Follow the steps to automatically pull update when the project is pushed to master branch
根据以下步骤操作，当项目的 master 分支被推时，将自动拉取更新

Config in the Github webside
在 GitHub 网站中设置

Project - Setting -- Webhooks -- Add webhook
项目 -- 设置 -- 网络钩子 -- 增加网络钩子

nono /etc/profile.d/github-webhook.sh

export GITHUB_WEBHOOK_PORT=NUMBER
export GITHUB_WEBHOOK_SECRET=STRING

source /etc/profile

Change NUMBER and STRING to what you like, and if not variable is added, the app will use 3000 as default port, without secret
跟据喜好更改 NUMBER 和 STRING，如果没有添加任何变量，应用将使用 3000 作为默认端口，并不使用密钥

cd PROJECT_PARENT
git clone git@github.com:vinzid/github-webhook.git
cd github-webhook
pm2 start app.js --name github-webhook

PROJECT_PARENT is the directroy where project's directory is located; you can directly use ndoe app to substitue pm2 for testing
PROJECT_PARENT 为项目目录所在的目录；可以直接 ndoe app 替代 pm2 进行测试

pm2 startup
pm2 save

pm2 startup will create service which will run on startup, pm2 save will save the current running pm2 apps, as content to restore when reboot
pm2 startup 会创建并开启开机自动运行的服务， pm2 save 会保存当前的 pm2 运行应用，作为重启后的恢复内容

If the project need to be built after pull update, the local hook can be set, following is hexo blog as example
如果项目在拉取更新后需要构建，那么可以设置本地钩子，以下以 hexo 博客为例

cd blog/.git/hooks
nano post-merge

#!/bin/sh
yarn clean
yarn build

chmod +x post-merge