feat(lambda-python): add local bundling option

packages/@aws-cdk/aws-lambda-python-alpha/README.md

@@ -233,6 +233,36 @@ new python.PythonFunction(this, 'function', {
 });
 ```
 
+## Local bundling
+
+Use `local` to specify a local bundling provider. The provider implements a
+method `tryBundle()` which should return `true` if local bundling was performed.
+If `false` is returned, Docker bundling will be done:
+
+ ```ts
+import * as cdk from 'aws-cdk-lib';
+
+class MyBundle implements cdk.ILocalBundling {
+  public tryBundle(outputDir: string, options: cdk.BundlingOptions) {
+    const canRunLocally = true // replace with actual logic
+    if (canRunLocally) {
+      // perform local bundling here
+      return true;
+    }
+    return false;
+  }
+}
+
+const entry = '/path/to/function';
+new python.PythonFunction(this, 'function', {
+  entry,
+  runtime: Runtime.PYTHON_3_8,
+  bundling: {
+    local: new MyBundle()
+  },
+});
+```
+
 ## Command hooks
 
 It is  possible to run additional commands by specifying the `commandHooks` prop:

packages/@aws-cdk/aws-lambda-python-alpha/lib/bundling.ts

@@ -1,6 +1,6 @@
 import * as path from 'path';
 import { Architecture, AssetCode, Code, Runtime } from 'aws-cdk-lib/aws-lambda';
-import { AssetStaging, BundlingFileAccess, BundlingOptions as CdkBundlingOptions, DockerImage, DockerVolume } from 'aws-cdk-lib/core';
+import { AssetStaging, BundlingFileAccess, BundlingOptions as CdkBundlingOptions, DockerImage, DockerVolume, ILocalBundling } from 'aws-cdk-lib/core';
 import { Packaging, DependenciesFile } from './packaging';
 import { BundlingOptions, ICommandHooks } from './types';
 
@@ -73,6 +73,7 @@ export class Bundling implements CdkBundlingOptions {
   public readonly securityOpt?: string;
   public readonly network?: string;
   public readonly bundlingFileAccess?: BundlingFileAccess;
+  public readonly local?: ILocalBundling;
 
   constructor(props: BundlingProps) {
     const {
@@ -114,6 +115,7 @@ export class Bundling implements CdkBundlingOptions {
     this.securityOpt = props.securityOpt;
     this.network = props.network;
     this.bundlingFileAccess = props.bundlingFileAccess;
+    this.local = props.local;
   }
 
   private createBundlingCommand(options: BundlingCommandOptions): string[] {

packages/@aws-cdk/aws-lambda-python-alpha/lib/types.ts

@@ -1,4 +1,4 @@
-import { AssetHashType, BundlingFileAccess, DockerImage, DockerRunOptions } from 'aws-cdk-lib/core';
+import { AssetHashType, BundlingFileAccess, DockerImage, DockerRunOptions, ILocalBundling } from 'aws-cdk-lib/core';
 
 /**
  * Options for bundling
@@ -98,6 +98,17 @@ export interface BundlingOptions extends DockerRunOptions {
    * @default - BundlingFileAccess.BIND_MOUNT
    */
   readonly bundlingFileAccess?: BundlingFileAccess;
+
+  /**
+   * Local bundling provider.
+   *
+   * The provider implements a method `tryBundle()` which should return `true`
+   * if local bundling was performed. If `false` is returned, docker bundling
+   * will be done.
+   *
+   * @default - bundling will only be performed in a Docker container
+   */
+  readonly local?: ILocalBundling;
 }
 
 /**

packages/@aws-cdk/aws-lambda-python-alpha/test/bundling.test.ts

@@ -554,3 +554,25 @@ test('with command hooks', () => {
     }),
   }));
 });
+
+test('Local bundling is used', () => {
+  const entry = path.join(__dirname, 'lambda-handler');
+
+  const local = {
+    tryBundle() {
+      return true;
+    },
+  };
+
+  Bundling.bundle({
+    entry: entry,
+    runtime: Runtime.PYTHON_3_7,
+    local,
+  });
+
+  expect(Code.fromAsset).toHaveBeenCalledWith(entry, expect.objectContaining({
+    bundling: expect.objectContaining({
+      local,
+    }),
+  }));
+});