Add renderTemplateFromFile helper to consolidate file-based template rendering

actions/setup/js/checkout_pr_branch.cjs

@@ -26,9 +26,8 @@
  */
 
 const { getErrorMessage } = require("./error_helpers.cjs");
-const { renderTemplate } = require("./messages_core.cjs");
+const { renderTemplateFromFile } = require("./messages_core.cjs");
 const { detectForkPR } = require("./pr_helpers.cjs");
-const fs = require("fs");
 const { ERR_API } = require("./error_codes.cjs");
 
 /**
@@ -277,8 +276,7 @@ Pull request #${pullRequest.number} is closed. The checkout failed because the b
 
     // Load and render step summary template
     const templatePath = `${process.env.RUNNER_TEMP}/gh-aw/prompts/pr_checkout_failure.md`;
-    const template = fs.readFileSync(templatePath, "utf8");
-    const summaryContent = renderTemplate(template, {
+    const summaryContent = renderTemplateFromFile(templatePath, {
       error_message: errorMsg,
     });
 

actions/setup/js/checkout_pr_branch.test.cjs

@@ -93,7 +93,8 @@ describe("checkout_pr_branch.cjs", () => {
       }
       if (module === "./messages_core.cjs") {
         return {
-          renderTemplate: (template, context) => {
+          renderTemplateFromFile: (templatePath, context) => {
+            const template = mockRequire("fs").readFileSync(templatePath, "utf8");
             return template.replace(/\{(\w+)\}/g, (match, key) => {
               const value = context[key];
               return value !== undefined && value !== null ? String(value) : match;

actions/setup/js/create_issue.cjs

@@ -36,13 +36,12 @@ const { resolveTargetRepoConfig, resolveAndValidateRepo } = require("./repo_help
 const { createAuthenticatedGitHubClient } = require("./handler_auth.cjs");
 const { removeDuplicateTitleFromDescription } = require("./remove_duplicate_title.cjs");
 const { getErrorMessage } = require("./error_helpers.cjs");
-const { renderTemplate } = require("./messages_core.cjs");
+const { renderTemplateFromFile } = require("./messages_core.cjs");
 const { createExpirationLine, addExpirationToFooter } = require("./ephemerals.cjs");
 const { MAX_SUB_ISSUES, getSubIssueCount } = require("./sub_issue_helpers.cjs");
 const { closeOlderIssues } = require("./close_older_issues.cjs");
 const { parseBoolTemplatable } = require("./templatable.cjs");
 const { tryEnforceArrayLimit } = require("./limit_enforcement_helpers.cjs");
-const fs = require("fs");
 const { logStagedPreviewInfo } = require("./staged_preview.cjs");
 const { buildWorkflowRunUrl } = require("./workflow_metadata_helpers.cjs");
 const { MAX_LABELS, MAX_ASSIGNEES } = require("./constants.cjs");
@@ -167,19 +166,16 @@ function createParentIssueTemplate(groupId, titlePrefix, workflowName, workflowS
   // Use applyTitlePrefix to ensure proper spacing after prefix
   const title = applyTitlePrefix(`${groupId} - Issue Group`, titlePrefix);
 
-  // Load issue template
-  const issueTemplatePath = `${process.env.RUNNER_TEMP}/gh-aw/prompts/issue_group_parent.md`;
-  const issueTemplate = fs.readFileSync(issueTemplatePath, "utf8");
-
   // Create template context
   const templateContext = {
     group_id: groupId,
     workflow_name: workflowName,
     workflow_source_url: workflowSourceURL || "#",
   };
 
-  // Render the issue template
-  let body = renderTemplate(issueTemplate, templateContext);
+  // Load and render the issue template
+  const issueTemplatePath = `${process.env.RUNNER_TEMP}/gh-aw/prompts/issue_group_parent.md`;
+  let body = renderTemplateFromFile(issueTemplatePath, templateContext);
 
   // Add footer with workflow information
   const footer = `\n\n> Workflow: [${workflowName}](${workflowSourceURL})`;

actions/setup/js/create_pull_request.cjs

@@ -25,7 +25,7 @@ const { getBaseBranch } = require("./get_base_branch.cjs");
 const { createAuthenticatedGitHubClient } = require("./handler_auth.cjs");
 const { buildWorkflowRunUrl } = require("./workflow_metadata_helpers.cjs");
 const { checkFileProtection } = require("./manifest_file_helpers.cjs");
-const { renderTemplate } = require("./messages_core.cjs");
+const { renderTemplateFromFile } = require("./messages_core.cjs");
 const { COPILOT_REVIEWER_BOT, FAQ_CREATE_PR_PERMISSIONS_URL } = require("./constants.cjs");
 
 /**
@@ -985,8 +985,7 @@ ${patchPreview}`;
         const runId = context.runId;
         const patchFileName = patchFilePath ? patchFilePath.replace("/tmp/gh-aw/", "") : "aw-unknown.patch";
         const pushFailedTemplatePath = `${process.env.RUNNER_TEMP}/gh-aw/prompts/manifest_protection_push_failed_fallback.md`;
-        const pushFailedTemplate = fs.readFileSync(pushFailedTemplatePath, "utf8");
-        fallbackBody = renderTemplate(pushFailedTemplate, {
+        fallbackBody = renderTemplateFromFile(pushFailedTemplatePath, {
           main_body: mainBodyContent,
           footer: footerContent,
           files: filesFormatted,
@@ -1004,8 +1003,7 @@ ${patchPreview}`;
         const encodedHead = branchName.split("/").map(encodeURIComponent).join("/");
         const createPrUrl = `${githubServer}/${repoParts.owner}/${repoParts.repo}/compare/${encodedBase}...${encodedHead}?expand=1&title=${encodeURIComponent(title)}`;
         const templatePath = `${process.env.RUNNER_TEMP}/gh-aw/prompts/manifest_protection_create_pr_fallback.md`;
-        const template = fs.readFileSync(templatePath, "utf8");
-        fallbackBody = renderTemplate(template, {
+        fallbackBody = renderTemplateFromFile(templatePath, {
           main_body: mainBodyContent,
           footer: footerContent,
           files: filesFormatted,
@@ -1188,8 +1186,7 @@ ${patchPreview}`;
         }
 
         const fallbackTemplatePath = `${process.env.RUNNER_TEMP}/gh-aw/prompts/pr_permission_denied_fallback.md`;
-        const fallbackTemplate = fs.readFileSync(fallbackTemplatePath, "utf8");
-        const fallbackBody = renderTemplate(fallbackTemplate, {
+        const fallbackBody = renderTemplateFromFile(fallbackTemplatePath, {
           body,
           branch_name: branchName,
           create_pr_url: createPrUrl,

actions/setup/js/handle_agent_failure.cjs

@@ -4,7 +4,7 @@
 const { getErrorMessage } = require("./error_helpers.cjs");
 const { sanitizeContent } = require("./sanitize_content.cjs");
 const { getFooterAgentFailureIssueMessage, getFooterAgentFailureCommentMessage, generateXMLMarker } = require("./messages.cjs");
-const { renderTemplate } = require("./messages_core.cjs");
+const { renderTemplate, renderTemplateFromFile } = require("./messages_core.cjs");
 const { getCurrentBranch } = require("./get_current_branch.cjs");
 const { createExpirationLine, generateFooterWithExpiration } = require("./ephemerals.cjs");
 const { MAX_SUB_ISSUES, getSubIssueCount } = require("./sub_issue_helpers.cjs");
@@ -609,8 +609,7 @@ function buildTimeoutContext(isTimedOut, timeoutMinutes) {
   const suggestedMinutes = currentMinutes + 10;
 
   const templatePath = `${process.env.RUNNER_TEMP}/gh-aw/prompts/agent_timeout.md`;
-  const template = fs.readFileSync(templatePath, "utf8");
-  return "\n" + renderTemplate(template, { current_minutes: currentMinutes, suggested_minutes: suggestedMinutes });
+  return "\n" + renderTemplateFromFile(templatePath, { current_minutes: currentMinutes, suggested_minutes: suggestedMinutes });
 }
 
 /**
@@ -639,8 +638,7 @@ function buildAppTokenMintingFailedContext(hasAppTokenMintingFailed) {
   }
 
   const templatePath = "/opt/gh-aw/prompts/app_token_minting_failed.md";
-  const template = fs.readFileSync(templatePath, "utf8");
-  return "\n" + renderTemplate(template, {});
+  return "\n" + renderTemplateFromFile(templatePath, {});
 }
 
 /**

actions/setup/js/handle_noop_message.cjs

@@ -6,7 +6,7 @@ const { getErrorMessage } = require("./error_helpers.cjs");
 const { ERR_API } = require("./error_codes.cjs");
 const { sanitizeContent } = require("./sanitize_content.cjs");
 const { generateFooterWithExpiration } = require("./ephemerals.cjs");
-const { renderTemplate } = require("./messages_core.cjs");
+const { renderTemplateFromFile } = require("./messages_core.cjs");
 
 /**
  * Search for or create the parent issue for all agentic workflow no-op runs
@@ -139,12 +139,9 @@ async function main() {
       return;
     }
 
-    // Load comment template from file
+    // Load and render comment template from file
     const commentTemplatePath = `${process.env.RUNNER_TEMP}/gh-aw/prompts/noop_comment.md`;
-    const commentTemplate = fs.readFileSync(commentTemplatePath, "utf8");
-
-    // Build the comment body by replacing template variables
-    const commentBody = renderTemplate(commentTemplate, {
+    const commentBody = renderTemplateFromFile(commentTemplatePath, {
       workflow_name: workflowName,
       message: noopMessage,
       run_url: runUrl,

actions/setup/js/messages.cjs

@@ -28,7 +28,7 @@
  */
 
 // Re-export core utilities
-const { getMessages, renderTemplate } = require("./messages_core.cjs");
+const { getMessages, renderTemplate, renderTemplateFromFile } = require("./messages_core.cjs");
 
 // Re-export footer messages
 const { getFooterMessage, getFooterInstallMessage, getFooterAgentFailureIssueMessage, getFooterAgentFailureCommentMessage, generateFooterWithMessages, generateXMLMarker } = require("./messages_footer.cjs");
@@ -45,6 +45,7 @@ const { getCloseOlderDiscussionMessage } = require("./messages_close_discussion.
 module.exports = {
   getMessages,
   renderTemplate,
+  renderTemplateFromFile,
   getFooterMessage,
   getFooterInstallMessage,
   getFooterAgentFailureIssueMessage,

actions/setup/js/messages_core.cjs

@@ -22,6 +22,7 @@
  */
 
 const { getErrorMessage } = require("./error_helpers.cjs");
+const fs = require("fs");
 
 /**
  * @typedef {Object} SafeOutputMessages
@@ -78,6 +79,18 @@ function renderTemplate(template, context) {
   });
 }
 
+/**
+ * Read a template file and render it with the given context.
+ * Combines file loading and template rendering into a single helper.
+ * @param {string} templatePath - Absolute path to the template file
+ * @param {Record<string, string|number|boolean|undefined>} context - Key-value pairs for replacement
+ * @returns {string} Rendered template with placeholders replaced
+ */
+function renderTemplateFromFile(templatePath, context) {
+  const template = fs.readFileSync(templatePath, "utf8");
+  return renderTemplate(template, context);
+}
+
 /**
  * Convert context object keys to snake_case for template rendering.
  * Also keeps original camelCase keys for backwards compatibility.
@@ -101,5 +114,6 @@ function toSnakeCase(obj) {
 module.exports = {
   getMessages,
   renderTemplate,
+  renderTemplateFromFile,
   toSnakeCase,
 };

actions/setup/js/messages_core.test.cjs

@@ -3,10 +3,14 @@
  *
  * Tests for the core message utilities module including:
  * - Template rendering with placeholder replacement
+ * - Template rendering from file
  * - Snake_case conversion with camelCase compatibility
  * - Messages config parsing from environment variable
  */
 import { describe, it, expect, beforeEach, vi } from "vitest";
+import fs from "fs";
+import os from "os";
+import path from "path";
 
 const mockCore = {
   debug: vi.fn(),
@@ -78,6 +82,60 @@ describe("messages_core.cjs", () => {
     });
   });
 
+  describe("renderTemplateFromFile", () => {
+    it("should read a file and render its contents as a template", async () => {
+      const { renderTemplateFromFile } = await import("./messages_core.cjs?" + Date.now());
+      const tmpFile = path.join(os.tmpdir(), `msg-core-test-${Date.now()}.md`);
+      fs.writeFileSync(tmpFile, "Hello, {name}!", "utf8");
+      try {
+        const result = renderTemplateFromFile(tmpFile, { name: "World" });
+        expect(result).toBe("Hello, World!");
+      } finally {
+        fs.unlinkSync(tmpFile);
+      }
+    });
+
+    it("should replace multiple placeholders from a file", async () => {
+      const { renderTemplateFromFile } = await import("./messages_core.cjs?" + Date.now());
+      const tmpFile = path.join(os.tmpdir(), `msg-core-test-${Date.now()}.md`);
+      fs.writeFileSync(tmpFile, "{greeting}, {name}! Run: {run_url}", "utf8");
+      try {
+        const result = renderTemplateFromFile(tmpFile, {
+          greeting: "Hello",
+          name: "Alice",
+          run_url: "https://github.com/actions/runs/123",
+        });
+        expect(result).toBe("Hello, Alice! Run: https://github.com/actions/runs/123");
+      } finally {
+        fs.unlinkSync(tmpFile);
+      }
+    });
+
+    it("should leave unknown placeholders unchanged", async () => {
+      const { renderTemplateFromFile } = await import("./messages_core.cjs?" + Date.now());
+      const tmpFile = path.join(os.tmpdir(), `msg-core-test-${Date.now()}.md`);
+      fs.writeFileSync(tmpFile, "Hello, {name}! {unknown}", "utf8");
+      try {
+        const result = renderTemplateFromFile(tmpFile, { name: "World" });
+        expect(result).toBe("Hello, World! {unknown}");
+      } finally {
+        fs.unlinkSync(tmpFile);
+      }
+    });
+
+    it("should return file contents unchanged when context is empty", async () => {
+      const { renderTemplateFromFile } = await import("./messages_core.cjs?" + Date.now());
+      const tmpFile = path.join(os.tmpdir(), `msg-core-test-${Date.now()}.md`);
+      fs.writeFileSync(tmpFile, "No placeholders here.", "utf8");
+      try {
+        const result = renderTemplateFromFile(tmpFile, {});
+        expect(result).toBe("No placeholders here.");
+      } finally {
+        fs.unlinkSync(tmpFile);
+      }
+    });
+  });
+
   describe("toSnakeCase", () => {
     it("should convert camelCase keys to snake_case", async () => {
       const { toSnakeCase } = await import("./messages_core.cjs?" + Date.now());

actions/setup/js/missing_issue_helpers.cjs

@@ -2,9 +2,8 @@
 /// <reference types="@actions/github-script" />
 
 const { getErrorMessage } = require("./error_helpers.cjs");
-const { renderTemplate } = require("./messages_core.cjs");
+const { renderTemplateFromFile } = require("./messages_core.cjs");
 const { generateFooterWithExpiration } = require("./ephemerals.cjs");
-const fs = require("fs");
 const { sanitizeContent } = require("./sanitize_content.cjs");
 
 /**
@@ -111,9 +110,6 @@ function buildMissingIssueHandler(options) {
           // No existing issue, create a new one
           core.info("No existing issue found, creating a new one");
 
-          // Load issue template
-          const issueTemplate = fs.readFileSync(templatePath, "utf8");
-
           // Build items list for template
           const issueListLines = [];
           items.forEach((item, index) => {
@@ -129,8 +125,8 @@ function buildMissingIssueHandler(options) {
             [templateListKey]: issueListLines.join("\n"),
           };
 
-          // Render the issue template
-          const issueBodyContent = renderTemplate(issueTemplate, templateContext);
+          // Load and render the issue template
+          const issueBodyContent = renderTemplateFromFile(templatePath, templateContext);
 
           // Add expiration marker (1 week from now) in a quoted section using helper
           const footer = generateFooterWithExpiration({

actions/setup/js/push_to_pull_request_branch.cjs

@@ -14,7 +14,7 @@ const { resolveTargetRepoConfig, resolveAndValidateRepo } = require("./repo_help
 const { createAuthenticatedGitHubClient } = require("./handler_auth.cjs");
 const { checkFileProtection } = require("./manifest_file_helpers.cjs");
 const { buildWorkflowRunUrl } = require("./workflow_metadata_helpers.cjs");
-const { renderTemplate } = require("./messages_core.cjs");
+const { renderTemplateFromFile } = require("./messages_core.cjs");
 const { getGitAuthEnv } = require("./git_helpers.cjs");
 
 /**
@@ -338,8 +338,7 @@ async function main(config = {}) {
       const prUrl = `${githubServer}/${repoParts.owner}/${repoParts.repo}/pull/${pullNumber}`;
       const issueTitle = `[gh-aw] Protected Files: ${prTitle || `PR #${pullNumber}`}`;
       const templatePath = `${process.env.RUNNER_TEMP}/gh-aw/prompts/manifest_protection_push_to_pr_fallback.md`;
-      const template = fs.readFileSync(templatePath, "utf8");
-      const issueBody = renderTemplate(template, {
+      const issueBody = renderTemplateFromFile(templatePath, {
         files: protectedFilesForFallback.map(f => `\`${f}\``).join(", "),
         pull_number: pullNumber,
         pr_url: prUrl,