feat: add variable commit_date

Signed-off-by: Trim21 <trim21.me@gmail.com>

src/context.ts

@@ -1,8 +1,13 @@
 import * as core from '@actions/core';
-import {Context} from '@actions/github/lib/context';
+import {Context as GithubContext} from '@actions/github/lib/context';
 import {Util} from '@docker/actions-toolkit/lib/util';
 import {Git} from '@docker/actions-toolkit/lib/git';
 import {GitHub} from '@docker/actions-toolkit/lib/github';
+import {Toolkit} from '@docker/actions-toolkit/lib/toolkit';
+
+export interface Context extends GithubContext {
+  commitDate: Date;
+}
 
 export interface Inputs {
   context: ContextSource;
@@ -39,10 +44,10 @@ export enum ContextSource {
   git = 'git'
 }
 
-export async function getContext(source: ContextSource): Promise<Context> {
+export async function getContext(source: ContextSource, toolkit: Toolkit): Promise<Context> {
   switch (source) {
     case ContextSource.workflow:
-      return getContextFromWorkflow();
+      return await getContextFromWorkflow(toolkit);
     case ContextSource.git:
       return await getContextFromGit();
     default:
@@ -50,7 +55,7 @@ export async function getContext(source: ContextSource): Promise<Context> {
   }
 }
 
-function getContextFromWorkflow(): Context {
+async function getContextFromWorkflow(toolkit: Toolkit): Promise<Context> {
   const context = GitHub.context;
 
   // Needs to override Git reference with pr ref instead of upstream branch ref
@@ -69,9 +74,56 @@ function getContextFromWorkflow(): Context {
     }
   }
 
-  return context;
+  return {
+    commitDate: await getCommitDateFromWorkflow(context.sha, toolkit),
+    ...context
+  } as Context;
 }
 
 async function getContextFromGit(): Promise<Context> {
-  return await Git.context();
+  const ctx = await Git.context();
+
+  return {
+    commitDate: await Git.commitDate(ctx.sha),
+    ...ctx
+  } as Context;
+}
+
+async function getCommitDateFromWorkflow(sha: string, toolkit: Toolkit): Promise<Date> {
+  const event = GitHub.context.payload as unknown as {
+    // branch push
+    commits?: Array<{
+      timestamp: string;
+      // commit sha
+      id: string;
+    }>;
+    // tags
+    head_commit?: {
+      timestamp: string;
+      // commit sha
+      id: string;
+    };
+  };
+
+  if (event.commits) {
+    const commitDate = event.commits.find(x => x.id === sha)?.timestamp;
+    if (commitDate) {
+      return new Date(commitDate);
+    }
+  }
+
+  if (event.head_commit) {
+    if (event.head_commit.id === sha) {
+      return new Date(event.head_commit.timestamp);
+    }
+  }
+
+  // fallback to github api for commit date
+  const commit = await toolkit.github.octokit.request('GET /repos/{owner}/{repo}/commits/{commit_sha}', {
+    commit_sha: sha,
+    owner: GitHub.context.repo.owner,
+    repo: GitHub.context.repo.repo
+  });
+
+  return new Date(commit.data.committer.date);
 }

src/main.ts

@@ -11,7 +11,7 @@ actionsToolkit.run(
   async () => {
     const inputs: Inputs = getInputs();
     const toolkit = new Toolkit({githubToken: inputs.githubToken});
-    const context = await getContext(inputs.context);
+    const context = await getContext(inputs.context, toolkit);
     const repo = await toolkit.github.repoData();
 
     await core.group(`Context info`, async () => {
@@ -23,6 +23,7 @@ actionsToolkit.run(
       core.info(`actor: ${context.actor}`);
       core.info(`runNumber: ${context.runNumber}`);
       core.info(`runId: ${context.runId}`);
+      core.info(`commitDate: ${context.commitDate}`);
     });
 
     if (core.isDebug()) {

src/meta.ts

@@ -5,11 +5,10 @@ import moment from 'moment-timezone';
 import * as pep440 from '@renovate/pep440';
 import * as semver from 'semver';
 import * as core from '@actions/core';
-import {Context} from '@actions/github/lib/context';
 import {Context as ToolkitContext} from '@docker/actions-toolkit/lib/context';
 import {GitHubRepo} from '@docker/actions-toolkit/lib/types/github';
 
-import {Inputs} from './context';
+import {Inputs, Context} from './context';
 import * as icl from './image';
 import * as tcl from './tag';
 import * as fcl from './flavor';
@@ -115,6 +114,7 @@ export class Meta {
     }
 
     const currentDate = this.date;
+    const commitDate = this.context.commitDate;
     const vraw = this.setValue(
       handlebars.compile(tag.attrs['pattern'])({
         date: function (format, options) {
@@ -130,6 +130,20 @@ export class Meta {
             }
           });
           return m.tz(tz).format(format);
+        },
+        commit_date: function (format, options) {
+          const m = moment(commitDate);
+          let tz = 'UTC';
+          Object.keys(options.hash).forEach(key => {
+            switch (key) {
+              case 'tz':
+                tz = options.hash[key];
+                break;
+              default:
+                throw new Error(`Unknown ${key} attribute`);
+            }
+          });
+          return m.tz(tz).format(format);
         }
       }),
       tag
@@ -361,6 +375,7 @@ export class Meta {
   private setGlobalExp(val): string {
     const context = this.context;
     const currentDate = this.date;
+    const commitDate = this.context.commitDate;
     return handlebars.compile(val)({
       branch: function () {
         if (!/^refs\/heads\//.test(context.ref)) {
@@ -388,6 +403,20 @@ export class Meta {
         }
         return '';
       },
+      commit_date: function (format, options) {
+        const m = moment(commitDate);
+        let tz = 'UTC';
+        Object.keys(options.hash).forEach(key => {
+          switch (key) {
+            case 'tz':
+              tz = options.hash[key];
+              break;
+            default:
+              throw new Error(`Unknown ${key} attribute`);
+          }
+        });
+        return m.tz(tz).format(format);
+      },
       is_default_branch: function () {
         const branch = context.ref.replace(/^refs\/heads\//g, '');
         // TODO: "base_ref" is available in the push payload but doesn't always seem to