Merge pull request #2922 from cloudflare/maizatskyi/2024-10-14-custom…

…-event-not-supported

CustomEvent::notSupported method to raise appropriate error (if any)

src/workerd/api/hibernatable-web-socket.h

@@ -76,6 +76,10 @@ class HibernatableWebSocketCustomEventImpl final: public WorkerInterface::Custom
     return typeId;
   }
 
+  kj::Promise<Result> notSupported() override {
+    KJ_UNIMPLEMENTED("hibernatable web socket event not supported");
+  }
+
 private:
   // Returns `params`, but if we have a HibernationReader we convert it to a
   // HibernatableSocketParams first.

src/workerd/api/queue.h

@@ -361,6 +361,10 @@ class QueueCustomEventImpl final: public WorkerInterface::CustomEvent, public kj
   kj::Array<QueueRetryMessage> getRetryMessages() const;
   kj::Array<kj::String> getExplicitAcks() const;
 
+  kj::Promise<Result> notSupported() override {
+    KJ_UNIMPLEMENTED("queue event not supported");
+  }
+
 private:
   kj::OneOf<rpc::EventDispatcher::QueueParams::Reader, QueueEvent::Params> params;
   QueueEventResult result;

src/workerd/api/trace.h

@@ -623,6 +623,10 @@ class TraceCustomEventImpl final: public WorkerInterface::CustomEvent {
     return typeId;
   }
 
+  kj::Promise<Result> notSupported() override {
+    KJ_UNIMPLEMENTED("trace event not supported");
+  }
+
 private:
   uint16_t typeId;
   kj::Array<kj::Own<workerd::Trace>> traces;

src/workerd/api/worker-rpc.h

@@ -432,6 +432,10 @@ class JsRpcSessionCustomEventImpl final: public WorkerInterface::CustomEvent {
     return result;
   }
 
+  kj::Promise<Result> notSupported() override {
+    JSG_FAIL_REQUIRE(TypeError, "The receiver is not an RPC object");
+  }
+
   // Event ID for jsRpcSession.
   //
   // Similar to WebSocket hibernation, we define this event ID in the internal codebase, but since

src/workerd/io/worker-interface.h

@@ -118,6 +118,9 @@ class WorkerInterface: public kj::HttpService {
         capnp::ByteStreamFactory& byteStreamFactory,
         rpc::EventDispatcher::Client dispatcher) = 0;
 
+    // The event is not supported by the target, raise an appropriate error.
+    virtual kj::Promise<Result> notSupported() = 0;
+
     // Get the type for this event for logging / metrics purposes. This is intended for use by the
     // RequestObserver. The RequestObserver implementation will define what numbers correspond to
     // what types.

src/workerd/server/server.c++

@@ -560,7 +560,7 @@ private:
     throwUnsupported();
   }
   kj::Promise<CustomEvent::Result> customEvent(kj::Own<CustomEvent> event) override {
-    throwUnsupported();
+    return event->notSupported();
   }
 
   [[noreturn]] void throwUnsupported() {
@@ -875,7 +875,7 @@ private:
     throwUnsupported();
   }
   kj::Promise<CustomEvent::Result> customEvent(kj::Own<CustomEvent> event) override {
-    throwUnsupported();
+    return event->notSupported();
   }
 
   [[noreturn]] void throwUnsupported() {
@@ -1153,7 +1153,7 @@ private:
     throwUnsupported();
   }
   kj::Promise<CustomEvent::Result> customEvent(kj::Own<CustomEvent> event) override {
-    throwUnsupported();
+    return event->notSupported();
   }
 
   [[noreturn]] void throwUnsupported() {