fix(core): CustomResourceProvider assets are staged in node_modules (#20953)

Instead of using the source code directory as a staging directory (which, from the point of view of the consumer, is inside the `node_modules` directory), create a temporary directory for staging.

Fixes #17460.

----

### All Submissions:

* [x] Have you followed the guidelines in our [Contributing guide?](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md)

### Adding new Unconventional Dependencies:

* [ ] This PR adds new unconventional dependencies following the process described [here](https://github.com/aws/aws-cdk/blob/main/CONTRIBUTING.md/#adding-new-unconventional-dependencies)

### New Features

* [ ] Have you added the new feature to an [integration test](https://github.com/aws/aws-cdk/blob/main/INTEGRATION_TESTS.md)?
	* [ ] Did you use `yarn integ` to deploy the infrastructure and generate the snapshot (i.e. `yarn integ` without `--dry-run`)?

*By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*

Author: otaviomacedo

packages/@aws-cdk/core/lib/custom-resource-provider/custom-resource-provider.ts

@@ -2,10 +2,12 @@ import * as fs from 'fs';
 import * as path from 'path';
 import * as cxapi from '@aws-cdk/cx-api';
 import { Construct } from 'constructs';
+import * as fse from 'fs-extra';
 import { AssetStaging } from '../asset-staging';
 import { FileAssetPackaging } from '../assets';
 import { CfnResource } from '../cfn-resource';
 import { Duration } from '../duration';
+import { FileSystem } from '../fs';
 import { Lazy } from '../lazy';
 import { Size } from '../size';
 import { Stack } from '../stack';
@@ -200,16 +202,17 @@ export class CustomResourceProvider extends Construct {
 
     const stack = Stack.of(scope);
 
-    // copy the entry point to the code directory
-    fs.copyFileSync(ENTRYPOINT_NODEJS_SOURCE, path.join(props.codeDirectory, `${ENTRYPOINT_FILENAME}.js`));
-
     // verify we have an index file there
     if (!fs.existsSync(path.join(props.codeDirectory, 'index.js'))) {
       throw new Error(`cannot find ${props.codeDirectory}/index.js`);
     }
 
+    const stagingDirectory = FileSystem.mkdtemp('cdk-custom-resource');
+    fse.copySync(props.codeDirectory, stagingDirectory);
+    fs.copyFileSync(ENTRYPOINT_NODEJS_SOURCE, path.join(stagingDirectory, `${ENTRYPOINT_FILENAME}.js`));
+
     const staging = new AssetStaging(this, 'Staging', {
-      sourcePath: props.codeDirectory,
+      sourcePath: stagingDirectory,
     });
 
     const assetFileName = staging.relativeStagedPath(stack);

packages/@aws-cdk/core/test/custom-resource-provider/custom-resource-provider.test.ts

@@ -19,18 +19,20 @@ describe('custom resource provider', () => {
     });
 
     // THEN
-    expect(fs.existsSync(path.join(TEST_HANDLER, '__entrypoint__.js'))).toEqual(true);
     const cfn = toCloudFormation(stack);
 
     // The asset hash constantly changes, so in order to not have to chase it, just look
     // it up from the output.
     const staging = stack.node.tryFindChild('Custom:MyResourceTypeCustomResourceProvider')?.node.tryFindChild('Staging') as AssetStaging;
     const assetHash = staging.assetHash;
+    const sourcePath = staging.sourcePath;
     const paramNames = Object.keys(cfn.Parameters);
     const bucketParam = paramNames[0];
     const keyParam = paramNames[1];
     const hashParam = paramNames[2];
 
+    expect(fs.existsSync(path.join(sourcePath, '__entrypoint__.js'))).toEqual(true);
+
     expect(cfn).toEqual({
       Resources: {
         CustomMyResourceTypeCustomResourceProviderRoleBD5E655F: {
@@ -139,9 +141,12 @@ describe('custom resource provider', () => {
     // Then
     const lambda = toCloudFormation(stack).Resources.CustomMyResourceTypeCustomResourceProviderHandler29FBDD2A;
     expect(lambda).toHaveProperty('Metadata');
-    expect(lambda.Metadata).toEqual({
-      'aws:asset:path': `${__dirname}/mock-provider`,
+
+    expect(lambda.Metadata).toMatchObject({
       'aws:asset:property': 'Code',
+
+      // The asset path should be a temporary folder prefixed with 'cdk-custom-resource'
+      'aws:asset:path': expect.stringMatching(/^.*\/cdk-custom-resource\w{6}\/?$/),
     });
 
   });

packages/@aws-cdk/pipelines/test/integ.newpipeline-with-vpc.ts

@@ -51,7 +51,5 @@ const app = new App({
     '@aws-cdk/core:newStyleStackSynthesis': '1',
   },
 });
-new PipelineStack(app, 'PipelineStack', {
-  env: { account: process.env.CDK_DEFAULT_ACCOUNT, region: process.env.CDK_DEFAULT_REGION },
-});
+new PipelineStack(app, 'PipelineStack');
 app.synth();

packages/@aws-cdk/pipelines/test/integ.newpipeline.ts

@@ -56,7 +56,5 @@ const app = new App({
     '@aws-cdk/core:newStyleStackSynthesis': '1',
   },
 });
-new PipelineStack(app, 'PipelineStack', {
-  env: { account: process.env.CDK_DEFAULT_ACCOUNT, region: process.env.CDK_DEFAULT_REGION },
-});
+new PipelineStack(app, 'PipelineStack');
 app.synth();