Retry once on remote protocol errors (#80)

Author: bdraco

onvif/client.py

@@ -96,6 +96,23 @@ def original_load(self, *args: Any, **kwargs: Any) -> None:
         return original_load(self, *args, **kwargs)
 
 
+class AsyncTransportProtocolErrorHandler(AsyncTransport):
+    """Retry on remote protocol error.
+
+    http://datatracker.ietf.org/doc/html/rfc2616#section-8.1.4 allows the server
+    # to close the connection at any time, we treat this as a normal and try again
+    # once since
+    """
+
+    @retry_connection_error(attempts=2, exception=httpx.RemoteProtocolError)
+    async def post(self, address, message, headers):
+        return await super().post(address, message, headers)
+
+    @retry_connection_error(attempts=2, exception=httpx.RemoteProtocolError)
+    async def get(self, address, params, headers):
+        return await super().get(address, params, headers)
+
+
 async def _cached_document(url: str) -> Document:
     """Load external XML document from disk."""
     if url in _DOCUMENT_CACHE:
@@ -223,9 +240,9 @@ def __init__(
             verify=_NO_VERIFY_SSL_CONTEXT, timeout=timeouts, limits=_HTTPX_LIMITS
         )
         self.transport = (
-            AsyncTransport(client=client, wsdl_client=wsdl_client)
+            AsyncTransportProtocolErrorHandler(client=client, wsdl_client=wsdl_client)
             if no_cache
-            else AsyncTransport(
+            else AsyncTransportProtocolErrorHandler(
                 client=client, wsdl_client=wsdl_client, cache=SqliteCache()
             )
         )

onvif/wrappers.py

@@ -19,6 +19,7 @@
 
 def retry_connection_error(
     attempts: int = DEFAULT_ATTEMPTS,
+    exception: httpx.HTTPError = httpx.RequestError,
 ) -> Callable[[Callable[P, Awaitable[T]]], Callable[P, Awaitable[T]]]:
     """Define a wrapper to retry on connection error."""
 
@@ -37,7 +38,7 @@ async def _async_wrap_connection_error_retry(  # type: ignore[return]
             for attempt in range(attempts):
                 try:
                     return await func(*args, **kwargs)
-                except httpx.RequestError as ex:
+                except exception as ex:
                     #
                     # We should only need to retry on RemoteProtocolError but some cameras
                     # are flakey and sometimes do not respond to the Renew request so we