refactor(nexus): extract dispatch logic; simplify operation context handling

Author: xepozz

src/Nexus/Handler/Internal/ServiceHandler.php

@@ -119,29 +119,23 @@ public function startOperation(
             );
         }
 
-        Nexus::setCurrentContext(new NexusContext(
-            operation: self::publicOperationContext($operationContext),
-            workflowClient: $workflowClient,
-            current: $contextWithServiceDefinition,
-            startDetails: $details,
-            outboundPipeline: $this->interceptorProvider
-                ->getPipeline(NexusOperationOutboundCallsInterceptor::class),
-        ));
-        try {
-            $result = $this->interceptorProvider
-                ->getPipeline(NexusOperationInboundCallsInterceptor::class)
-                ->with(
-                    static fn(StartOperationInput $input): OperationStartResult => $handler->start(
-                        $input->operationContext,
-                        $input->startDetails,
-                        $input->input,
-                    ),
-                    /** @see NexusOperationInboundCallsInterceptor::startOperation() */
-                    'startOperation',
-                )(new StartOperationInput($contextWithServiceDefinition, $details, $inputObject));
-        } finally {
-            Nexus::setCurrentContext(null);
-        }
+        $result = $this->dispatch(
+            new NexusContext(
+                operation: self::publicOperationContext($operationContext),
+                workflowClient: $workflowClient,
+                current: $contextWithServiceDefinition,
+                startDetails: $details,
+                outboundPipeline: $this->interceptorProvider
+                    ->getPipeline(NexusOperationOutboundCallsInterceptor::class),
+            ),
+            static fn(StartOperationInput $input): OperationStartResult => $handler->start(
+                $input->operationContext,
+                $input->startDetails,
+                $input->input,
+            ),
+            'startOperation',
+            new StartOperationInput($contextWithServiceDefinition, $details, $inputObject),
+        );
 
         \assert($result instanceof OperationStartResult);
 
@@ -180,27 +174,21 @@ public function cancelOperation(
 
         $contextWithServiceDefinition = $context->withServiceDefinition($instance->prototype);
 
-        Nexus::setCurrentContext(new NexusContext(
-            operation: self::publicOperationContext($operationContext),
-            workflowClient: $workflowClient,
-            current: $contextWithServiceDefinition,
-            cancelDetails: $details,
-            outboundPipeline: $this->interceptorProvider
-                ->getPipeline(NexusOperationOutboundCallsInterceptor::class),
-        ));
-        try {
-            $this->interceptorProvider
-                ->getPipeline(NexusOperationInboundCallsInterceptor::class)
-                ->with(
-                    static function (CancelOperationInput $input) use ($handler): void {
-                        $handler->cancel($input->operationContext, $input->cancelDetails);
-                    },
-                    /** @see NexusOperationInboundCallsInterceptor::cancelOperation() */
-                    'cancelOperation',
-                )(new CancelOperationInput($contextWithServiceDefinition, $details));
-        } finally {
-            Nexus::setCurrentContext(null);
-        }
+        $this->dispatch(
+            new NexusContext(
+                operation: self::publicOperationContext($operationContext),
+                workflowClient: $workflowClient,
+                current: $contextWithServiceDefinition,
+                cancelDetails: $details,
+                outboundPipeline: $this->interceptorProvider
+                    ->getPipeline(NexusOperationOutboundCallsInterceptor::class),
+            ),
+            static function (CancelOperationInput $input) use ($handler): void {
+                $handler->cancel($input->operationContext, $input->cancelDetails);
+            },
+            'cancelOperation',
+            new CancelOperationInput($contextWithServiceDefinition, $details),
+        );
     }
 
     private static function publicOperationContext(NexusOperationContext $operationContext): ?NexusOperationContext
@@ -211,6 +199,21 @@ private static function publicOperationContext(NexusOperationContext $operationC
         return $operationContext;
     }
 
+    /**
+     * @param non-empty-string $method
+     */
+    private function dispatch(NexusContext $dispatchContext, \Closure $terminal, string $method, object $input): mixed
+    {
+        Nexus::setCurrentContext($dispatchContext);
+        try {
+            return $this->interceptorProvider
+                ->getPipeline(NexusOperationInboundCallsInterceptor::class)
+                ->with($terminal, $method)($input);
+        } finally {
+            Nexus::setCurrentContext(null);
+        }
+    }
+
     /**
      * @return array{NexusServiceInstance, OperationHandlerInterface}
      */

src/Nexus/WorkflowRunOperation.php

@@ -59,7 +59,6 @@ public static function start(WorkflowHandle $handle, OperationStartDetails $deta
             $options = $options->withTaskQueue($info->taskQueue);
         }
 
-        // Token = ns+workflowId (stable across retries).
         $token = WorkflowRunOperationToken::generate(
             $info->namespace,
             $options->workflowId,
@@ -90,9 +89,6 @@ public static function start(WorkflowHandle $handle, OperationStartDetails $deta
         $stub = $client->newWorkflowStub($handle->workflowClass, $options);
         $run = $client->start($stub, ...$handle->args);
 
-        // Self-link to WORKFLOW_EXECUTION_STARTED event of the run we just started.
-        // Caller server attaches it to NEXUS_OPERATION_STARTED so UI shows the
-        // caller↔handler chain. Mirror of Java/TS/Python/Go SDK behaviour.
         Nexus::getCurrentOperationContext()->links->add(
             self::buildStartedEventSelfLink($info->namespace, $run->getExecution()),
         );