使用 NodeJs 製作 API SERVER

快速建立API SERVER，可直接進行實務面開發。

環境設定
node: v16.14.2
npm: v8.5.0

創建專案資料夾(api-server) & 專案初始化

mkdir api-server
cd api-server
npm init

安裝相關套件

npm i express
npm i compression      //壓縮回應內文 (express官方推薦)
npm i cors             //跨來源資源共享 (express官方推薦)
npm i body-parser      //HTTP請求解析 (express官方推薦)
npm i cookie-parser    //cookie解析 (express官方推薦)
npm i helmet           //設定http標頭 (express官方推薦)
npm i moment           //日期時間
npm i moment-timezone  //時區
npm i dotenv           //環境變數
npm i http-errors      //處理HTTP Error
npm i require-dir      //增強require應用

參考來源

創建程式資料夾

public 放置前端用靜態資源(.jpg / .png / .css / .js / .html)

mkdir src
mkdir src/public
mkdir src/routes-api
mkdir src/routes-api/api

建立入口點，新增檔案main.js

./src/routes-api/main.js

建立環境變數，新增檔案.env

./.env

修改package.json

//修改前
{
  "name": "api-server",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    ...
  }
}
//修改後
{
  "name": "api-server",
  "version": "1.0.0",
  "scripts": {
    "start": "node ./src/routes-api/main.js"
  },
  "dependencies": {
    ...
  }
}

修改好後，啟動指令就能用了！

npm start

開始編輯主程式

(./src/routes-api/main.js)

//引入套件
require('dotenv').config();
const compression = require('compression');
const createError = require('http-errors');
const express = require('express');
const cors = require('cors');
const dir = require('require-dir');
const bodyParser = require('body-parser');
const cookieParser = require('cookie-parser');
const moment = require('moment');
const tz = require('moment-timezone');
const path = require('path');
const http = require('http');
const helmet = require('helmet');
const app = express();
//讀取環境變數
moment.tz.setDefault(process.env['DEFAULT_TIME_ZOME']);
const MAIN_NODE_PORT = process.env['MAIN_NODE_PORT'];
const MAIN_API_TIMEOUT = parseInt(process.env['MAIN_API_TIMEOUT']);
let server = null;
//各套件初始化
app.use(cors());
app.use(helmet({
    frameguard: true,
    xssFilter: true,
    noSniff: true
}));
app.use(bodyParser.json({
    limit: '10mb',
    verify: function (req, res, buf, encoding) {
        req.rawBody = buf;
    },
}));
app.use(bodyParser.urlencoded({ extended: false, }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, '../public'))); //指定靜態目錄裝載路徑
app.use(compression());
//========== 實作API開始 ====================
function access_log(req, res, next) {
    const dd = Date.now();
    const url = req.path;
    const remoteIP = (req.headers['x-forwarded-for'] || req.connection.remoteAddress || req.ip || '0.0.0.0');
    console.debug(`req from ${req.method.toUpperCase()} ${url} ${JSON.stringify(req.body)}, remoteIP:${remoteIP}`);
    res.once('finish', () => {
        console.debug(`response from ${req.method.toUpperCase()} ${url} ${JSON.stringify(req.body)} ${res.statusCode}, cost:${Date.now() - dd}`);
    })
    next();
}
//呼叫API, 直接返回結果
Object.keys(dir(`./api`)).forEach((controller) => {
    require(`./api/${controller}`)(app, [access_log]);
});
//查無API, 返回404
app.use(function (req, res, next) {
    next(createError(404));
});
app.use(function (err, req, res, next) {
    // set locals, only providing error in development
    res.locals.message = err.message;
    res.locals.error = req.app.get('env') === 'development' ? err : {};
// render the error page
    res.status(err.status || 500);
    res.json({ code: err.status, message: res.locals.message });
});
//========== 實作API結束 ====================
//程式進入點
(async function start() {
    try {
        //連線db
        //....
//啟動express
        server = http.createServer(app);
        server.on('error', onServerErrorHandle);
        server.setTimeout(MAIN_API_TIMEOUT);
        server.listen(MAIN_NODE_PORT);
console.log('api server pid:', process.pid, 'listen:', MAIN_NODE_PORT);
    } catch (err) {
        console.error(err);
    }
})();
//啟動express錯誤,事件處理函式
function onServerErrorHandle(error) {
    try {
        if (error.syscall !== 'listen') throw error;
        let bind = typeof MAIN_NODE_PORT === 'string' ? 'Pipe ' + MAIN_NODE_PORT : 'Port ' + MAIN_NODE_PORT;
        switch (error.code) {
            case 'EACCES':
                console.log(bind + ' requires elevated privileges (use sudo)');
                process.exit(1);
                break;
            case 'EADDRINUSE':
                console.log(bind + ' is already in use');
                process.exit(1);
                break;
            default:
                throw error;
        }
    } catch (err) {
        console.error(err);
    }
}
//偵聽nodejs, 進程終止信號
process.once('SIGINT', () => {
    server && server.close(() => {
        console.log('process terminated');
        process.exit(0);
    })
});

編輯環境變數

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(./.env)

MAIN_NODE_PORT=8081 #啟動後的API Server PORT
MAIN_API_TIMEOUT=60000
DEFAULT_TIME_ZOME=Etc/UTC #啟動後的API Server時區

主程式完成！

接下來~

撰寫API，在指定目錄下，新增JS檔案!

(一個API，一份JS檔案)

GET API 範本

./src/routes-api/api/01–01_get-helloworld.js

const express = require('express');
module.exports = function (app, common_middleware = []) {
    const router = express.Router();
    app.use(router);
/**
     * GET API
     */
    router.get(['/test/get-helloworld'], [...common_middleware], async (req, res, next) => {
        try {
            const { name } = req.query; //req.query
            return res.json({ code: 0, data: name });
        } catch (err) {
            console.error(err);
            return res.status(500).json(
                { code: 500, message: `something wrong` }
            );
        }
    });
}

POST API 範本

./src/routes-api/api/01–02_post-helloworld.js

const express = require('express');
module.exports = function (app, common_middleware = []) {
    const router = express.Router();
    app.use(router);
/**
     * POST API
     */
    router.post(['/test/post-helloworld'], [...common_middleware], async (req, res, next) => {
        try {
            const { name } = req.body; //req.body
            return res.json({ code: 0, data: name });
        } catch (err) {
            console.error(err);
            return res.status(500).json(
                { code: 500, message: `something wrong` }
            );
        }
    });
}

使用 POSTMAN 進行 API 測試

** 完成 **

最後的，專案資料夾結構~

專案下載Github位置

使用方式

npm i
npm start