buildx(build): resolveCacheToAttrs func

__tests__/buildx/build.test.ts

@@ -202,6 +202,54 @@ describe('resolveSecret', () => {
   });
 });
 
+describe('resolveCacheToAttrs', () => {
+  // prettier-ignore
+  test.each([
+    [
+      '',
+      undefined,
+      ''
+    ],
+    [
+      'user/app:cache',
+      undefined,
+      'user/app:cache'
+    ],
+    [
+      'type=inline',
+      undefined,
+      'type=inline'
+    ],
+    [
+      'type=gha',
+      undefined,
+      'type=gha,repository=docker/actions-toolkit',
+    ],
+    [
+      'type=gha,mode=max',
+      undefined,
+      'type=gha,mode=max,repository=docker/actions-toolkit',
+    ],
+    [
+      'type=gha,mode=max',
+      'abcd1234',
+      'type=gha,mode=max,repository=docker/actions-toolkit,ghtoken=abcd1234',
+    ],
+    [
+      'type=gha,repository=foo/bar,mode=max',
+      undefined,
+      'type=gha,repository=foo/bar,mode=max',
+    ],
+    [
+      'type=gha,repository=foo/bar,mode=max',
+      'abcd1234',
+      'type=gha,repository=foo/bar,mode=max,ghtoken=abcd1234',
+    ],
+  ])('given %p', async (input: string, githubToken: string | undefined, expected: string) => {
+    expect(Build.resolveCacheToAttrs(input, githubToken)).toEqual(expected);
+  });
+});
+
 describe('hasLocalExporter', () => {
   // prettier-ignore
   test.each([

__tests__/github.test.ts

@@ -32,7 +32,7 @@ jest.spyOn(GitHub.prototype, 'repoData').mockImplementation((): Promise<GitHubRe
 });
 
 describe('repoData', () => {
-  it('returns GitHub repository', async () => {
+  it('returns GitHub repo data', async () => {
     const github = new GitHub();
     expect((await github.repoData()).name).toEqual('Hello-World');
   });
@@ -89,6 +89,12 @@ describe('apiURL', () => {
   });
 });
 
+describe('repository', () => {
+  it('returns GitHub repository', async () => {
+    expect(GitHub.repository).toEqual('docker/actions-toolkit');
+  });
+});
+
 describe('workflowRunURL', () => {
   it('returns 2188748038', async () => {
     expect(GitHub.workflowRunURL).toEqual('https://github.com/docker/actions-toolkit/actions/runs/2188748038/attempts/2');

src/buildx/build.ts

@@ -161,6 +161,45 @@ export class Build {
     return `${input},builder-id=${GitHub.workflowRunURL}`;
   }
 
+  public static resolveCacheToAttrs(input: string, githubToken?: string): string {
+    if (!input) {
+      return input;
+    }
+
+    let cacheType = 'registry';
+    let ghaCacheRepository = '';
+    let ghaCacheGHToken = '';
+
+    const fields = parse(input, {
+      relaxColumnCount: true,
+      skipEmptyLines: true
+    })[0];
+    for (const field of fields) {
+      const parts = field
+        .toString()
+        .split(/(?<=^[^=]+?)=/)
+        .map(item => item.trim());
+      if (parts[0] === 'type') {
+        cacheType = parts[1];
+      } else if (parts[0] === 'repository') {
+        ghaCacheRepository = parts[1];
+      } else if (parts[0] === 'ghtoken') {
+        ghaCacheGHToken = parts[1];
+      }
+    }
+
+    if (cacheType === 'gha') {
+      if (!ghaCacheRepository) {
+        input = `${input},repository=${GitHub.repository}`;
+      }
+      if (!ghaCacheGHToken && githubToken) {
+        input = `${input},ghtoken=${githubToken}`;
+      }
+    }
+
+    return input;
+  }
+
   public static hasLocalExporter(exporters: string[]): boolean {
     return Build.hasExporterType('local', exporters);
   }

src/github.ts

@@ -64,10 +64,14 @@ export class GitHub {
     return process.env.GITHUB_API_URL || 'https://api.github.com';
   }
 
+  static get repository(): string {
+    return `${github.context.repo.owner}/${github.context.repo.repo}`;
+  }
+
   static get workflowRunURL(): string {
     const runID = process.env.GITHUB_RUN_ID || github.context.runId;
     const runAttempt = process.env.GITHUB_RUN_ATTEMPT || 1;
-    return `${GitHub.serverURL}/${github.context.repo.owner}/${github.context.repo.repo}/actions/runs/${runID}/attempts/${runAttempt}`;
+    return `${GitHub.serverURL}/${GitHub.repository}/actions/runs/${runID}/attempts/${runAttempt}`;
   }
 
   static get actionsRuntimeToken(): GitHubActionsRuntimeToken | undefined {