egg-eureka-plus
v1.0.8
Published
eureka plugin for egg.js
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egg-eureka-plus
一款优雅的egg eureka插件!
使用理念
agent进程启动时,会用单例模式初始eureka实例,并注册服务,状态为OUT_OF_SERVICE(不可用,因为这时app worker并未开始启动)。
这时我们可以给项目里agent.js中的didReady声明周期,加入远程获取配置文件的方法,并保存文件到run目录中。
等app worker启动时,可以在configWillLoad声明周期中读取临时生成的remote配置文件,然后根据情况依次修改app.config的配置项。
最后在agent进程中使用agent.messenger.once方法监听egg-ready事件,如果所有app worker启动成功,则把服务状态OUT_OF_SERVICE改为UP。
安装
$ npm i egg-eureka-plus --save
配置
示例:(具体参考eureka-js-client)
// 项目名/config/plugin.js
const plugin = {
eureka: {
enable: true,
package: 'egg-eureka-plus',
},
};
// 项目名/config/config.default.js
config.eureka = {
client: {
instance: {
instanceId: '127.0.0.1:9999',
app: 'node-service',
hostName: '127.0.0.1',
ipAddr: '127.0.0.1',
statusPageUrl: `http://127.0.0.1:9999/eureka/info`, // spring admin 注册心跳
healthCheckUrl: `http://127.0.0.1:9999/eureka/health`, // eureka 注册心跳
port: {
$: port,
'@enabled': 'true',
},
vipAddress: 'node-service',
dataCenterInfo: {
'@class': 'com.netflix.appinfo.InstanceInfo$DefaultDataCenterInfo',
name: 'MyOwn',
},
},
eureka: {
registryFetchInterval: 3000,
// 有多个 eureka 集群
serviceUrls: {
default: ['http://10.0.0.110:8899/eureka/apps/'],
},
},
},
};
使用方式
挂载的app.eureka实例,主要开放4个api,分别是:
getServiceByAppId(appId: string): Promise<string>;
getServiceByVipAddress(vipAddress: string): Promise<string>;
getInstancesByAppId(
appId: string,
cb: (error: Error | null, config: EurekaClient.EurekaInstanceConfig[]) => void,
): void;
getInstancesByVipAddress(
vidAddress: string,
cb: (error: Error | null, config: EurekaClient.EurekaInstanceConfig[]) => void,
): void;
这4个api都是代理到agent进程进行去执行的,用来获取eureka注册中心上指定的服务地址。
应用示例
// 项目名/app.ts
import { Application, IBoot } from 'egg';
import { initConfig } from './lib/config_handler';
const sequelize = require('egg-sequelize/app');
export default class FooBoot implements IBoot {
constructor(private readonly app: Application) {}
async configWillLoad() {
// 从临时文件中读取agentWorker保存的远程配置文件,并修改当前项目中的config文件。
initConfig(this.app);
}
// Config, plugin files have been loaded.
configDidLoad() {
}
// All files have loaded, start plugin here.
async didLoad() {
}
// All plugins have started, can do some thing before app ready.
async willReady() {
// sequelize配置依赖于eureka插件,但官方egg-sequelize在worker启动时会检查配置文件参数类型,由于定义的模板格式不符合类型,所以这里手动延后执行。
sequelize(this.app);
}
// Worker is ready, can do some things
async didReady() {
}
// Server is listening.
async serverDidReady() {
}
// Do some thing before app close.
async beforeClose() {
}
}
// 项目名/agent.ts
import { Agent } from 'egg';
import { saveRemoteConfig, initConfig } from './lib/config_handler';
export default class AgentBootHook {
constructor(private readonly agent: Agent) {}
async didReady() {
// 把springCloud远程配置保存到临时文件,供appWorker调用。
await saveRemoteConfig(this.agent);
// 从临时文件中读取agentWorker保存的远程配置文件,并修改当前项目中的config文件。
initConfig(this.agent);
}
}
// 项目名/lib/config_handler.ts
import { Agent, EggApplication } from 'egg';
import * as fs from 'fs';
import * as path from 'path';
import * as assert from 'assert';
import * as YAML from 'yamljs';
import * as is from 'is-type-of';
// 临时写入的远程配置文件
export const runtimeFile = './run/eureka-remote-config.json';
/**
* 使用字符串深度获取对象属性
* @param object
* @param path
* @param defaultValue
*/
export const deepGet = (object, path, defaultValue?) => {
return (
(!Array.isArray(path)
? path
.replace(/\[/g, '.')
.replace(/\]/g, '')
.split('.')
: path
).reduce((o, k) => (o || {})[k], object) || defaultValue
);
};
/**
* 深度遍历配置文件,检查模板字段,并替换。
* @param obj
* @param cb
*/
export const depthSearch = (obj, config) => {
const regular = /^\$\{(.*)+\}$/;
for (const index in obj) {
const item = obj[index];
if (is.object(item)) {
depthSearch(item, config);
} else if (is.string(item) && regular.test(item)) {
// console.log(item, deepGet(config, temp[1], ''));
const temp = item.match(regular);
obj[index] = deepGet(config, temp[1], '');
}
}
};
/**
* agentWorker获取springCloud配置数据,
* 写入到运行时文件中,供appWorker调用。
* @param agent
*/
export const saveRemoteConfig = async (agent: Agent) => {
const { eureka, config } = agent;
const { configServer: { name, basicAuth, configFile } } = config.eureka.apps;
const instances = eureka.getInstancesByAppId(name);
assert(instances.length > 0, `springCloud配置中心${name}实例获取失败!`);
try {
const resp = await agent.curl(`${instances[0].homePageUrl}/${configFile}`, {
auth: `${basicAuth.username}:${basicAuth.password}`,
});
const configData = YAML.parse(resp.data.toString());
const tempConfigFile = path.join(agent.baseDir, runtimeFile);
fs.writeFileSync(tempConfigFile, JSON.stringify(configData));
} catch (err) {
agent.logger.error('springCloud配置文件获取失败!');
throw err;
}
};
/**
* 从临时文件中读取agentWorker保存的远程配置文件,
* 并修改当前项目中的config文件。
* @param app
*/
export const initConfig = (app: EggApplication) => {
const tempConfigFile = path.join(app.baseDir, runtimeFile);
try {
const content = fs.readFileSync(tempConfigFile);
const remoteConfig = JSON.parse(content.toString());
depthSearch(app.config, remoteConfig);
} catch (err) {
app.logger.error('springCloud配置文件读取失败!');
throw err;
}
};
// 项目名/config/config.dev.ts
import { EggAppConfig } from 'egg';
export default () => {
const config: PowerPartial<EggAppConfig> = {};
config.redis = {
client: {
port: '${redis.port}', // 从springCloud配置中取
host: '${redis.host}',
password: '${redis.password}',
db: '${redis.database}',
},
};
config.sequelize = {
dialect: 'postgres', // support: mysql, mariadb, postgres, mssql
database: '${database.name}',
host: '${database.host}',
port: '${database.port}',
username: '${database.username}',
password: '${database.password}',
timezone: '+08:00',
};
return config;
};
# 远程配置文件示例:config.dev.yml
# 数据库的基础配置
database:
host: '127.0.0.1'
port: '1024'
username: 'fuck'
password: 'shit'
name: 'dbname'
# redis的基础配置
redis:
host: '127.0.0.1'
port: '1025'
password: 'fuck'
database: 1