goblet · anovis · Oct 18, 2023 · Oct 17, 2023 · Oct 18, 2023 · Oct 18, 2023
diff --git a/.flake8 b/.flake8
@@ -1,7 +1,8 @@
 [flake8]
 max-line-length = 88
-ignore = E501, W503, E266, E203
+ignore = E501, W503, E266, E203, C901
 #E501 line too long
 #W503 line break before binary operator
+#C901 __call__ to complex
 ; exclude = .git,__pycache__,docs
 max-complexity = 15
diff --git a/docs/source/topics.rst b/docs/source/topics.rst
@@ -939,3 +939,18 @@ Multi Container Deployments
 Additional containers are now supported in Cloudrun. See `Google annoucement <https://cloud.google.com/blog/products/serverless/cloud-run-now-supports-multi-container-deployments>`__. 
 You can specify additional containers by using the `cloudrun_container_extra` section in `config.json`. Note you will also need to set the `launchStage` field in `cloudrun` to either `BETA`
 or `ALPHA`. Checkout the examples section for more details. 
+
+Error Handling
+^^^^^^^^^^^^^^
+
+Use the `errorhandler` decorator to handle errors based on its exception class. By default `GobletRouteNotFoundError` is handled by returning a 404 response code.
+
+..code:: python 
+
+   @app.errorhandler("GobletRouteNotFoundError")
+    def handle_missing_route(error):
+        return Response("Custom Error", status_code=404)
+
+    @app.errorhandler("ValueError")
+    def return_error_string(error):
+        return Response(str(error), status_code=200)
diff --git a/examples/main.py b/examples/main.py
@@ -376,15 +376,25 @@ def function_test(x: List[int], y: List[int]) -> List[int]:
     }
 })
 
+# Cloudtask HTTP Target
 @app.cloudtasktarget(name="target")
 def my_target_handler(request):
     ''' handle request '''
     return {}
 
-
+# Enqueue a message using the CloudTask Queue client
 @app.route("/enqueue", methods=["GET"])
 def enqueue():
     payload = {"message": {"title": "enqueue"}}
     client.enqueue(target="target", payload=payload)
     return {}
 
+# Example of handling the GobletRouteNotFoundError with a custom response
+@app.errorhandler("GobletRouteNotFoundError")
+def handle_missing_route(error):
+    return Response("Custom Error", status_code=404)
+
+# Example of handling ValueError.
+@app.errorhandler("ValueError")
+def return_error_string(error):
+    return Response(str(error), status_code=200)
diff --git a/goblet/decorators.py b/goblet/decorators.py
@@ -346,6 +346,13 @@ def vpcconnector(self, name, **kwargs):
             kwargs={"name": name, "kwargs": kwargs},
         )
 
+    def errorhandler(self, error):
+        def _register_error_handler(error_handler):
+            self.error_handlers[error] = error_handler
+            return error_handler
+
+        return _register_error_handler
+
     def stage(self, stage=None, stages=[]):
         if not stage and not stages:
             raise ValueError("One of stage or stages should be set")

diff --git a/goblet/errors.py b/goblet/errors.py
@@ -4,3 +4,7 @@ class GobletError(Exception):
 
 class GobletValidationError(Exception):
     pass
+
+
+class GobletRouteNotFoundError(Exception):
+    pass
diff --git a/goblet/handlers/routes.py b/goblet/handlers/routes.py
@@ -15,7 +15,7 @@
 from goblet.utils import get_g_dir
 from goblet.common_cloud_actions import deploy_apigateway, destroy_apigateway
 from goblet.permissions import gcp_generic_resource_permissions
-
+from goblet.errors import GobletRouteNotFoundError
 
 log = logging.getLogger("goblet.deployer")
 log.setLevel(logging.getLevelName(os.getenv("GOBLET_LOG_LEVEL", "INFO")))
@@ -98,7 +98,7 @@ def __call__(self, request, context=None):
                 if "{" in p and self._matched_path(p, path):
                     entry = self.resources.get(p, {}).get(method)
         if not entry:
-            raise ValueError(f"No route found for {path} with {method}")
+            raise GobletRouteNotFoundError(f"No route found for {path} with {method}")
         return entry(request)
 
     @staticmethod

diff --git a/goblet/resource_manager.py b/goblet/resource_manager.py
@@ -26,6 +26,8 @@
 from goblet.infrastructures.cloudtask import CloudTaskQueue
 from goblet.infrastructures.pubsub import PubSubTopic
 
+from goblet.response import default_missing_route
+
 import goblet.globals as g
 
 from goblet.common_cloud_actions import deploy_custom_role, deploy_service_account
@@ -113,6 +115,9 @@ def __init__(
             "before": {},
             "after": {},
         }
+
+        self.error_handlers = {"GobletRouteNotFoundError": default_missing_route}
+
         self.current_request = None
         self.function_name = function_name
 
@@ -127,36 +132,48 @@ def __call__(self, request, context=None):
             added_app.request_context = context
 
         event_type = self.get_event_type(request, context)
-        # call before request middleware
-        request = self._call_middleware(request, event_type, before_or_after="before")
-        response = None
-        if event_type not in EVENT_TYPES:
-            raise ValueError(f"{event_type} not a valid event type")
-        if event_type == "job":
-            response = self.handlers["jobs"](request, context)
-        if event_type == "schedule":
-            response = self.handlers["schedule"](request)
-        if event_type == "pubsub":
-            response = self.handlers["pubsub"](request, context)
-        if event_type == "storage":
-            # Storage trigger can be made with @eventarc decorator
-            try:
-                response = self.handlers["storage"](request, context)
-            except ValueError:
-                event_type = "eventarc"
-        if event_type == "route":
-            response = self.handlers["route"](request)
-        if event_type == "http":
-            response = self.handlers["http"](request)
-        if event_type == "eventarc":
-            response = self.handlers["eventarc"](request)
-        if event_type == "bqremotefunction":
-            response = self.handlers["bqremotefunction"](request)
-        if event_type == "cloudtasktarget":
-            response = self.handlers["cloudtasktarget"](request)
-
-        # call after request middleware
-        response = self._call_middleware(response, event_type, before_or_after="after")
+
+        try:
+            # call before request middleware
+            request = self._call_middleware(
+                request, event_type, before_or_after="before"
+            )
+            response = None
+            if event_type not in EVENT_TYPES:
+                raise ValueError(f"{event_type} not a valid event type")
+            if event_type == "job":
+                response = self.handlers["jobs"](request, context)
+            if event_type == "schedule":
+                response = self.handlers["schedule"](request)
+            if event_type == "pubsub":
+                response = self.handlers["pubsub"](request, context)
+            if event_type == "storage":
+                # Storage trigger can be made with @eventarc decorator
+                try:
+                    response = self.handlers["storage"](request, context)
+                except ValueError:
+                    event_type = "eventarc"
+            if event_type == "route":
+                response = self.handlers["route"](request)
+            if event_type == "http":
+                response = self.handlers["http"](request)
+            if event_type == "eventarc":
+                response = self.handlers["eventarc"](request)
+            if event_type == "bqremotefunction":
+                response = self.handlers["bqremotefunction"](request)
+            if event_type == "cloudtasktarget":
+                response = self.handlers["cloudtasktarget"](request)
+
+            # call after request middleware
+            response = self._call_middleware(
+                response, event_type, before_or_after="after"
+            )
+
+        except Exception as e:
+            if self.error_handlers.get(e.__class__.__name__):
+                return self.error_handlers[e.__class__.__name__](e)
+            raise e
+
         return response
 
     def __add__(self, other):

diff --git a/goblet/response.py b/goblet/response.py
@@ -6,7 +6,7 @@ class Response(object):
     Generic Response class based on Flask Response
     """
 
-    def __init__(self, body, headers=None, status_code=200):
+    def __init__(self, body: str, headers=None, status_code=200):
         self.body = body
         if headers is None:
             headers = {"Content-type": "text/plain"}
@@ -21,3 +21,7 @@ def __call__(self, environ, start_response):
         headers = [(k, v) for k, v in self.headers.items()]
         start_response(status, headers)
         return [body]
+
+
+def default_missing_route(error):
+    return Response(str(error), status_code=404)
diff --git a/goblet/tests/test_app.py b/goblet/tests/test_app.py
@@ -226,11 +226,32 @@ def dummy_function3():
 
         assert len(app.handlers["route"].resources) == 2
 
+    def test_errorhandler_default(self):
+        app = Goblet("test")
 
-# Causes tests to fail
-# class TestGoblet:
+        mock_request = Mock()
+        mock_request.path = "/test"
+        mock_request.method = "GET"
+        mock_request.headers = {}
+        mock_request.json = {}
+
+        assert app(mock_request, {}).status_code == 404
+
+    def test_errorhandler_custom(self):
+        app = Goblet("test")
+
+        mock_request = Mock()
+        mock_request.path = "/error"
+        mock_request.method = "GET"
+        mock_request.headers = {}
+        mock_request.json = {}
+
+        @app.errorhandler("ValueError")
+        def handle_valueError(error):
+            return str(error)
+
+        @app.route("/error")
+        def dummy_function2():
+            raise ValueError("test_error")
 
-#     def test_client_versions(self):
-#         app = Goblet(client_versions={"cloudfunctions":"v2"})
-#         assert app.client_versions["cloudfunctions"] == "v2"
-#         assert app.client_versions["pubsub"] == DEFAULT_CLIENT_VERSIONS["pubsub"]
+        assert app(mock_request, {}) == "test_error"
-Original file line number
+Diff line change
@@ Expand Up / @@ -4,3 +4,7 @@ class GobletError(Exception): @@
     class GobletValidationError(Exception):
         pass
+    class GobletRouteNotFoundError(Exception):
+        pass