Fix error forwarding in actions registry to preserve original status codes (#33021)

Signed-off-by: benjdlambert <ben@blam.sh>

packages/backend-defaults/src/alpha/entrypoints/actionsRegistry/DefaultActionsRegistryService.ts

@@ -28,12 +28,7 @@ import {
   ActionsRegistryActionOptions,
   ActionsRegistryService,
 } from '@backstage/backend-plugin-api/alpha';
-import {
-  ForwardedError,
-  InputError,
-  NotAllowedError,
-  NotFoundError,
-} from '@backstage/errors';
+import { InputError, NotAllowedError, NotFoundError } from '@backstage/errors';
 
 export class DefaultActionsRegistryService implements ActionsRegistryService {
   private actions: Map<string, ActionsRegistryActionOptions<any, any>> =
@@ -131,31 +126,24 @@ export class DefaultActionsRegistryService implements ActionsRegistryService {
           );
         }
 
-        try {
-          const result = await action.action({
-            input: input.data,
-            credentials,
-            logger: this.logger,
-          });
+        const result = await action.action({
+          input: input.data,
+          credentials,
+          logger: this.logger,
+        });
 
-          const output = action.schema?.output
-            ? action.schema.output(z).safeParse(result?.output)
-            : ({ success: true, data: result?.output } as const);
+        const output = action.schema?.output
+          ? action.schema.output(z).safeParse(result?.output)
+          : ({ success: true, data: result?.output } as const);
 
-          if (!output.success) {
-            throw new InputError(
-              `Invalid output from action "${req.params.actionId}"`,
-              output.error,
-            );
-          }
-
-          res.json({ output: output.data });
-        } catch (error) {
-          throw new ForwardedError(
-            `Failed execution of action "${req.params.actionId}"`,
-            error,
+        if (!output.success) {
+          throw new InputError(
+            `Invalid output from action "${req.params.actionId}"`,
+            output.error,
           );
         }
+
+        res.json({ output: output.data });
       },
     );
     return router;

packages/backend-defaults/src/alpha/entrypoints/actionsRegistry/actionsRegistryServiceFactory.test.ts

@@ -22,7 +22,7 @@ import {
 import { httpRouterServiceFactory } from '../../../entrypoints/httpRouter';
 import request from 'supertest';
 import { actionsRegistryServiceFactory } from './actionsRegistryServiceFactory';
-import { InputError } from '@backstage/errors';
+import { InputError, NotFoundError } from '@backstage/errors';
 import { actionsRegistryServiceRef } from '@backstage/backend-plugin-api/alpha';
 
 describe('actionsRegistryServiceFactory', () => {
@@ -510,7 +510,7 @@ describe('actionsRegistryServiceFactory', () => {
       expect(body).toMatchObject({ output: { ok: true } });
     });
 
-    it('should return the error from the action if it throws', async () => {
+    it('should forward the original error when the action throws a known error', async () => {
       const { server } = await startTestBackend({
         features: [pluginSubject, ...defaultServices],
       });
@@ -528,9 +528,32 @@ describe('actionsRegistryServiceFactory', () => {
       expect(status).toBe(400);
       expect(body).toMatchObject({
         error: {
-          message: expect.stringContaining(
-            'Failed execution of action "my-plugin:test"',
-          ),
+          name: 'InputError',
+          message: 'test',
+        },
+      });
+    });
+
+    it('should forward a NotFoundError from the action with 404 status', async () => {
+      const { server } = await startTestBackend({
+        features: [pluginSubject, ...defaultServices],
+      });
+
+      mockAction.mockRejectedValue(new NotFoundError('entity not found'));
+
+      const { body, status } = await request(server)
+        .post(
+          '/api/my-plugin/.backstage/actions/v1/actions/my-plugin:test/invoke',
+        )
+        .send({
+          name: 'test',
+        });
+
+      expect(status).toBe(404);
+      expect(body).toMatchObject({
+        error: {
+          name: 'NotFoundError',
+          message: 'entity not found',
         },
       });
     });

packages/backend-test-utils/src/alpha/services/MockActionsRegistry.ts

@@ -17,7 +17,7 @@ import {
   BackstageCredentials,
   LoggerService,
 } from '@backstage/backend-plugin-api';
-import { ForwardedError, InputError, NotFoundError } from '@backstage/errors';
+import { InputError, NotFoundError } from '@backstage/errors';
 import { JsonObject, JsonValue } from '@backstage/types';
 import { z, AnyZodObject } from 'zod';
 import zodToJsonSchema from 'zod-to-json-schema';
@@ -126,31 +126,24 @@ export class MockActionsRegistry
       throw new InputError(`Invalid input to action "${opts.id}"`, input.error);
     }
 
-    try {
-      const result = await action.action({
-        input: input.data,
-        credentials: opts.credentials ?? mockCredentials.none(),
-        logger: this.logger,
-      });
+    const result = await action.action({
+      input: input.data,
+      credentials: opts.credentials ?? mockCredentials.none(),
+      logger: this.logger,
+    });
 
-      const output = action.schema?.output
-        ? action.schema.output(z).safeParse(result?.output)
-        : ({ success: true, data: result?.output } as const);
+    const output = action.schema?.output
+      ? action.schema.output(z).safeParse(result?.output)
+      : ({ success: true, data: result?.output } as const);
 
-      if (!output.success) {
-        throw new InputError(
-          `Invalid output from action "${opts.id}"`,
-          output.error,
-        );
-      }
-
-      return { output: output.data };
-    } catch (error) {
-      throw new ForwardedError(
-        `Failed execution of action "${opts.id}"`,
-        error,
+    if (!output.success) {
+      throw new InputError(
+        `Invalid output from action "${opts.id}"`,
+        output.error,
       );
     }
+
+    return { output: output.data };
   }
 
   register<