chore: support contributing to the AWS CDK using alternative container clients (#23855)

The AWS CDK uses `docker` for a feature subset related to building assets.
For users, we already support the `CDK_DOCKER` env variable to change the container client at runtime.
However contributing to the AWS CDK currently still requires a contributor to have `docker` installed.

This PR extends the support for the `CDK_DOCKER` env variable to contributor tooling.
For example one can now run:

```console
CDK_DOCKER=finch ./scripts/foreach.sh "yarn build"
CDK_DOCKER=finch ./scripts/foreach.sh "yarn test"
```

When using `finch`, the following packages do still fail tests, due to known feature gaps:

```csv
@aws-cdk/aws-ec2
@aws-cdk/aws-lambda
@aws-cdk/aws-lambda-go
@aws-cdk/aws-lambda-python
@aws-cdk/aws-lambda-nodejs
@aws-cdk/aws-s3-deployment
```

---

### All Submissions:

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

### Adding new Construct Runtime Dependencies:

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

packages/@aws-cdk/aws-s3/test/notifications-resource-handler/test.sh

@@ -17,10 +17,11 @@ cp ${script_dir}/test_index.py $PWD
 cp ${script_dir}/Dockerfile $PWD
 
 NOTIFICATIONS_RESOURCE_TEST_NO_DOCKER=${NOTIFICATIONS_RESOURCE_TEST_NO_DOCKER:-""}
+DOCKER_CMD=${CDK_DOCKER:-docker}
 
 if [ -z ${NOTIFICATIONS_RESOURCE_TEST_NO_DOCKER} ]; then
   # this will run our tests inside the right environment
-  docker build .
+  $DOCKER_CMD build .
 else
   python test_index.py
 fi

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

@@ -4,6 +4,8 @@ import * as path from 'path';
 import * as sinon from 'sinon';
 import { DockerImage, FileSystem } from '../lib';
 
+const dockerCmd = process.env.CDK_DOCKER ?? 'docker';
+
 describe('bundling', () => {
   afterEach(() => {
     sinon.restore();
@@ -33,7 +35,7 @@ describe('bundling', () => {
       user: 'user:group',
     });
 
-    expect(spawnSyncStub.calledWith('docker', [
+    expect(spawnSyncStub.calledWith(dockerCmd, [
       'run', '--rm',
       '-u', 'user:group',
       '-v', '/host-path:/container-path:delegated',
@@ -74,13 +76,13 @@ describe('bundling', () => {
     })).digest('hex');
     const tag = `cdk-${tagHash}`;
 
-    expect(spawnSyncStub.firstCall.calledWith('docker', [
+    expect(spawnSyncStub.firstCall.calledWith(dockerCmd, [
       'build', '-t', tag,
       '--build-arg', 'TEST_ARG=cdk-test',
       'docker-path',
     ])).toEqual(true);
 
-    expect(spawnSyncStub.secondCall.calledWith('docker', [
+    expect(spawnSyncStub.secondCall.calledWith(dockerCmd, [
       'run', '--rm',
       tag,
     ])).toEqual(true);
@@ -110,13 +112,13 @@ describe('bundling', () => {
     })).digest('hex');
     const tag = `cdk-${tagHash}`;
 
-    expect(spawnSyncStub.firstCall.calledWith('docker', [
+    expect(spawnSyncStub.firstCall.calledWith(dockerCmd, [
       'build', '-t', tag,
       '--platform', platform,
       'docker-path',
     ])).toEqual(true);
 
-    expect(spawnSyncStub.secondCall.calledWith('docker', [
+    expect(spawnSyncStub.secondCall.calledWith(dockerCmd, [
       'run', '--rm',
       tag,
     ])).toEqual(true);
@@ -146,13 +148,13 @@ describe('bundling', () => {
     })).digest('hex');
     const tag = `cdk-${tagHash}`;
 
-    expect(spawnSyncStub.firstCall.calledWith('docker', [
+    expect(spawnSyncStub.firstCall.calledWith(dockerCmd, [
       'build', '-t', tag,
       '--target', targetStage,
       'docker-path',
     ])).toEqual(true);
 
-    expect(spawnSyncStub.secondCall.calledWith('docker', [
+    expect(spawnSyncStub.secondCall.calledWith(dockerCmd, [
       'run', '--rm',
       tag,
     ])).toEqual(true);
@@ -281,7 +283,7 @@ describe('bundling', () => {
       user: 'user:group',
     });
 
-    expect(spawnSyncStub.calledWith('docker', [
+    expect(spawnSyncStub.calledWith(dockerCmd, [
       'run', '--rm',
       '-u', 'user:group',
       '-v', '/host-path:/container-path:delegated',
@@ -392,7 +394,7 @@ describe('bundling', () => {
       user: 'user:group',
     });
 
-    expect(spawnSyncStub.calledWith('docker', [
+    expect(spawnSyncStub.calledWith(dockerCmd, [
       'run', '--rm',
       '--security-opt', 'no-new-privileges',
       '-u', 'user:group',
@@ -427,7 +429,7 @@ describe('bundling', () => {
       user: 'user:group',
     });
 
-    expect(spawnSyncStub.calledWith('docker', [
+    expect(spawnSyncStub.calledWith(dockerCmd, [
       'run', '--rm',
       '--network', 'host',
       '-u', 'user:group',
@@ -464,7 +466,7 @@ describe('bundling', () => {
       // nevertheless what we want to check here is that the command was built correctly and triggered
     };
 
-    expect(spawnSyncStub.calledWith('docker', [
+    expect(spawnSyncStub.calledWith(dockerCmd, [
       'run', '--rm',
       '-u', 'user:group',
       '--volumes-from', 'foo',
@@ -507,7 +509,7 @@ describe('bundling', () => {
     });
 
     // THEN
-    expect(spawnSyncStub.secondCall.calledWith('docker', [
+    expect(spawnSyncStub.secondCall.calledWith(dockerCmd, [
       'run', '--rm',
       '-u', 'user:group',
       '-v', '/host-path:/container-path:z,delegated',
@@ -548,7 +550,7 @@ describe('bundling', () => {
     });
 
     // THEN
-    expect(spawnSyncStub.secondCall.calledWith('docker', [
+    expect(spawnSyncStub.secondCall.calledWith(dockerCmd, [
       'run', '--rm',
       '-u', 'user:group',
       '-v', '/host-path:/container-path:delegated',
@@ -589,7 +591,7 @@ describe('bundling', () => {
     });
 
     // THEN
-    expect(spawnSyncStub.secondCall.calledWith('docker', [
+    expect(spawnSyncStub.secondCall.calledWith(dockerCmd, [
       'run', '--rm',
       '-u', 'user:group',
       '-v', '/host-path:/container-path:delegated',

packages/@aws-cdk/integ-runner/lib/runner/runner-base.ts

@@ -33,7 +33,7 @@ export interface IntegRunnerOptions {
    *
    * @default - no additional environment variables
    */
-  readonly env?: { [name: string]: string },
+  readonly env?: { [name: string]: string | undefined },
 
   /**
    * tmp cdk.out directory

packages/@aws-cdk/integ-runner/lib/workers/extract/extract_worker.ts

@@ -26,6 +26,7 @@ export function integTestWorker(request: IntegTestBatchRequest): IntegTestWorker
         profile: request.profile,
         env: {
           AWS_REGION: request.region,
+          CDK_DOCKER: process.env.CDK_DOCKER,
         },
         showOutput: verbosity >= 2,
       }, testInfo.destructiveChanges);

packages/cdk-cli-wrapper/lib/cdk-wrapper.ts

@@ -69,6 +69,15 @@ export interface SynthFastOptions {
   readonly env?: { [name: string]: string }
 }
 
+/**
+ * Additional environment variables to set
+ * in the execution environment that will be running
+ * the cdk commands
+ */
+export interface Environment {
+  [key: string]: string | undefined
+}
+
 /**
  * AWS CDK client that provides an API to programatically execute the CDK CLI
  * by wrapping calls to exec the CLI
@@ -86,7 +95,7 @@ export interface CdkCliWrapperOptions {
    *
    * @default - no additional env vars
    */
-  readonly env?: { [key: string]: string },
+  readonly env?: Environment,
 
   /**
    * The path to the cdk executable
@@ -109,7 +118,7 @@ export interface CdkCliWrapperOptions {
  */
 export class CdkCliWrapper implements ICdk {
   private readonly directory: string;
-  private readonly env?: { [key: string]: string };
+  private readonly env?: Environment;
   private readonly cdk: string;
   private readonly showOutput: boolean;
 

scripts/check-build-prerequisites.sh

@@ -74,19 +74,51 @@ else
     wrong_version
 fi
 
+# Container Client
+container_client=${CDK_DOCKER:-docker}
+docker_min="19.03.0"
+finch_min="0.3.0"
+
 # [Docker >= 19.03]
-app="docker"
-app_min="19.03.0"
-check_which $app $app_min
+if [ "$container_client" == "docker" ]; then
+    check_which $container_client $docker_min
 
-# Make sure docker is running
-echo -e "Checking if docker is running... \c"
-docker_running=$(docker ps)
-if [ $? -eq 0 ]
-then
-    echo "Ok"
+    # Make sure docker is running
+    echo -e "Checking if Docker is running... \c"
+    docker_running=$(docker ps)
+    if [ $? -eq 0 ]
+    then
+        echo "Ok"
+    else
+        die "Docker is not running"
+    fi
+
+# [finch >= 0.3.0]
+elif [ "$container_client" == "finch" ]; then
+    check_which $container_client $finch_min
+
+    # Make sure docker is running
+    echo -e "Checking if finch is running... \c"
+    finch_running=$($container_client ps)
+    if [ $? -eq 0 ]
+    then
+        echo "Ok"
+    else
+        die "Finch is not running"
+    fi
 else
-    die "Docker is not running"
+    echo "⚠️ Dependency warning: Unknown container client detected. You have set \"CDK_DOCKER=$CDK_DOCKER\"."
+    check_which $container_client "(unknown version requirement)"
+    echo "While any docker compatible client can be used as a drop-in replacement, support for \"$CDK_DOCKER\" is unknown."
+    echo "Proceed with caution." 
+    echo -e "Checking if $container_client is running... \c"
+    client_running=$($container_client ps)
+    if [ $? -eq 0 ]
+    then
+        echo "Ok"
+    else
+        die "$CDK_DOCKER is not running"
+    fi
 fi
 
 # [.NET == 3.1.x, == 5.x]

tools/@aws-cdk/node-bundle/src/api/bundle.ts

@@ -79,7 +79,7 @@ export interface BundleProps {
    *
    * @default "inline"
    */
-  readonly sourcemap?: 'linked' | 'inline' | 'external' | 'both';  
+  readonly sourcemap?: 'linked' | 'inline' | 'external' | 'both';
 
   /**
    * Minifies the bundled code.