fix(cdk-assets): context path not honored by Docker asset build (#6957)

Prior v1.29.0, the context passed to the docker build command was always
the current working directory. In v1.29.0, this was changed to be the
directory the user passed when instantiating the asset. However, docker
doesn't respect the context passed to the build command when the
`--file` argument is also passed. This broke assets for users passing
the `file` prop when constructing a `DockerImageAsset`.

This is fixed by changing the current working directory of the `docker build`
command and passing that context as `.`. Then docker uses the current working
directory as the context and correctly finds the image definition file from the
`file` prop. An existing integration test in the framework covers this case,
but does not fail unless the stack is deployed fresh since the asset isn't
rebuilt when the hash is not changed.

Fix: #6954 #6814

packages/cdk-assets/lib/private/docker.ts

@@ -37,9 +37,9 @@ export class Docker {
       '--tag', options.tag,
       ...options.target ? ['--target', options.target] : [],
       ...options.file ? ['--file', options.file] : [],
-      options.directory,
+      '.'
     ];
-    await this.execute(buildCommand);
+    await this.execute(buildCommand, { cwd: options.directory });
   }
 
   /**
@@ -100,4 +100,4 @@ async function obtainEcrCredentials(ecr: AWS.ECR, logger?: Logger) {
 
 function flatten(x: string[][]) {
   return Array.prototype.concat([], ...x);
-}
+}

packages/cdk-assets/test/docker-images.test.ts

@@ -7,6 +7,7 @@ import { mockAws, mockedApiFailure, mockedApiResult } from './mock-aws';
 import { mockSpawn } from './mock-child_process';
 
 let aws: ReturnType<typeof mockAws>;
+const absoluteDockerPath = '/simple/cdk.out/dockerdir';
 beforeEach(() => {
   mockfs({
     '/simple/cdk.out/assets.json': JSON.stringify({
@@ -33,7 +34,7 @@ beforeEach(() => {
       dockerImages: {
         theAsset: {
           source: {
-            directory: '/simple/cdk.out/dockerdir'
+            directory: absoluteDockerPath
           },
           destinations: {
             theDestination: {
@@ -112,7 +113,7 @@ describe('with a complete manifest', () => {
     mockSpawn(
       { commandLine: ['docker', 'login', '--username', 'user', '--password-stdin', 'https://proxy.com/'] },
       { commandLine: ['docker', 'inspect', 'cdkasset-theasset'], exitCode: 1 },
-      { commandLine: ['docker', 'build', '--tag', 'cdkasset-theasset', '/simple/cdk.out/dockerdir'] },
+      { commandLine: ['docker', 'build', '--tag', 'cdkasset-theasset', '.'], cwd: absoluteDockerPath },
       { commandLine: ['docker', 'tag', 'cdkasset-theasset', '12345.amazonaws.com/repo:abcdef'] },
       { commandLine: ['docker', 'push', '12345.amazonaws.com/repo:abcdef'] },
     );
@@ -135,7 +136,7 @@ test('correctly identify Docker directory if path is absolute', async () => {
     // Only care about the 'build' command line
     { commandLine: ['docker', 'login'], prefix: true, },
     { commandLine: ['docker', 'inspect'], exitCode: 1, prefix: true },
-    { commandLine: ['docker', 'build', '--tag', 'cdkasset-theasset', '/simple/cdk.out/dockerdir'] },
+    { commandLine: ['docker', 'build', '--tag', 'cdkasset-theasset', '.'], cwd: absoluteDockerPath },
     { commandLine: ['docker', 'tag'], prefix: true },
     { commandLine: ['docker', 'push'], prefix: true },
   );

packages/cdk-assets/test/mock-child_process.ts

@@ -7,6 +7,7 @@ if (!(child_process as any).spawn.mockImplementationOnce) {
 
 export interface Invocation {
   commandLine: string[];
+  cwd?: string;
   exitCode?: number;
   stdout?: string;
 
@@ -20,7 +21,7 @@ export function mockSpawn(...invocations: Invocation[]) {
   let mock = (child_process.spawn as any);
   for (const _invocation of invocations) {
     const invocation = _invocation; // Mirror into variable for closure
-    mock = mock.mockImplementationOnce((binary: string, args: string[], _options: any) => {
+    mock = mock.mockImplementationOnce((binary: string, args: string[], options: child_process.SpawnOptions) => {
       if (invocation.prefix) {
         // Match command line prefix
         expect([binary, ...args].slice(0, invocation.commandLine.length)).toEqual(invocation.commandLine);
@@ -29,6 +30,10 @@ export function mockSpawn(...invocations: Invocation[]) {
         expect([binary, ...args]).toEqual(invocation.commandLine);
       }
 
+      if (invocation.cwd != null) {
+        expect(options.cwd).toBe(invocation.cwd);
+      }
+
       const child: any = new events.EventEmitter();
       child.stdin = new events.EventEmitter();
       child.stdin.write = jest.fn();
@@ -57,4 +62,4 @@ function mockEmit(emitter: events.EventEmitter, event: string, data: any) {
   setImmediate(() => {
     emitter.emit(event, data);
   });
-}
+}