feat(cli): skip bundling for operations where stack is not needed

packages/@aws-cdk/core/lib/asset-staging.ts

@@ -7,6 +7,7 @@ import { AssetHashType, AssetOptions } from './assets';
 import { BundlingOptions } from './bundling';
 import { Construct } from './construct-compat';
 import { FileSystem, FingerprintOptions } from './fs';
+import { Stack } from './stack';
 import { Stage } from './stage';
 
 /**
@@ -97,16 +98,26 @@ export class AssetStaging extends Construct {
     const hashType = determineHashType(props.assetHashType, props.assetHash);
 
     if (props.bundling) {
-      // Determine the source hash in advance of bundling if the asset hash type
-      // is SOURCE so that the bundler can opt to re-use its previous output.
-      const sourceHash = hashType === AssetHashType.SOURCE
-        ? this.calculateHash(hashType, props.assetHash, props.bundling)
-        : undefined;
-
-      this.bundleDir = this.bundle(props.bundling, outdir, sourceHash);
-      this.assetHash = sourceHash ?? this.calculateHash(hashType, props.assetHash, props.bundling);
-      this.relativePath = renderAssetFilename(this.assetHash);
-      this.stagedPath = this.relativePath;
+      // Check if we actually have to bundle for this stack
+      const bundlingStacks: string[] = this.node.tryGetContext(cxapi.BUNDLING_STACKS) ?? ['*'];
+      const runBundling = bundlingStacks.includes(Stack.of(this).stackName) || bundlingStacks.includes('*');
+      if (runBundling) {
+        // Determine the source hash in advance of bundling if the asset hash type
+        // is SOURCE so that the bundler can opt to re-use its previous output.
+        const sourceHash = hashType === AssetHashType.SOURCE
+          ? this.calculateHash(hashType, props.assetHash, props.bundling)
+          : undefined;
+
+        this.bundleDir = this.bundle(props.bundling, outdir, sourceHash);
+        this.assetHash = sourceHash ?? this.calculateHash(hashType, props.assetHash, props.bundling);
+        this.relativePath = renderAssetFilename(this.assetHash);
+        this.stagedPath = this.relativePath;
+      } else { // Bundling is skipped
+        this.assetHash = props.assetHashType === AssetHashType.BUNDLE
+          ? this.calculateHash(AssetHashType.CUSTOM, this.node.path) // Use node path as dummy hash because we're not bundling
+          : this.calculateHash(hashType, props.assetHash);
+        this.stagedPath = this.sourcePath;
+      }
     } else {
       this.assetHash = this.calculateHash(hashType, props.assetHash);
 

packages/@aws-cdk/core/test/test.staging.ts

@@ -580,6 +580,31 @@ export = {
 
     test.done();
   },
+
+  'bundling looks at bundling stacks in context'(test: Test) {
+    // GIVEN
+    const app = new App();
+    const stack = new Stack(app, 'MyStack');
+    stack.node.setContext(cxapi.BUNDLING_STACKS, ['OtherStack']);
+    const directory = path.join(__dirname, 'fs', 'fixtures', 'test1');
+
+    // WHEN
+    const asset = new AssetStaging(stack, 'Asset', {
+      sourcePath: directory,
+      assetHashType: AssetHashType.BUNDLE,
+      bundling: {
+        image: BundlingDockerImage.fromRegistry('alpine'),
+        command: [DockerStubCommand.SUCCESS],
+      },
+    });
+
+    test.throws(() => readDockerStubInput()); // Bundling did not run
+    test.equal(asset.assetHash, '3d96e735e26b857743a7c44523c9160c285c2d3ccf273d80fa38a1e674c32cb3'); // hash of MyStack/Asset
+    test.equal(asset.sourcePath, directory);
+    test.equal(stack.resolve(asset.stagedPath), directory);
+
+    test.done();
+  },
 };
 
 // Reads a docker stub and cleans the volume paths out of the stub.

packages/@aws-cdk/cx-api/lib/app.ts

@@ -27,3 +27,8 @@ export const DISABLE_ASSET_STAGING_CONTEXT = 'aws:cdk:disable-asset-staging';
  * Omits stack traces from construct metadata entries.
  */
 export const DISABLE_METADATA_STACK_TRACE = 'aws:cdk:disable-stack-trace';
+
+/**
+ * Run bundling for stacks specified in this context key
+ */
+export const BUNDLING_STACKS = 'aws:cdk:bundling-stacks';

packages/aws-cdk/README.md

@@ -307,6 +307,11 @@ $ cdk doctor
   - AWS_SDK_LOAD_CONFIG = 1
 ```
 
+#### Bundling
+By default asset bundling is skipped for `cdk list` and `cdk destroy`. For `cdk deploy`, `cdk diff`
+and `cdk synthesize` the default is to bundle assets for all stacks unless `exclusively` is specified.
+In this case, only the listed stacks will have their assets bundled.
+
 ### MFA support
 
 If `mfa_serial` is found in the active profile of the shared ini file AWS CDK

packages/aws-cdk/bin/cdk.ts

@@ -17,7 +17,7 @@ import { availableInitLanguages, cliInit, printAvailableTemplates } from '../lib
 import { data, debug, error, print, setLogLevel } from '../lib/logging';
 import { PluginHost } from '../lib/plugin';
 import { serializeStructure } from '../lib/serialize';
-import { Configuration, Settings } from '../lib/settings';
+import { Command, Configuration, Settings } from '../lib/settings';
 import * as version from '../lib/version';
 
 /* eslint-disable max-len */
@@ -136,7 +136,10 @@ async function initCommandLine() {
   debug('CDK toolkit version:', version.DISPLAY_VERSION);
   debug('Command line arguments:', argv);
 
-  const configuration = new Configuration(argv);
+  const configuration = new Configuration({
+    ...argv,
+    _: argv._ as [Command, ...string[]], // TypeScript at its best
+  });
   await configuration.load();
 
   const sdkProvider = await SdkProvider.withAwsCliCompatibleDefaults({

packages/aws-cdk/lib/api/cxapp/exec.ts

@@ -39,6 +39,9 @@ export async function execProgram(aws: SdkProvider, config: Configuration): Prom
     context[cxapi.DISABLE_ASSET_STAGING_CONTEXT] = true;
   }
 
+  const bundlingStacks = config.settings.get(['bundlingStacks']) ?? ['*'];
+  context[cxapi.BUNDLING_STACKS] = bundlingStacks;
+
   debug('context:', context);
   env[cxapi.CONTEXT_ENV] = JSON.stringify(context);
 

packages/aws-cdk/lib/settings.ts

@@ -18,7 +18,33 @@ export const TRANSIENT_CONTEXT_KEY = '$dontSaveContext';
 
 const CONTEXT_KEY = 'context';
 
-export type Arguments = { readonly [name: string]: unknown };
+export enum Command {
+  LS = 'ls',
+  LIST = 'list',
+  DIFF = 'diff',
+  BOOTSTRAP = 'bootstrap',
+  DEPLOY = 'deploy',
+  DESTROY = 'destroy',
+  SYNTHESIZE = 'synthesize',
+  SYNTH = 'synth',
+  METADATA = 'metadata',
+  INIT = 'init',
+  VERSION = 'version',
+}
+
+const BUNDLING_COMMANDS = [
+  Command.DEPLOY,
+  Command.DIFF,
+  Command.SYNTH,
+  Command.SYNTHESIZE,
+];
+
+export type Arguments = {
+  readonly _: [Command, ...string[]];
+  readonly exclusively?: boolean;
+  readonly STACKS?: string[];
+  readonly [name: string]: unknown;
+};
 
 /**
  * All sources of settings combined
@@ -185,6 +211,18 @@ export class Settings {
     const context = this.parseStringContextListToObject(argv);
     const tags = this.parseStringTagsListToObject(expectStringList(argv.tags));
 
+    // Determine bundling stacks
+    let bundlingStacks: string[];
+    if (BUNDLING_COMMANDS.includes(argv._[0])) {
+    // If we deploy, diff or synth a list of stacks exclusively we skip
+    // bundling for all other stacks.
+      bundlingStacks = argv.exclusively
+        ? argv.STACKS ?? ['*']
+        : ['*'];
+    } else { // Skip bundling for all stacks
+      bundlingStacks = [];
+    }
+
     return new Settings({
       app: argv.app,
       browser: argv.browser,
@@ -205,6 +243,7 @@ export class Settings {
       staging: argv.staging,
       output: argv.output,
       progress: argv.progress,
+      bundlingStacks,
     });
   }
 
@@ -396,4 +435,4 @@ function expectStringList(x: unknown): string[] | undefined {
     throw new Error(`Expected list of strings, found ${nonStrings}`);
   }
   return x;
-}
+}

packages/aws-cdk/test/context.test.ts

@@ -100,7 +100,7 @@ test('surive no context in old file', async () => {
 test('command line context is merged with stored context', async () => {
   // GIVEN
   await fs.writeJSON('cdk.context.json', { boo: 'far' });
-  const config = await new Configuration({ context: ['foo=bar'] } as any).load();
+  const config = await new Configuration({ context: ['foo=bar'], _: ['command'] } as any).load();
 
   // WHEN
   expect(config.context.all).toEqual({ foo: 'bar', boo: 'far' });

packages/aws-cdk/test/settings.test.ts

@@ -1,4 +1,4 @@
-import { Context, Settings } from '../lib/settings';
+import { Command, Context, Settings } from '../lib/settings';
 
 test('can delete values from Context object', () => {
   // GIVEN
@@ -62,8 +62,8 @@ test('can clear all values in all objects', () => {
 
 test('can parse string context from command line arguments', () => {
   // GIVEN
-  const settings1 = Settings.fromCommandLineArguments({ context: ['foo=bar'] });
-  const settings2 = Settings.fromCommandLineArguments({ context: ['foo='] });
+  const settings1 = Settings.fromCommandLineArguments({ context: ['foo=bar'], _: [Command.DEPLOY] });
+  const settings2 = Settings.fromCommandLineArguments({ context: ['foo='], _: [Command.DEPLOY] });
 
   // THEN
   expect(settings1.get(['context']).foo).toEqual( 'bar');
@@ -72,10 +72,42 @@ test('can parse string context from command line arguments', () => {
 
 test('can parse string context from command line arguments with equals sign in value', () => {
   // GIVEN
-  const settings1 = Settings.fromCommandLineArguments({ context: ['foo==bar='] });
-  const settings2 = Settings.fromCommandLineArguments({ context: ['foo=bar='] });
+  const settings1 = Settings.fromCommandLineArguments({ context: ['foo==bar='], _: [Command.DEPLOY] });
+  const settings2 = Settings.fromCommandLineArguments({ context: ['foo=bar='], _: [Command.DEPLOY] });
 
   // THEN
   expect(settings1.get(['context']).foo).toEqual( '=bar=');
   expect(settings2.get(['context']).foo).toEqual( 'bar=');
 });
+
+test('bundling stacks defaults to an empty list', () => {
+  // GIVEN
+  const settings = Settings.fromCommandLineArguments({
+    _: [Command.LIST],
+  });
+
+  // THEN
+  expect(settings.get(['bundlingStacks'])).toEqual([]);
+});
+
+test('bundling stacks defaults to * for deploy', () => {
+  // GIVEN
+  const settings = Settings.fromCommandLineArguments({
+    _: [Command.DEPLOY],
+  });
+
+  // THEN
+  expect(settings.get(['bundlingStacks'])).toEqual(['*']);
+});
+
+test('bundling stacks with deploy exclusively', () => {
+  // GIVEN
+  const settings = Settings.fromCommandLineArguments({
+    _: [Command.DEPLOY],
+    exclusively: true,
+    STACKS: ['cool-stack'],
+  });
+
+  // THEN
+  expect(settings.get(['bundlingStacks'])).toEqual(['cool-stack']);
+});