 
       Read response's body and return decoded :class:`str` using

tests/test_client_response.py

@@ -274,3 +274,16 @@ def test_close_deprecated(self):
         with self.assertWarns(DeprecationWarning):
             self.response.close(force=False)
         self.assertIsNone(self.response._connection)
+
+    def test_raise_for_status_2xx(self):
+        self.response.status = 200
+        self.response.reason = 'OK'
+        self.response.raise_for_status()  # should not raise
+
+    def test_raise_for_status_4xx(self):
+        self.response.status = 409
+        self.response.reason = 'CONFLICT'
+        with self.assertRaises(aiohttp.HttpProcessingError) as cm:
+            self.response.raise_for_status()
+        self.assertEqual(str(cm.exception.code), '409')
+        self.assertEqual(str(cm.exception.message), "CONFLICT")