nocobase/docs/en-US/api/server/application.md

Application

Overview

Web Service

NocoBase Application is a web framework implemented based on Koa, compatible with Koa API.

// index.js
const { Application } = require('@nocobase/server');

// Create App instance and configure the database
const app = new Application({
    database: {
        dialect: 'sqlite',
        storage: ':memory:',
    }
});

// Register middleware, response to requests
app.use(async ctx => {
  ctx.body = 'Hello World';
});

// Run in the CLI mode
app.runAsCLI();

After running node index.js start in CLI to start service, use curl to request service.

$> curl localhost:3000
Hello World

CLI Tool

NocoBase Application has a built-in cli commander, which can be run as CLI tool.

// cmd.js
const {Application} = require('@nocobase/server');
const app = new Application({
  database: {
    dialect: 'sqlite',
    storage: ':memory:',
  }
});

app.cli.command('hello').action(async () => {
  console.log("hello world")
});

app.runAsCLI()

Run in CLI:

$> node cmd.js hello
hello world

Inject Plugin

NocoBase Application is designed as a highly extensible framework, plugins can be written and injected to extend the functionality of the application. For example, the above-mentioned Web service can be replaced with a plugin.

const { Application, Plugin } = require('@nocobase/server');

// Write plugin by inheriting the Plugin class
class HelloWordPlugin extends Plugin {
  load() {
    this.app.use(async (ctx, next) => {
      ctx.body = "Hello World";
    })
  }
}

const app = new Application({
  database: {
    dialect: 'sqlite',
    storage: ':memory:',
  }
});

// Inject plugin
app.plugin(HelloWordPlugin, { name: 'hello-world-plugin'} );

app.runAsCLI()

More Examples

Please refer to the detailed guides of plugin development. Read more examples of the Application class.

Life Cycle

Depending on the running mode, the Application has three life cycle stages.

Install

Use the install command in cli to invoke the installation. Generally, if needs to write new tables or data to the database before using the plugin, you need to do it during installation. Installation is also required when using NocoBase for the first time.

• Call the load method to load registered plugins.
• Trigger the beforeInstall event.
• Call the db.sync method to synchronize database.
• Call the pm.install method to execute the install methods of registered plugins.
• Write the version of nocobase.
• Trigger the afterInstall event.
• Call the stop method to end installation.

Start

Use the start command in cli to start NocoBase Web service.

• Call the load method to load registered plugins.
• Call the start medthod:
  • Trigger the beforeStart event
  • Start port listening
  • Trigger the afterStart event

Upgrade

Use the upgrade command in cli to upgrade NocoBase Web service when needed.

• Call the load method to load registered plugins.
• Trigger the beforeUpgrade event.
• Call the db.migrator.up method to migrate database.
• Call the db.sync method to synchronize database.
• Call the version.update method to update the version of nocobase.
• Trigger the afterUpgrade event.
• Call the stop medthod to end upgrade.

Constructor

constructor()

Create an instance.

Signature

• constructor(options: ApplicationOptions)

Parameters

Name	Type	Default	Description
options.database	IDatabaseOptions or Database	{}	Database configuration
options.resourcer	ResourcerOptions	{}	Resource route configuration
options.logger	AppLoggerOptions	{}	Log
options.cors	CorsOptions	{}	Cross-domain configuration, refer to @koa/cors
options.dataWrapping	boolean	true	Whether or not to wrap the response data, true will wrap the usual ctx.body into a { data, meta } structure.
options.registerActions	boolean	true	Whether or not to register the default actions
options.i18n	I18nOptions	{}	Internationalization configuration, refer to i18next
options.plugins	PluginConfiguration[]	[]	Configuration of the plugins enabled by default

Type

interface ApplicationOptions {

}

Instance Members

cli

CLI tool instance, refer to the npm package Commander。

db

Database instance, refer to Database for the related API.

resourcer

Resource route management instance created automatically during app initialization, refer to Resourcer for the related API.

acl

ACL instance, refer to ACL for the related API.

logger

Winston instance, refer to Winston for the related API.

i18n

I18next instance, refer to I18next for the related API.

pm

Plugin manager instance, refer to PluginManager for the related API.

version

App version instance, refer to ApplicationVersion for the related API.

middleware

Built-in middleware includes:

• logger
• i18next
• bodyParser
• cors
• dataWrapping
• db2resource
• restApiMiddleware

context

Context inherited from koa, accessible via app.context, is used to inject context-accessible content to each request. Refer to Koa Context.

NocoBase injects the following members to context by default, which can be used directly in the request function:

变量名	类型	描述
ctx.app	Application	应用实例
ctx.db	Database	数据库实例
ctx.resourcer	Resourcer	资源路由管理器实例
ctx.action	Action	资源操作相关对象实例
ctx.logger	Winston	日志实例
ctx.i18n	I18n	国际化实例
ctx.t	i18n.t	国际化翻译函数快捷方式
ctx.getBearerToken()	Function	获取请求头中的 bearer token

实例方法

use()

注册中间件，兼容所有 Koa 插件

on()

订阅应用级事件，主要与生命周期相关，等同于 eventEmitter.on()。所有可订阅事件参考 事件。

command()

自定义 command

findCommand()

查找已定义 command

runAsCLI()

以 CLI 的方式运行。

load()

加载应用配置。

签名

• async load(): Promise<void>

reload()

重载应用配置。

install()

初始化安装应用，同步安装插件。

upgrade()

升级应用，同步升级插件。

start()

启动应用，如果配置了监听的端口，将启动监听，之后应用即可接受 HTTP 请求。

签名

• async start(options: StartOptions): Promise<void>

参数

参数名	类型	默认值	描述
options.listen?	ListenOptions	{}	HTTP 监听参数对象
options.listen.port?	number	13000	端口
options.listen.host?	string	'localhost'	域名

stop()

停止应用，此方法会关闭数据库连接，关闭 HTTP 端口，不会删除数据。

destroy()

删除应用，此方法会删除应用对应的数据库。

事件

'beforeLoad' / 'afterLoad'

'beforeInstall' / 'afterInstall'

'beforeUpgrade' / 'afterUpgrade'

'beforeStart' / 'afterStart'

'beforeStop' / 'afterStop'

'beforeDestroy' / 'afterDestroy'