support custom paths in Git context

README.md

@@ -285,18 +285,18 @@ The following inputs can be used as `step.with` keys:
 >   org.opencontainers.image.vendor=MyCompany
 > ```
 
-| Name              | Type   | Description                                                                  |
-|-------------------|--------|------------------------------------------------------------------------------|
-| `context`         | String | Where to get context data. Allowed options are: `workflow` (default), `git`. |
-| `images`          | List   | List of Docker images to use as base name for tags                           |
-| `tags`            | List   | List of [tags](#tags-input) as key-value pair attributes                     |
-| `flavor`          | List   | [Flavor](#flavor-input) to apply                                             |
-| `labels`          | List   | List of custom labels                                                        |
-| `annotations`     | List   | List of custom annotations                                                   |
-| `sep-tags`        | String | Separator to use for tags output (default `\n`)                              |
-| `sep-labels`      | String | Separator to use for labels output (default `\n`)                            |
-| `sep-annotations` | String | Separator to use for annotations output (default `\n`)                       |
-| `bake-target`     | String | Bake target name (default `docker-metadata-action`)                          |
+| Name              | Type   | Description                                                                                |
+|-------------------|--------|--------------------------------------------------------------------------------------------|
+| `context`         | String | Where to get context data. Allowed options are: `workflow` (default), `git`, `git:<path>`. |
+| `images`          | List   | List of Docker images to use as base name for tags                                         |
+| `tags`            | List   | List of [tags](#tags-input) as key-value pair attributes                                   |
+| `flavor`          | List   | [Flavor](#flavor-input) to apply                                                           |
+| `labels`          | List   | List of custom labels                                                                      |
+| `annotations`     | List   | List of custom annotations                                                                 |
+| `sep-tags`        | String | Separator to use for tags output (default `\n`)                                            |
+| `sep-labels`      | String | Separator to use for labels output (default `\n`)                                          |
+| `sep-annotations` | String | Separator to use for annotations output (default `\n`)                                     |
+| `bake-target`     | String | Bake target name (default `docker-metadata-action`)                                        |
 
 ### outputs
 
@@ -357,6 +357,24 @@ context: git
 * `workflow`: Get context metadata from the workflow (GitHub context). See https://docs.github.com/en/actions/learn-github-actions/contexts#github-context
 * `git`: Get context metadata from the workflow and overrides some of them with current Git context, such as `ref` and `sha`.
 
+Use `context: git:<path>` when the repository is checked out to a custom path.
+The path can be absolute or relative to the current working directory
+(normally `$GITHUB_WORKSPACE`):
+
+```yaml
+- uses: actions/checkout@v7
+  with:
+    path: source
+- uses: docker/metadata-action@v6
+  with:
+    context: git:source
+    images: name/app
+    tags: type=sha
+```
+
+The selected checkout supplies the Git ref, SHA, and commit date. Other repository
+metadata still comes from the workflow repository.
+
 ## `images` input
 
 `images` defines a list of Docker images to use as base name for [`tags`](#tags-input):

__tests__/context.test.ts

@@ -1,8 +1,14 @@
-import {beforeEach, describe, expect, test, it, vi} from 'vitest';
+import {afterEach, beforeEach, describe, expect, test, it, vi} from 'vitest';
+import {execFileSync} from 'child_process';
+import fs from 'fs';
+import path from 'path';
+
 import {Git} from '@docker/actions-toolkit/lib/git.js';
 import {Toolkit} from '@docker/actions-toolkit/lib/toolkit.js';
 
 import * as context from '../src/context.js';
+import {Meta} from '../src/meta.js';
+import repoFixture from './fixtures/repo.json' with {type: 'json'};
 
 const toolkit = new Toolkit({githubToken: 'fake-github-token'});
 
@@ -16,6 +22,11 @@ describe('getInputs', () => {
     }, {});
   });
 
+  it('reads a Git context with a path', () => {
+    setInput('context', 'git:nested checkout');
+    expect(context.getInputs().context).toEqual('git:nested checkout');
+  });
+
   // prettier-ignore
   const cases: [number, Map<string, string>, context.Inputs][] = [
     [
@@ -151,13 +162,26 @@ describe('getInputs', () => {
 });
 
 describe('getContext', () => {
-  it('workflow', async () => {
+  afterEach(() => {
+    vi.restoreAllMocks();
+  });
+
+  it('workflow does not read Git context', async () => {
+    const gitContext = vi.spyOn(Git, 'context');
+    const gitCommitDate = vi.spyOn(Git, 'commitDate');
     const ctx = await context.getContext(context.ContextSource.workflow, toolkit);
     expect(ctx.ref).toEqual('refs/heads/dev');
     expect(ctx.sha).toEqual('5f3331d7f7044c18ca9f12c77d961c4d7cf3276a');
     expect(ctx.commitDate).toEqual(new Date('2024-11-13T13:42:28.000Z'));
+    expect(gitContext).not.toHaveBeenCalled();
+    expect(gitCommitDate).not.toHaveBeenCalled();
   });
-  it('git', async () => {
+  it.each<[string, string | undefined]>([
+    ['git', undefined],
+    ['git:', ''],
+    ['git:source', 'source'],
+    ['git:C:\\nested checkout', 'C:\\nested checkout']
+  ])('reads %s', async (source, workdir) => {
     vi.spyOn(Git, 'context').mockImplementation((): Promise<context.Context> => {
       return Promise.resolve({
         ref: 'refs/heads/git-test',
@@ -167,11 +191,51 @@ describe('getContext', () => {
     vi.spyOn(Git, 'commitDate').mockImplementation(async (): Promise<Date> => {
       return new Date('2023-01-01T13:42:28.000Z');
     });
-    const ctx = await context.getContext(context.ContextSource.git, toolkit);
+    const ctx = await context.getContext(source, toolkit);
+    expect(Git.context).toHaveBeenCalledWith(workdir);
+    expect(Git.commitDate).toHaveBeenCalledWith('git-test-sha', workdir);
     expect(ctx.ref).toEqual('refs/heads/git-test');
     expect(ctx.sha).toEqual('git-test-sha');
     expect(ctx.commitDate).toEqual(new Date('2023-01-01T13:42:28.000Z'));
   });
+
+  it.each(['workflow:source', 'gitfoo:source', 'invalid'])('rejects invalid context %s', async source => {
+    await expect(context.getContext(source, toolkit)).rejects.toThrow(`Invalid context source: ${source}`);
+  });
+
+  it.each(['relative', 'absolute'])('reads a selected checkout using a %s path', async pathType => {
+    const checkoutDir = fs.mkdtempSync(path.join(process.cwd(), 'git context-'));
+    const workdir = pathType === 'relative' ? path.relative(process.cwd(), checkoutDir) : checkoutDir;
+    const commitDate = '2024-01-02T03:04:05Z';
+    const git = (args: string[]) =>
+      execFileSync('git', args, {
+        cwd: checkoutDir,
+        encoding: 'utf8',
+        stdio: 'pipe',
+        env: {...process.env, GIT_AUTHOR_DATE: commitDate, GIT_COMMITTER_DATE: commitDate}
+      }).trim();
+
+    try {
+      git(['init', '--initial-branch=selected-checkout']);
+      git(['-c', 'user.name=Test', '-c', 'user.email=test@example.com', '-c', 'commit.gpgsign=false', 'commit', '--allow-empty', '-m', 'initial']);
+      const sha = git(['rev-parse', 'HEAD']);
+      const ctx = await context.getContext(`git:${workdir}`, toolkit);
+      expect(ctx.ref).toEqual('refs/heads/selected-checkout');
+      expect(ctx.sha).toEqual(sha);
+      expect(ctx.commitDate).toEqual(new Date(commitDate));
+
+      git(['checkout', '--detach', 'HEAD']);
+      git(['branch', '-D', 'selected-checkout']);
+      const detachedContext = await context.getContext(`git:${workdir}`, toolkit);
+      expect(detachedContext.ref).toEqual('');
+      expect(detachedContext.sha).toEqual(sha);
+      expect(detachedContext.commitDate).toEqual(new Date(commitDate));
+      const meta = new Meta({...context.getInputs(), images: ['name/app'], tags: ['type=sha,format=long'], flavor: []}, detachedContext, repoFixture);
+      expect(meta.getTags()).toEqual([`name/app:sha-${sha}`]);
+    } finally {
+      fs.rmSync(checkoutDir, {recursive: true, force: true});
+    }
+  });
 });
 
 // See: https://github.com/actions/toolkit/blob/master/packages/core/src/core.ts#L67

__tests__/fixtures/repo.json

@@ -72,11 +72,14 @@
   "homepage": "https://github.com",
   "language": null,
   "forks_count": 9,
+  "forks": 9,
   "stargazers_count": 80,
   "watchers_count": 80,
+  "watchers": 80,
   "size": 108,
   "default_branch": "master",
   "open_issues_count": 0,
+  "open_issues": 0,
   "is_template": true,
   "topics": [
     "octocat",
@@ -85,6 +88,7 @@
     "api"
   ],
   "has_issues": true,
+  "has_discussions": false,
   "has_projects": true,
   "has_wiki": true,
   "has_pages": false,
@@ -211,11 +215,15 @@
     "homepage": "https://github.com",
     "language": null,
     "forks_count": 9,
+    "forks": 9,
+    "license": null,
     "stargazers_count": 80,
     "watchers_count": 80,
+    "watchers": 80,
     "size": 108,
     "default_branch": "master",
     "open_issues_count": 0,
+    "open_issues": 0,
     "is_template": true,
     "topics": [
       "octocat",
@@ -322,11 +330,15 @@
     "homepage": "https://github.com",
     "language": null,
     "forks_count": 9,
+    "forks": 9,
+    "license": null,
     "stargazers_count": 80,
     "watchers_count": 80,
+    "watchers": 80,
     "size": 108,
     "default_branch": "master",
     "open_issues_count": 0,
+    "open_issues": 0,
     "is_template": true,
     "topics": [
       "octocat",

action.yml

@@ -8,7 +8,7 @@ branding:
 
 inputs:
   context:
-    description: 'Where to get context data. Allowed options are "workflow"  (default), "git".'
+    description: 'Where to get context data. Allowed options are "workflow" (default), "git", "git:<path>".'
     default: "workflow"
     required: true
   images:

src/context.ts

@@ -12,7 +12,7 @@ export interface Context extends GithubContext {
 }
 
 export interface Inputs {
-  context: ContextSource;
+  context: string;
   images: string[];
   tags: string[];
   flavor: string[];
@@ -27,7 +27,7 @@ export interface Inputs {
 
 export function getInputs(): Inputs {
   return {
-    context: (core.getInput('context') || ContextSource.workflow) as ContextSource,
+    context: core.getInput('context') || ContextSource.workflow,
     images: Util.getInputList('images', {ignoreComma: true, comment: '#', commentNoInfix: true}),
     tags: Util.getInputList('tags', {ignoreComma: true, comment: '#', commentNoInfix: true}),
     flavor: Util.getInputList('flavor', {ignoreComma: true, comment: '#', commentNoInfix: true}),
@@ -46,7 +46,10 @@ export enum ContextSource {
   git = 'git'
 }
 
-export async function getContext(source: ContextSource, toolkit: Toolkit): Promise<Context> {
+export async function getContext(source: string, toolkit: Toolkit): Promise<Context> {
+  if (source.startsWith(`${ContextSource.git}:`)) {
+    return await getContextFromGit(source.slice(ContextSource.git.length + 1));
+  }
   switch (source) {
     case ContextSource.workflow:
       return await getContextFromWorkflow(toolkit);
@@ -82,11 +85,11 @@ async function getContextFromWorkflow(toolkit: Toolkit): Promise<Context> {
   } as Context;
 }
 
-async function getContextFromGit(): Promise<Context> {
-  const ctx = await Git.context();
+async function getContextFromGit(workdir?: string): Promise<Context> {
+  const ctx = await Git.context(workdir);
 
   return {
-    commitDate: await Git.commitDate(ctx.sha),
+    commitDate: await Git.commitDate(ctx.sha, workdir),
     ...ctx
   } as Context;
 }