Enable supplying a commit message template

action.yml

@@ -9,6 +9,12 @@ inputs:
     description: "GITHUB_TOKEN or a `repo` scoped Personal Access Token (PAT)"
     required: false
     default: ${{ github.token }}
+  commit-msg-template:
+    description: |
+      The commit message template to use. Variable: `flake_input`.
+    required: false
+    default: |
+      flake.lock: Updated {{ flake_input }}
   commit-msg:
     description: "The message provided with the commit"
     required: false

package.json

@@ -29,7 +29,8 @@
   "dependencies": {
     "@actions/core": "^1.10.1",
     "@actions/exec": "^1.1.1",
-    "detsys-ts": "github:DeterminateSystems/detsys-ts"
+    "detsys-ts": "github:DeterminateSystems/detsys-ts",
+    "handlebars": "^4.7.8"
   },
   "devDependencies": {
     "@trivago/prettier-plugin-sort-imports": "^4.3.0",

pnpm-lock.yaml

@@ -14,6 +14,9 @@ dependencies:
   detsys-ts:
     specifier: github:DeterminateSystems/detsys-ts
     version: github.com/DeterminateSystems/detsys-ts/fe64ba33b4bdeec0991bb65ae00420bf68b9954c
+  handlebars:
+    specifier: ^4.7.8
+    version: 4.7.8
 
 devDependencies:
   '@trivago/prettier-plugin-sort-imports':
@@ -2680,6 +2683,19 @@ packages:
     resolution: {integrity: sha512-EtKwoO6kxCL9WO5xipiHTZlSzBm7WLT627TqC/uVRd0HKmq8NXyebnNYxDoBi7wt8eTWrUrKXCOVaFq9x1kgag==}
     dev: true
 
+  /handlebars@4.7.8:
+    resolution: {integrity: sha512-vafaFqs8MZkRrSX7sFVUdo3ap/eNiLnb4IakshzvP56X5Nr1iGKAIqdX6tMlm6HcNRIkr6AxO5jFEoJzzpT8aQ==}
+    engines: {node: '>=0.4.7'}
+    hasBin: true
+    dependencies:
+      minimist: 1.2.8
+      neo-async: 2.6.2
+      source-map: 0.6.1
+      wordwrap: 1.0.0
+    optionalDependencies:
+      uglify-js: 3.17.4
+    dev: false
+
   /has-bigints@1.0.2:
     resolution: {integrity: sha512-tSvCKtBr9lkF0Ex0aQiP9N+OpV4zi2r/Nee5VkRDbaqv35RLYMzbwQfFSZZH0kR+Rd6302UJZ2p/bJCEoR3VoQ==}
     dev: true
@@ -3229,7 +3245,6 @@ packages:
 
   /minimist@1.2.8:
     resolution: {integrity: sha512-2yyAR8qBkN3YuheJanUpWC5U3bb5osDywNB8RzDVlDwDHbocAJveqqj1u8+SVD7jkWT4yvsHCpWqqWqAxb0zCA==}
-    dev: true
 
   /minipass@7.1.2:
     resolution: {integrity: sha512-qOOzS1cBTWYF4BH8fVePDBOO9iptMnGUEZwNc/cMWnTV2nVLZ7VoNWEPHkYczZA0pdoA7dl6e7FL659nX9S2aw==}
@@ -3271,6 +3286,10 @@ packages:
     resolution: {integrity: sha512-OWND8ei3VtNC9h7V60qff3SVobHr996CTwgxubgyQYEpg290h9J0buyECNNJexkFm5sOajh5G116RYA1c8ZMSw==}
     dev: true
 
+  /neo-async@2.6.2:
+    resolution: {integrity: sha512-Yd3UES5mWCSqR+qNT93S3UoYUkqAZ9lLg8a7g9rimsWmYGK8cVToA4/sF3RrshdyV3sAGMXVUmpMYOw+dLpOuw==}
+    dev: false
+
   /node-fetch@2.7.0:
     resolution: {integrity: sha512-c4FRfUm/dbcWZ7U+1Wq0AwCyFL+3nt2bEw05wfxSz+DWpWsitgmSgYmy2dQdWyKC1694ELPqMs/YzUSNozLt8A==}
     engines: {node: 4.x || >=6.0.0}
@@ -3802,6 +3821,11 @@ packages:
     engines: {node: '>=0.10.0'}
     dev: true
 
+  /source-map@0.6.1:
+    resolution: {integrity: sha512-UjgapumWlbMhkBgzT7Ykc5YXUT46F0iKu8SGXq0bcwP5dz/h0Plj6enJqjz1Zbq2l5WaqYnrVbwWOWMyF3F47g==}
+    engines: {node: '>=0.10.0'}
+    dev: false
+
   /source-map@0.8.0-beta.0:
     resolution: {integrity: sha512-2ymg6oRBpebeZi9UUNsgQ89bhx01TcTkmNTGnNO88imTmbSgy4nfujrgVEFKWpMTEGA11EDkTt7mqObTPdigIA==}
     engines: {node: '>= 8'}
@@ -4154,6 +4178,14 @@ packages:
     resolution: {integrity: sha512-Y7HYmWaFwPUmkoQCUIAYpKqkOf+SbVj/2fJJZ4RJMCfZp0rTGwRbzQD+HghfnhKOjL9E01okqz+ncJskGYfBNw==}
     dev: true
 
+  /uglify-js@3.17.4:
+    resolution: {integrity: sha512-T9q82TJI9e/C1TAxYvfb16xO120tMVFZrGA3f9/P4424DNu6ypK103y0GPFVa17yotwSyZW5iYXgjYHkGrJW/g==}
+    engines: {node: '>=0.8.0'}
+    hasBin: true
+    requiresBuild: true
+    dev: false
+    optional: true
+
   /unbox-primitive@1.0.2:
     resolution: {integrity: sha512-61pPlCD9h51VoreyJ0BReideM3MDKMKnh6+V9L08331ipq6Q8OFXZYiqP6n/tbHx4s5I9uRhcye6BrbkizkBDw==}
     dependencies:
@@ -4407,6 +4439,10 @@ packages:
     engines: {node: '>=0.10.0'}
     dev: true
 
+  /wordwrap@1.0.0:
+    resolution: {integrity: sha512-gvVzJFlPycKc5dZN4yPkP8w7Dc37BtP1yczEneOb4uq34pXZcvrtRTmWV8W+Ume+XCxKgbjM+nevkyFPMybd4Q==}
+    dev: false
+
   /wrap-ansi@7.0.0:
     resolution: {integrity: sha512-YVGIj2kamLSTxw6NsZjoBxfSwsn0ycdesmc4p+Q21c5zPuZ1pl+NfxVdxPtdHvmNVOQ6XSYG4AUtyt/Fi7D16Q==}
     engines: {node: '>=10'}

src/index.ts

@@ -1,4 +1,5 @@
 import { makeNixCommandArgs } from "./nix.js";
+import { renderCommitMessage } from "./template.js";
 import * as actionsCore from "@actions/core";
 import * as actionsExec from "@actions/exec";
 import { DetSysAction, inputs } from "detsys-ts";
@@ -12,6 +13,7 @@ const EVENT_EXECUTION_FAILURE = "execution_failure";
 
 class UpdateFlakeLockAction extends DetSysAction {
   private commitMessage: string;
+  private commitMessageTemplate: string;
   private nixOptions: string[];
   private flakeInputs: string[];
   private pathToFlakeDir: string | null;
@@ -26,6 +28,7 @@ class UpdateFlakeLockAction extends DetSysAction {
     });
 
     this.commitMessage = inputs.getString("commit-msg");
+    this.commitMessageTemplate = inputs.getString("commit-msg-template");
     this.flakeInputs = inputs.getArrayOfStrings("inputs", "space");
     this.nixOptions = inputs.getArrayOfStrings("nix-options", "space");
     this.pathToFlakeDir = inputs.getStringOrNull("path-to-flake-dir");
@@ -57,6 +60,12 @@ class UpdateFlakeLockAction extends DetSysAction {
 
     actionsCore.debug(`Running flake lock update in directory \`${flakeDir}\``);
 
+    const flakeDotLock = `${flakeDir}/flake.lock`;
+    const commitMessage =
+      this.commitMessage !== ""
+        ? this.commitMessage
+        : renderCommitMessage(this.commitMessageTemplate, flakeDotLock);
+
     // Nix command of this form:
     // nix ${maybe nix options} flake ${"update" or "lock"} ${maybe --update-input flags} --commit-lock-file --commit-lockfile-summary ${commit message}
     // Example commands:
@@ -65,7 +74,7 @@ class UpdateFlakeLockAction extends DetSysAction {
     const nixCommandArgs: string[] = makeNixCommandArgs(
       this.nixOptions,
       this.flakeInputs,
-      this.commitMessage,
+      commitMessage,
     );
 
     actionsCore.debug(

src/template.test.ts

@@ -0,0 +1,31 @@
+import { renderCommitMessage } from "./template.js";
+import { describe, expect, test } from "vitest";
+
+describe("templating", () => {
+  test("commit message", () => {
+    type TestCase = {
+      template: string;
+      flakeDotLock: string;
+      expected: string;
+    };
+
+    const testCases: TestCase[] = [
+      {
+        template: "Updating lockfile at {{ flake_dot_lock }}",
+        flakeDotLock: "./flake.lock",
+        expected: "Updating lockfile at ./flake.lock",
+      },
+      {
+        template:
+          "Here I go doing some updating of my pristine flake.lock at {{ flake_dot_lock }}",
+        flakeDotLock: "subflake/flake.lock",
+        expected:
+          "Here I go doing some updating of my pristine flake.lock at subflake/flake.lock",
+      },
+    ];
+
+    testCases.forEach(({ template, flakeDotLock, expected }) => {
+      expect(renderCommitMessage(template, flakeDotLock)).toEqual(expected);
+    });
+  });
+});

src/template.ts

@@ -0,0 +1,13 @@
+import Handlebars from "handlebars";
+
+export function renderCommitMessage(
+  template: string,
+  flakeDotLock: string,
+): string {
+  return render(template, { flake_dot_lock: flakeDotLock });
+}
+
+function render(template: string, inputs: Record<string, string>): string {
+  const tpl = Handlebars.compile(template);
+  return tpl(inputs);
+}