Deployment

Launching application via egg-bin dev will bring something magical to help people to develop in high efficiency. However, actually, those features are not required in production or any other environment. Let's walk through and learn how to deploy your application in Egg's way.

There are two steps to achieve building once and deploying multiply from source code to runtime.

# Build

In the stage, you don't need to compile JavaScript files unless TypeScript or Babel(ES6 features) are involved in stack.

Generally, before deploying the application, dependencies will be installed with NODE_ENV=production or --production, which will exclude devDependencies because those used in development may increase the size of package released or even create pitfalls that you never expect.

$ cd baseDir
$ npm install --production
$ tar -zcvf ../release.tgz .

Both the application and dependencies will be packed into a tgz file, what you are going to do is unzipping and launching it.

Reusable package brings a few pros in:

  • Environments in building and runtime are different, try to keep the later environment pure and stable.
  • Abbreviating publish progress and making rollback without hassle.

# Deploy

Node.js(>= 8.0.0) is required so that you should make sure it is pre-installed in runtime environment.

Egg takes egg-cluster to create Master process, which you can rely on to secure the application instead of daemon manager like pm2. The API is also really convenient for developers to achieve that, just egg.startCluster.

And framework also provide egg-scripts for developers to start/stop application at prod mode.

Firstly, we need to import egg-scripts as dependencies:

$ npm i egg-scripts --save

Then add npm scripts to package.json:

{
"scripts": {
"start": "egg-scripts start --daemon",
"stop": "egg-scripts stop"
}
}

Then we are able to use npm start and npm stop to manage application.

Note: egg-scripts has limited support for Windows, see #22.

# Start

$ egg-scripts start --port=7001 --daemon --title=egg-server-showcase

Options:

  • --port=7001 http server port, will use process.env.PORT, default to 7001.
  • --daemon whether run at background, so you don't need nohup. Ignore this when the application run in docker instance.
  • --env=prod then framework env, will use process.env.EGG_SERVER_ENV, default to prod
  • --workers=2 worker count, default to cpu cores, which can leverage the capability of the cpu.
  • --title=egg-server-showcase convenient for ps + grep, default to egg-server-${appname}.
  • --framework=yadan config egg.framework at package.json or pass this args, when you are using Custom Framework.
  • --ignore-stderr ignore the std err at start up。
  • support all options from egg-cluster, such as --https.

More about egg-scripts and egg-cluster documents.

# Dispatch with arguments

Arguments of dispatch can be configured in config.{env}.js.

// config/config.default.js

exports.cluster = {
listen: {
port: 7001,
hostname: '127.0.0.1',
// path: '/var/run/egg.sock',
}
}

server.listen supports arguments including path, port and hostname to change dispatching behavior. One thing you should know is that the port in egg.startCluster will override the one in application config.

# Stop

$ egg-scripts stop

This command will kill master process which will handler and notice worker and agent to gracefull exit.

Also you can manually call ps -eo "pid,command" | grep -- "--title=egg-server" to find master process then kill without -9.