Fix webhook pull

bin/pull.sh

+#!/usr/bin/env bash
+
+git fetch &&
+git reset --hard origin/master &&
+npm install &&
+npm run build

src/backend/common/util.js

@@ -12,12 +12,21 @@ const execute = (command, cwd, { stdout = process.stdout, stderr = process.stder
   if (stderr) child.stderr.pipe(stderr);
 });
 
+const spawn = (command, args, cwd, { stdout = process.stdout, stderr = process.stderr } = {}) => new Promise((resolve, reject) => {
+  if (!cwd) return reject(new Error('CWD Not Specified'));
+  const child = child_process.spawn(command, args, { cwd });
+  child.on('close', code => code ? reject(new Error(`Process exited with code: ${code}`)) : resolve());
+  if (stdout) child.stdout.pipe(stdout);
+  if (stderr) child.stderr.pipe(stderr);
+});
+
 const createKey = name => name.toLowerCase().replace(/ /g, '-');
 
 const listFiles = dirPath => fs.readdirSync(dirPath).filter(fileName => !fileName.startsWith('.'));
 
 export {
   execute,
+  spawn,
   createKey,
   listFiles,
 };

src/backend/index.js

@@ -6,7 +6,7 @@ import bodyParser from 'body-parser';
 import * as controllers from '/controllers';
 import { ClientError, ForbiddenError, NotFoundError, UnauthorizedError } from '/common/error';
 import webhook from '/common/webhook';
-import { execute } from '/common/util';
+import { spawn } from '/common/util';
 
 const app = express();
 app.use(morgan('tiny'));
@@ -34,13 +34,7 @@ const rootPath = path.resolve(__dirname, '..', '..');
 webhook.on('algorithm-visualizer', event => {
   switch (event) {
     case 'push':
-      execute([
-        'git fetch',
-        'git reset --hard origin/master',
-        'npm install',
-        'npm run build',
-        'pm2 startOrRestart ./pm2.config.js',
-      ].join(' && '), rootPath);
+      spawn('sh', ['./bin/pull.sh'], rootPath).then(() => process.exit(0));
       break;
   }
 });