Handle case where synthesis renders empty cdk assembly (#2192)

* Handle case where synthesis renders empty cdk assembly

* fix test

* undo that

* actual fix

Author: sobolk

.changeset/early-pens-eat.md

@@ -0,0 +1,5 @@
+---
+'@aws-amplify/backend-deployer': patch
+---
+
+Handle case where synthesis renders empty cdk assembly

packages/backend-deployer/src/cdk_error_mapper.test.ts

@@ -346,6 +346,20 @@ const testErrorMappings = [
     errorName: 'CloudFormationDeploymentError',
     expectedDownstreamErrorMessage: undefined,
   },
+  {
+    errorMessage: `ENOENT: no such file or directory, open '.amplify/artifacts/cdk.out/manifest.json'`,
+    expectedTopLevelErrorMessage:
+      'The Amplify backend definition is missing `defineBackend` call.',
+    errorName: 'MissingDefineBackendError',
+    expectedDownstreamErrorMessage: undefined,
+  },
+  {
+    errorMessage: `ENOENT: no such file or directory, open '.amplify\\artifacts\\cdk.out\\manifest.json'`,
+    expectedTopLevelErrorMessage:
+      'The Amplify backend definition is missing `defineBackend` call.',
+    errorName: 'MissingDefineBackendError',
+    expectedDownstreamErrorMessage: undefined,
+  },
 ];
 
 void describe('invokeCDKCommand', { concurrency: 1 }, () => {

packages/backend-deployer/src/cdk_error_mapper.ts

@@ -263,6 +263,20 @@ export class CdkErrorMapper {
       errorName: 'BackendSynthError',
       classification: 'ERROR',
     },
+    {
+      // This happens when 'defineBackend' call is missing in customer's app.
+      // 'defineBackend' creates CDK app in memory. If it's missing then no cdk.App exists in memory and nothing is rendered.
+      // During 'cdk synth' CDK CLI attempts to read CDK assembly after calling customer's app.
+      // But no files are rendered causing it to fail.
+      errorRegex:
+        /ENOENT: no such file or directory, open '\.amplify.artifacts.cdk\.out.manifest\.json'/,
+      humanReadableErrorMessage:
+        'The Amplify backend definition is missing `defineBackend` call.',
+      resolutionMessage:
+        'Check your backend definition in the `amplify` folder. Ensure that `amplify/backend.ts` contains `defineBackend` call.',
+      errorName: 'MissingDefineBackendError',
+      classification: 'ERROR',
+    },
     {
       // "Catch all": the backend entry point file is referenced in the stack indicating a problem in customer code
       errorRegex: /amplify\/backend/,
@@ -317,11 +331,11 @@ export type CDKDeploymentError =
   | 'CFNUpdateNotSupportedError'
   | 'CloudFormationDeploymentError'
   | 'FilePermissionsError'
+  | 'MissingDefineBackendError'
   | 'MultipleSandboxInstancesError'
   | 'ESBuildError'
   | 'ExpiredTokenError'
   | 'FileConventionError'
-  | 'FileConventionError'
   | 'ModuleNotFoundError'
   | 'SecretNotSetError'
   | 'SyntaxError';