关于javascript:从零搭建-Nodejs-企业级-Web-服务器十二远程调用

37次阅读

共计 7286 个字符，预计需要花费 19 分钟才能阅读完成。

对于近程调用

近程调用（简称 RPC）次要是指服务器或集群之间对处理过程的调用。通过近程调用能够买通不同零碎之间的数据与性能，或是抽离与建设公共的逻辑对立提供服务。近程调用的两端也称为近程调用的客户端与服务端，个别是多对多的关系，须要引入注册与发现机制进行治理，下图为最常见实际：

治理机制通常是就地取材的，能够基于 ZooKeeper 建设，本章不再开展。

gRPC

gPRC 是谷歌开源的一款跨语言高性能的 RPC 框架，底层应用 protobuf 进行数据交换，已在谷歌、奈非、思科等企业大规模利用。以下为 gRPC 的调用过程，客户端先进行 DNS 解析，再依据解析后果直连服务端或向负载平衡 / 治理服务获取服务端信息再连贯：

本章将基于上一章已实现的工程 host1-tech/nodejs-server-examples – 11-schedule 退出近程调用性能实现一个简略音讯的输出与输入，当初到工程根目录装置 grpc 相干模块：

$ yarn add @grpc/grpc-js @grpc/proto-loader # 本地装置 @grpc/grpc-js、@grpc/proto-loader
# ...
info Direct dependencies
├─ @grpc/grpc-js@1.1.3
└─ @grpc/proto-loader@0.5.5
# ...

加上近程调用

通过 .proto 文件定义近程接口并写入基于该定义的 gRPC 客户端与服务端：

$ mkdir src/rpc       # 新建 src/rpc 寄存近程调用逻辑

$ mkdir src/rpc/echo  # 新建 src/rpc/echo

$ tree src -L 1       # 展现 src 目录内容构造
src
├── config
├── controllers
├── middlewares
├── models
├── moulds
├── rpc
├── schedules
├── server.js
├── services
└── utils
// src/rpc/echo/def.proto
syntax = "proto3";

service Echo {rpc Get(EchoRequest) returns (EchoResponse) {}}

message EchoRequest {string message = 1;}

message EchoResponse {string message = 1;}
// src/rpc/echo/client.js
const {resolve} = require('path');
const {promisify} = require('util');
const protoLoader = require('@grpc/proto-loader');
const grpc = require('@grpc/grpc-js');
const {rpc} = require('../../config');

class EchoClient {
  grpcClient;

  async init() {
    const grpcObject = grpc.loadPackageDefinition(await protoLoader.load(resolve(__dirname, 'def.proto'))
    );

    this.grpcClient = new grpcObject.Echo(`${rpc.domain}:${rpc.port}`,
      grpc.credentials.createInsecure());
  }

  get = async ({s, logger}) => {const { grpcClient} = this;

    const {message} = await promisify(grpcClient.get.bind(grpcClient, { message: s})
    )();

    logger.info('Echo/Get Invoked');

    return {message};
  };
}

let client;
module.exports = async () => {if (!client) {client = new EchoClient();
    await client.init();}
  return client;
};
// src/rpc/echo/server.js
const {resolve} = require('path');
const {callbackify} = require('util');
const protoLoader = require('@grpc/proto-loader');
const grpc = require('@grpc/grpc-js');

class EchoServer {
  grpcServer;

  async init() {
    const grpcObject = grpc.loadPackageDefinition(await protoLoader.load(resolve(__dirname, 'def.proto'))
    );

    this.grpcServer.addService(grpcObject.Echo.service, this);
  }

  get = callbackify(async (call) => {const { message} = call.request;
    return {message};
  });
}

let server;
module.exports = async (grpcServer) => {if (!server) {server = new EchoServer();
    Object.assign(server, { grpcServer});
    await server.init();}
  return server;
};
// src/config/index.js
// ...
const config = {
  // 默认配置
  default: {
    // ...
+    
+    rpc: {
+      domain: 'localhost',
+      port: process.env.PORT_RPC || 9001,
+    },
  },
  // ...
};
// ...

开启 gRPC 日志输入并初始化：

# .env
LOG_LEVEL='debug'
+
+GRPC_TRACE='all'
+GRPC_VERBOSITY='DEBUG'
// src/utils/logger.js
// ...
+const GRPC_LOGGER_REGEXP = /^.+Z\s+\|\s+/;
+
+function grpcLogger(logger, level = 'debug') {+  const verbosities = ['debug', 'info', 'error'];
+
+  return {+    error(severity, message) {+      if (typeof severity != 'number') {
+        message = severity;
+        severity = 0;
+      }
+
+      if (typeof message != 'string') {+        message = String(message || '');
+      }
+
+      logger[verbosities[severity] || level](+        message.replace(GRPC_LOGGER_REGEXP, '')
+      );
+    },
+  };
+}
+
module.exports = logger;

-Object.assign(module.exports, { logging});
+Object.assign(module.exports, { logging, grpcLogger});
// src/rpc/index.js
const {promisify} = require('util');
const grpc = require('@grpc/grpc-js');
const {rpc} = require('../config');
const logger = require('../utils/logger');
const echoClient = require('./echo/client');
const echoServer = require('./echo/server');
const {grpcLogger} = logger;

module.exports = async function initRpc() {grpc.setLogger(grpcLogger(logger.child({ type: 'rpc'}), 'debug'));

  // init rpc servers
  const grpcServer = new grpc.Server();
  await echoServer(grpcServer);

  await promisify(grpcServer.bindAsync.bind(grpcServer))(`0.0.0.0:${rpc.port}`,
    grpc.ServerCredentials.createInsecure());
  grpcServer.start();

  // init rpc clients
  await echoClient();};
// src/server.js
const express = require('express');
const {resolve} = require('path');
const {promisify} = require('util');
const initMiddlewares = require('./middlewares');
const initControllers = require('./controllers');
const initSchedules = require('./schedules');
+const initRpc = require('./rpc');
const logger = require('./utils/logger');

const server = express();
const port = parseInt(process.env.PORT || '9000');
const publicDir = resolve('public');
const mouldsDir = resolve('src/moulds');

async function bootstrap() {+  await initRpc();
  server.use(await initMiddlewares());
  server.use(express.static(publicDir));
  server.use('/moulds', express.static(mouldsDir));
  server.use(await initControllers());
  server.use(errorHandler);
  await initSchedules();
  await promisify(server.listen.bind(server, port))();
  logger.info(`> Started on port ${port}`);
}
// ...

增加 gRPC 客户端 logger 与管制层入口：

// src/middlewares/trace.js
const {v4: uuid} = require('uuid');
const morgan = require('morgan');
const onFinished = require('on-finished');
const logger = require('../utils/logger');
const {logging} = logger;

module.exports = function traceMiddleware() {
  return [morgan('common', { skip: () => true }),
    (req, res, next) => {req.uuid = uuid();
      req.logger = logger.child({uuid: req.uuid});
      req.loggerSql = req.logger.child({type: 'sql'});
      req.logging = logging(req.loggerSql, 'info');
+      req.loggerRpc = req.logger.child({type: 'rpc'});

      onFinished(res, () => {// ...});

      next();},
  ];
};
// src/controllers/echo.js
const {Router} = require('express');
const cc = require('../utils/cc');
const rpcEchoClient = require('../rpc/echo/client');

class EchoController {
  rpcEchoClient;

  async init() {this.rpcEchoClient = await rpcEchoClient();

    const router = Router();
    router.get('/', this.get);
    return router;
  }

  get = cc(async (req, res) => {const { s = ''} = req.query;
    const message = await this.rpcEchoClient.get({s, logger: req.loggerRpc});
    res.send({success: true, message});
  });
}

module.exports = async () => {const c = new EchoController();
  return await c.init();};
// src/controllers/index.js
const {Router} = require('express');
const shopController = require('./shop');
const chaosController = require('./chaos');
const healthController = require('./health');
const loginController = require('./login');
const csrfController = require('./csrf');
+const echoController = require('./echo');

module.exports = async function initControllers() {const router = Router();
  router.use('/api/shop', await shopController());
  router.use('/api/chaos', await chaosController());
  router.use('/api/health', await healthController());
  router.use('/api/login', await loginController());
  router.use('/api/csrf', await csrfController());
+  router.use('/api/echo', await echoController());
  return router;
};

拜访 http://localhost:9000/api/echo?s=Hello%20RPC 即可看到成果：

同时在命令行可能看到充沛的 gRPC 日志：

# ...
08:20:52.320Z DEBUG 12-rpc: dns_resolver | Resolver constructed for target dns:0.0.0.0:9001 (type=rpc)
08:20:52.321Z DEBUG 12-rpc: dns_resolver | Resolution update requested for target dns:0.0.0.0:9001 (type=rpc)
08:20:52.321Z DEBUG 12-rpc: dns_resolver | Returning IP address for target dns:0.0.0.0:9001 (type=rpc)
08:20:52.322Z DEBUG 12-rpc: server | Attempting to bind 0.0.0.0:9001 (type=rpc)
08:20:52.324Z DEBUG 12-rpc: server | Successfully bound 0.0.0.0:9001 (type=rpc)
08:20:52.327Z DEBUG 12-rpc: resolving_load_balancer | dns:localhost:9001 IDLE -> IDLE (type=rpc)
08:20:52.327Z DEBUG 12-rpc: connectivity_state | dns:localhost:9001 IDLE -> IDLE (type=rpc)
08:20:52.327Z DEBUG 12-rpc: dns_resolver | Resolver constructed for target dns:localhost:9001 (type=rpc)
# ...

本章源码

host1-tech/nodejs-server-examples – 12-rpc

更多浏览

从零搭建 Node.js 企业级 Web 服务器（零）：动态服务
从零搭建 Node.js 企业级 Web 服务器（一）：接口与分层
从零搭建 Node.js 企业级 Web 服务器（二）：校验
从零搭建 Node.js 企业级 Web 服务器（三）：中间件
从零搭建 Node.js 企业级 Web 服务器（四）：异样解决
从零搭建 Node.js 企业级 Web 服务器（五）：数据库拜访
从零搭建 Node.js 企业级 Web 服务器（六）：会话
从零搭建 Node.js 企业级 Web 服务器（七）：认证登录
从零搭建 Node.js 企业级 Web 服务器（八）：网络安全
从零搭建 Node.js 企业级 Web 服务器（九）：配置项
从零搭建 Node.js 企业级 Web 服务器（十）：日志
从零搭建 Node.js 企业级 Web 服务器（十一）：定时工作
从零搭建 Node.js 企业级 Web 服务器（十二）：近程调用

正文完
javascript
发表至： javascript
2020-08-04
 0
关于javascript:物联网与数据可视化的结合农业领域中的智慧大棚系统
关于javascript:前端知识点提炼五月份
关于javascript:常见跨域解决办法二CORSpostMessage
前端常见面试题总结