Automate issue-to-draft-PR creation for new issues

.github/workflows/issue-to-draft-pr.yml

@@ -0,0 +1,123 @@
+name: Issue to draft PR
+
+on:
+  issues:
+    types: [opened]
+  workflow_dispatch:
+
+permissions: {}
+
+jobs:
+  create-draft-pr:
+    permissions:
+      contents: write
+      issues: write
+      pull-requests: write
+    runs-on: blacksmith-16vcpu-ubuntu-2404
+    steps:
+      - uses: actions/create-github-app-token@d72941d797fd3113feb6b93fd0dec494b13a2547 # v1
+        id: app-token
+        continue-on-error: true
+        with:
+          app-id: "2729701"
+          private-key: ${{ secrets.GH_APP_PRIVATE_KEY }}
+
+      - uses: actions/create-github-app-token@d72941d797fd3113feb6b93fd0dec494b13a2547 # v1
+        id: app-token-fallback
+        if: steps.app-token.outcome == 'failure'
+        with:
+          app-id: "2971289"
+          private-key: ${{ secrets.GH_APP_PRIVATE_KEY_FALLBACK }}
+
+      - name: Create issue branch and draft PR
+        uses: actions/github-script@f28e40c7f34bde8b3046d885e986cb6290c5673b # v7
+        with:
+          github-token: ${{ steps.app-token.outputs.token || steps.app-token-fallback.outputs.token }}
+          script: |
+            const issue = context.payload.issue;
+            if (!issue) {
+              core.info("No issue payload found, skipping.");
+              return;
+            }
+
+            const owner = context.repo.owner;
+            const repo = context.repo.repo;
+            const issueNumber = issue.number;
+            const issueTitle = (issue.title ?? `Issue ${issueNumber}`).trim();
+            const issueBody = (issue.body ?? "").trim() || "_No description provided._";
+            const issueUrl = issue.html_url;
+            const branchName = `issue-${issueNumber}`;
+            const prTitle = `[Issue #${issueNumber}] ${issueTitle}`;
+
+            const existingPrs = await github.rest.pulls.list({
+              owner,
+              repo,
+              head: `${owner}:${branchName}`,
+              state: "all",
+              per_page: 1,
+            });
+
+            if (existingPrs.data.length > 0) {
+              core.info(`PR already exists for ${branchName}, skipping creation.`);
+              return;
+            }
+
+            let branchExists = true;
+            try {
+              await github.rest.repos.getBranch({
+                owner,
+                repo,
+                branch: branchName,
+              });
+            } catch (error) {
+              if (error.status === 404) {
+                branchExists = false;
+              } else {
+                throw error;
+              }
+            }
+
+            if (!branchExists) {
+              const mainBranch = await github.rest.repos.getBranch({
+                owner,
+                repo,
+                branch: "main",
+              });
+
+              await github.rest.git.createRef({
+                owner,
+                repo,
+                ref: `refs/heads/${branchName}`,
+                sha: mainBranch.data.commit.sha,
+              });
+            }
+
+            const prBody = [
+              "## Source issue",
+              `- #${issueNumber}`,
+              `- ${issueUrl}`,
+              "",
+              "## Original issue description",
+              issueBody,
+              "",
+              `Related to #${issueNumber}`,
+            ].join("\n");
+
+            const createdPr = await github.rest.pulls.create({
+              owner,
+              repo,
+              title: prTitle,
+              head: branchName,
+              base: "main",
+              body: prBody,
+              draft: true,
+            });
+
+            await github.rest.issues.createComment({
+              owner,
+              repo,
+              issue_number: issueNumber,
+              body: `Opened draft PR #${createdPr.data.number}: ${createdPr.data.html_url}`,
+            });
+
+            core.info(`Created draft PR #${createdPr.data.number} for issue #${issueNumber}.`);