[Bugfix][Router]: reconfigure callbacks with dynamic config

src/vllm_router/app.py

@@ -41,7 +41,7 @@
     initialize_service_discovery,
 )
 from vllm_router.services.batch_service import initialize_batch_processor
-from vllm_router.services.callbacks_service.callbacks import initialize_custom_callbacks
+from vllm_router.services.callbacks_service.callbacks import configure_custom_callbacks
 from vllm_router.services.files_service import initialize_storage
 from vllm_router.services.request_service.rewriter import (
     get_request_rewriter,
@@ -195,7 +195,7 @@ def initialize_all(app: FastAPI, args):
             )
 
     if args.callbacks:
-        initialize_custom_callbacks(args.callbacks, app)
+        configure_custom_callbacks(args.callbacks, app)
 
     initialize_routing_logic(
         args.routing_logic,

src/vllm_router/dynamic_config.py

@@ -29,6 +29,7 @@
     ServiceDiscoveryType,
     reconfigure_service_discovery,
 )
+from vllm_router.services.callbacks_service.callbacks import configure_custom_callbacks
 from vllm_router.utils import (
     SingletonMeta,
     parse_comma_separated_args,
@@ -223,6 +224,15 @@ def reconfigure_stats(self, config: DynamicRouterConfig):
         # TODO (ApostaC): Implement reconfigure_stats
         pass
 
+    def reconfigure_callbacks(self, config: DynamicRouterConfig):
+        """
+        Reconfigures the router with the given config.
+        """
+        if config.callbacks:
+            configure_custom_callbacks(config.callbacks, self.app)
+        else:
+            self.app.state.callbacks = None
+
     def reconfigure_all(self, config: DynamicRouterConfig):
         """
         Reconfigures the router with the given config.
@@ -231,6 +241,7 @@ def reconfigure_all(self, config: DynamicRouterConfig):
         self.reconfigure_routing_logic(config)
         self.reconfigure_batch_api(config)
         self.reconfigure_stats(config)
+        self.reconfigure_callbacks(config)
 
     def _sleep_or_break(self, check_interval: float = 1):
         """

src/vllm_router/services/callbacks_service/callbacks.py

@@ -20,7 +20,7 @@
 logger = init_logger(__name__)
 
 
-def initialize_custom_callbacks(callbacks_file_location: str, app: FastAPI):
+def configure_custom_callbacks(callbacks_file_location: str, app: FastAPI):
     # Split the path by dots to separate module from instance
     parts = callbacks_file_location.split(".")
 

src/vllm_router/services/request_service/request.py

@@ -130,7 +130,7 @@ async def process_request(
         await store_in_semantic_cache(
             endpoint=endpoint, method=request.method, body=body, chunk=cache_chunk
         )
-    if background_tasks and hasattr(request.app.state, "callbacks"):
+    if background_tasks and getattr(request.app.state, "callbacks", None):
         background_tasks.add_task(
             request.app.state.callbacks.post_request, request, full_response
         )
@@ -170,7 +170,7 @@ async def route_general_request(
     else:
         request_endpoint = None
 
-    if hasattr(request.app.state, "callbacks") and (
+    if getattr(request.app.state, "callbacks", None) and (
         response_overwrite := request.app.state.callbacks.pre_request(
             request, request_body, request_json
         )