From ca574601d1eb2ffa5445a4ceb8024a38ac580c5d Mon Sep 17 00:00:00 2001
From: Heidi <clippii@protonmail.com>
Date: Fri, 15 May 2026 00:27:08 +0100
Subject: [PATCH] meow

---
 .env.example |  6 +++++
 README.md    | 11 ++++++++
 server.js    | 74 +++++++++++++++++++++++++++++++++++++++++-----------
 3 files changed, 76 insertions(+), 15 deletions(-)

diff --git a/.env.example b/.env.example
index fb886be..af18faa 100644
--- a/.env.example
+++ b/.env.example
@@ -8,3 +8,9 @@ WEBHOOK_SECRET=
 
 # Optional. Override if pm2 is not available as "pm2" on PATH.
 PM2_BIN=
+
+# Optional. Override if npm is not available as "npm" on PATH.
+NPM_BIN=
+
+# Optional. Override if git is not available as "git" on PATH.
+GIT_BIN=
diff --git a/README.md b/README.md
index 68e7cfc..eccee3b 100644
--- a/README.md
+++ b/README.md
@@ -25,6 +25,15 @@ The app name is `linkweb`. The GitHub webhook receiver is:
 POST /webhook/github
 ```
 
+On a valid webhook request, the server runs:
+
+```sh
+git pull --ff-only
+npm install
+npm run build
+pm2 restart linkweb
+```
+
 Set `WEBHOOK_SECRET` in `ecosystem.config.cjs` if you want GitHub `x-hub-signature-256` verification:
 
 ```js
@@ -36,3 +45,5 @@ env: {
   WEBHOOK_SECRET: 'your-secret',
 }
 ```
+
+You can also set `PM2_BIN`, `NPM_BIN`, or `GIT_BIN` if a command is not available on the production `PATH`.
diff --git a/server.js b/server.js
index fed2489..72671ba 100644
--- a/server.js
+++ b/server.js
@@ -11,6 +11,10 @@ const webhookPath = process.env.WEBHOOK_PATH || '/webhook/github';
 const webhookSecret = process.env.WEBHOOK_SECRET || '';
 const pm2AppName = process.env.PM2_APP_NAME || 'linkweb';
 const pm2Command = process.env.PM2_BIN || (process.platform === 'win32' ? 'pm2.cmd' : 'pm2');
+const npmCommand = process.env.NPM_BIN || (process.platform === 'win32' ? 'npm.cmd' : 'npm');
+const gitCommand = process.env.GIT_BIN || 'git';
+
+let deployInProgress = false;
 
 function verifyGitHubSignature(req) {
   if (!webhookSecret) {
@@ -33,27 +37,67 @@ function verifyGitHubSignature(req) {
   return received.length === expected.length && crypto.timingSafeEqual(received, expected);
 }
 
+function runStep(label, command, args) {
+  console.log(`[deploy] ${label}`);
+
+  return new Promise((resolve, reject) => {
+    execFile(
+      command,
+      args,
+      {
+        cwd: __dirname,
+        maxBuffer: 1024 * 1024 * 10,
+        windowsHide: true,
+      },
+      (error, stdout, stderr) => {
+        if (stdout) {
+          console.log(stdout);
+        }
+
+        if (stderr) {
+          console.error(stderr);
+        }
+
+        if (error) {
+          reject(error);
+          return;
+        }
+
+        resolve();
+      },
+    );
+  });
+}
+
+async function runDeploy() {
+  if (deployInProgress) {
+    console.log('[deploy] Webhook ignored because a deploy is already running.');
+    return;
+  }
+
+  deployInProgress = true;
+
+  try {
+    await runStep('Pulling latest changes', gitCommand, ['pull', '--ff-only']);
+    await runStep('Installing dependencies', npmCommand, ['install']);
+    await runStep('Building site', npmCommand, ['run', 'build']);
+    await runStep(`Restarting PM2 app "${pm2AppName}"`, pm2Command, ['restart', pm2AppName]);
+    console.log('[deploy] Complete.');
+  } catch (error) {
+    console.error('[deploy] Failed:', error.message);
+  } finally {
+    deployInProgress = false;
+  }
+}
+
 app.post(webhookPath, express.raw({ type: '*/*' }), (req, res) => {
   if (!verifyGitHubSignature(req)) {
     res.status(401).json({ ok: false, error: 'Invalid webhook signature' });
     return;
   }
 
-  res.status(202).json({ ok: true, restarting: pm2AppName });
-
-  execFile(pm2Command, ['restart', pm2AppName], (error, stdout, stderr) => {
-    if (error) {
-      console.error('PM2 restart failed:', error.message);
-      if (stderr) {
-        console.error(stderr);
-      }
-      return;
-    }
-
-    if (stdout) {
-      console.log(stdout);
-    }
-  });
+  res.status(202).json({ ok: true, deploying: pm2AppName });
+  runDeploy();
 });
 
 app.get('/healthz', (_req, res) => {