store server_action_form_data in flattened form

Author: mydea

dev-packages/e2e-tests/test-applications/nextjs-app-dir/tests/transactions.test.ts

@@ -130,9 +130,9 @@ test('Should send a transaction for instrumented server actions', async ({ page
   await page.getByText('Run Action').click();
 
   expect(await serverComponentTransactionPromise).toBeDefined();
-  expect((await serverComponentTransactionPromise).contexts?.trace?.data?.['server_action_form_data']).toEqual(
-    expect.objectContaining({ 'some-text-value': 'some-default-value' }),
-  );
+  expect(
+    (await serverComponentTransactionPromise).contexts?.trace?.data?.['server_action_form_data.some-text-value'],
+  ).toEqual('some-default-value');
   expect((await serverComponentTransactionPromise).contexts?.trace?.data?.['server_action_result']).toEqual({
     city: 'Vienna',
   });

packages/nextjs/src/common/withServerActionInstrumentation.ts

@@ -6,7 +6,6 @@ import {
   handleCallbackErrors,
   runWithAsyncContext,
   startSpan,
-  withScope,
 } from '@sentry/core';
 import { logger, tracingContextFromHeaders } from '@sentry/utils';
 
@@ -85,48 +84,41 @@ async function withServerActionInstrumentationImplementation<A extends (...args:
 
     let res;
     try {
-      res = await withScope(scope => {
-        if (options.formData) {
-          const formDataObject: Record<string, unknown> = {};
-          options.formData.forEach((value, key) => {
-            if (typeof value === 'string') {
-              formDataObject[key] = value;
-            } else {
-              formDataObject[key] = '[non-string value]';
-            }
-          });
-          // Since formDataObject is not a primitive, we cannot store it on the span as attributes
-          // so instead we put it as extra on the scope
-          scope.setExtra('server_action_form_data', formDataObject);
-        }
-
-        return startSpan(
-          {
-            op: 'function.server_action',
-            name: `serverAction/${serverActionName}`,
-            status: 'ok',
-            ...traceparentData,
-            metadata: {
-              source: 'route',
-              dynamicSamplingContext: traceparentData && !dynamicSamplingContext ? {} : dynamicSamplingContext,
-              request: {
-                headers: fullHeadersObject,
-              },
+      res = startSpan(
+        {
+          op: 'function.server_action',
+          name: `serverAction/${serverActionName}`,
+          status: 'ok',
+          ...traceparentData,
+          metadata: {
+            source: 'route',
+            dynamicSamplingContext: traceparentData && !dynamicSamplingContext ? {} : dynamicSamplingContext,
+            request: {
+              headers: fullHeadersObject,
             },
           },
-          async span => {
-            const result = await handleCallbackErrors(callback, error => {
-              captureException(error, { mechanism: { handled: false } });
-            });
+        },
+        async span => {
+          const result = await handleCallbackErrors(callback, error => {
+            captureException(error, { mechanism: { handled: false } });
+          });
 
-            if (options.recordResponse !== undefined ? options.recordResponse : sendDefaultPii) {
-              span?.setAttribute('server_action_result', result);
-            }
+          if (options.recordResponse !== undefined ? options.recordResponse : sendDefaultPii) {
+            span?.setAttribute('server_action_result', result);
+          }
 
-            return result;
-          },
-        );
-      });
+          if (options.formData) {
+            options.formData.forEach((value, key) => {
+              span?.setAttribute(
+                `server_action_form_data.${key}`,
+                typeof value === 'string' ? value : '[non-string value]',
+              );
+            });
+          }
+
+          return result;
+        },
+      );
     } finally {
       if (!platformSupportsStreaming()) {
         // Lambdas require manual flushing to prevent execution freeze before the event is sent