do not build docker image if stack does not require bundling

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

@@ -34,6 +34,13 @@ export interface BundlingProps extends BundlingOptions {
    * @default Architecture.X86_64
    */
   readonly architecture?: Architecture;
+
+  /**
+   * Whether or not the bundling process should be skipped
+   *
+   * @default - Does not skip bundling
+   */
+  readonly skip?: boolean;
 }
 
 /**
@@ -45,7 +52,7 @@ export class Bundling implements CdkBundlingOptions {
       assetHash: options.assetHash,
       assetHashType: options.assetHashType,
       exclude: DEPENDENCY_EXCLUDES,
-      bundling: new Bundling(options),
+      bundling: options.skip ? undefined : new Bundling(options),
     });
   }
 

packages/@aws-cdk/aws-lambda-python/lib/function.ts

@@ -1,6 +1,7 @@
 import * as fs from 'fs';
 import * as path from 'path';
 import { Function, FunctionOptions, Runtime, RuntimeFamily } from '@aws-cdk/aws-lambda';
+import { Stack } from '@aws-cdk/core';
 import { Bundling } from './bundling';
 import { BundlingOptions } from './types';
 
@@ -79,6 +80,7 @@ export class PythonFunction extends Function {
       code: Bundling.bundle({
         entry,
         runtime,
+        skip: !Stack.of(scope).bundlingRequired,
         ...props.bundling,
       }),
       handler: resolvedHandler,

packages/@aws-cdk/aws-lambda-python/lib/layer.ts

@@ -1,5 +1,6 @@
 import * as path from 'path';
 import * as lambda from '@aws-cdk/aws-lambda';
+import { Stack } from '@aws-cdk/core';
 import { Bundling } from './bundling';
 import { BundlingOptions } from './types';
 
@@ -67,6 +68,7 @@ export class PythonLayerVersion extends lambda.LayerVersion {
         runtime,
         architecture,
         outputPathSuffix: 'python',
+        skip: !Stack.of(scope).bundlingRequired,
         ...props.bundling,
       }),
     });

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

@@ -229,3 +229,25 @@ test('Bundling with custom build args', () => {
     }),
   }));
 });
+
+test('Do not build docker image when skipping bundling', () => {
+  const entry = path.join(__dirname, 'lambda-handler');
+  Bundling.bundle({
+    entry: entry,
+    runtime: Runtime.PYTHON_3_7,
+    skip: true,
+  });
+
+  expect(DockerImage.fromBuild).not.toHaveBeenCalled();
+});
+
+test('Build docker image when bundling is not skipped', () => {
+  const entry = path.join(__dirname, 'lambda-handler');
+  Bundling.bundle({
+    entry: entry,
+    runtime: Runtime.PYTHON_3_7,
+    skip: false,
+  });
+
+  expect(DockerImage.fromBuild).toHaveBeenCalled();
+});

packages/@aws-cdk/aws-lambda-python/test/function.test.ts

@@ -167,3 +167,35 @@ test('Allows use of custom bundling image', () => {
     image,
   }));
 });
+
+test('Skip bundling when stack does not require it', () => {
+  const spy = jest.spyOn(stack, 'bundlingRequired', 'get').mockReturnValue(false);
+  const entry = path.join(__dirname, 'lambda-handler');
+
+  new PythonFunction(stack, 'function', {
+    entry,
+    runtime: Runtime.PYTHON_3_8,
+  });
+
+  expect(Bundling.bundle).toHaveBeenCalledWith(expect.objectContaining({
+    skip: true,
+  }));
+
+  spy.mockRestore();
+});
+
+test('Do not skip bundling when stack requires it', () => {
+  const spy = jest.spyOn(stack, 'bundlingRequired', 'get').mockReturnValue(true);
+  const entry = path.join(__dirname, 'lambda-handler');
+
+  new PythonFunction(stack, 'function', {
+    entry,
+    runtime: Runtime.PYTHON_3_8,
+  });
+
+  expect(Bundling.bundle).toHaveBeenCalledWith(expect.objectContaining({
+    skip: false,
+  }));
+
+  spy.mockRestore();
+});

packages/@aws-cdk/aws-lambda-python/test/layer.test.ts

@@ -63,3 +63,33 @@ test('Allows use of custom bundling image', () => {
     image,
   }));
 });
+
+test('Skip bundling when stack does not require it', () => {
+  const spy = jest.spyOn(stack, 'bundlingRequired', 'get').mockReturnValue(false);
+  const entry = path.join(__dirname, 'lambda-handler-project');
+
+  new PythonLayerVersion(stack, 'layer', {
+    entry,
+  });
+
+  expect(Bundling.bundle).toHaveBeenCalledWith(expect.objectContaining({
+    skip: true,
+  }));
+
+  spy.mockRestore();
+});
+
+test('Do not skip bundling when stack requires it', () => {
+  const spy = jest.spyOn(stack, 'bundlingRequired', 'get').mockReturnValue(true);
+  const entry = path.join(__dirname, 'lambda-handler-project');
+
+  new PythonLayerVersion(stack, 'layer', {
+    entry,
+  });
+
+  expect(Bundling.bundle).toHaveBeenCalledWith(expect.objectContaining({
+    skip: false,
+  }));
+
+  spy.mockRestore();
+});