feat(lambda-nodejs): support esbuild inject (#19221)

Closes #19133 ---- *By submitting this pull request, I confirm that my contribution is made under the terms of the Apache-2.0 license*
aws · Mar 4, 2022 · 3432c45 · 3432c45
1 parent 5dc61ea
commit 3432c45
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diff --git a/packages/@aws-cdk/aws-lambda-nodejs/README.md b/packages/@aws-cdk/aws-lambda-nodejs/README.md
@@ -198,6 +198,7 @@ new lambda.NodejsFunction(this, 'my-handler', {
     charset: lambda.Charset.UTF8, // do not escape non-ASCII characters, defaults to Charset.ASCII
     format: lambda.OutputFormat.ESM, // ECMAScript module output format, defaults to OutputFormat.CJS (OutputFormat.ESM requires Node.js 14.x)
     mainFields: ['module', 'main'], // prefer ECMAScript versions of dependencies
+    inject: ['./my-shim.js', './other-shim.js'] // allows to automatically replace a global variable with an import from another file
   },
 });
 ```

diff --git a/packages/@aws-cdk/aws-lambda-nodejs/lib/bundling.ts b/packages/@aws-cdk/aws-lambda-nodejs/lib/bundling.ts
@@ -198,6 +198,7 @@ export class Bundling implements cdk.BundlingOptions {
       ...this.props.footer ? [`--footer:js=${JSON.stringify(this.props.footer)}`] : [],
       ...this.props.charset ? [`--charset=${this.props.charset}`] : [],
       ...this.props.mainFields ? [`--main-fields=${this.props.mainFields.join(',')}`] : [],
+      ...this.props.inject ? this.props.inject.map(i => `--inject:${i}`) : [],
     ];
 
     let depsCommand = '';

diff --git a/packages/@aws-cdk/aws-lambda-nodejs/lib/types.ts b/packages/@aws-cdk/aws-lambda-nodejs/lib/types.ts
@@ -279,6 +279,15 @@ export interface BundlingOptions {
    * @default ['main', 'module']
    */
   readonly mainFields?: string[];
+
+  /**
+   * This option allows you to automatically replace a global variable with an
+   * import from another file.
+   *
+   * @see https://esbuild.github.io/api/#inject
+   * @default - no code is injected
+   */
+  readonly inject?: string[]
 }
 
 /**

diff --git a/packages/@aws-cdk/aws-lambda-nodejs/test/bundling.test.ts b/packages/@aws-cdk/aws-lambda-nodejs/test/bundling.test.ts
@@ -208,6 +208,7 @@ test('esbuild bundling with esbuild options', () => {
       'process.env.STRING': JSON.stringify('this is a "test"'),
     },
     format: OutputFormat.ESM,
+    inject: ['./my-shim.js'],
   });
 
   // Correctly bundles with esbuild
@@ -224,7 +225,7 @@ test('esbuild bundling with esbuild options', () => {
           defineInstructions,
           '--log-level=silent --keep-names --tsconfig=/asset-input/lib/custom-tsconfig.ts',
           '--metafile=/asset-output/index.meta.json --banner:js="/* comments */" --footer:js="/* comments */"',
-          '--charset=utf8 --main-fields=module,main',
+          '--charset=utf8 --main-fields=module,main --inject:./my-shim.js',
         ].join(' '),
       ],
     }),