如何创建/配置 NodeTS（TypeScript NodeJS）项目？

Question

我正在尝试创建并运行一个简单的 TypeScript NodeJS 项目。 以下是我的代码：

服务器.ts：

import express from 'express';

const app = express();
const PORT = 3000;

app.listen(PORT , ()=>{
    console.log('Server is listening on port $PORT');
});

tsconfig.json：

{
  "compilerOptions": {
  
    "target": "esnext",                                  /* Set the JavaScript language version for emitted JavaScript and include compatible library declarations. */

    "module": "commonjs",                                /* Specify what module code is generated. */
    "rootDir": "./src",                                  /* Specify the root folder within your source files. */
    "moduleResolution": "node",                       /* Specify how TypeScript looks up a file from a given module specifier. */

    "outDir": "./build",                                   /* Specify an output folder for all emitted files. */
    "esModuleInterop": true,                             /* Emit additional JavaScript to ease support for importing CommonJS modules. This enables 'allowSyntheticDefaultImports' for type compatibility. */
    "forceConsistentCasingInFileNames": true,            /* Ensure that casing is correct in imports. */

    "strict": true,                                      /* Enable all strict type-checking options. */
    "skipLibCheck": true                                 /* Skip type checking all .d.ts files. */
  }
}

package.json：

{
  "name": "back",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "nodemon build/server.js"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@types/express": "^4.17.13",
    "express": "^4.18.1",
    "mongoose": "^6.5.0",
    "nodemon": "^2.0.19"
  }
}

当我尝试npm start ，我收到以下错误消息：

> back@1.0.0 start       
> nodemon build/server.js

[nodemon] 2.0.19
[nodemon] to restart at any time, enter `rs`      
[nodemon] watching path(s): *.*
[nodemon] watching extensions: js,mjs,json        
[nodemon] starting `node build/server.js index.js`
node:internal/modules/cjs/loader:936
  throw err;
  ^

Error: Cannot find module 'C:\Users\A\\Test\back\index.js'
    at Function.Module._resolveFilename (node:internal/modules/cjs/loader:933:15)
    at Function.Module._load (node:internal/modules/cjs/loader:778:27)
    at Function.executeUserEntryPoint [as runMain] (node:internal/modules/run_main:77:12)
    at node:internal/main/run_main_module:17:47 {
  code: 'MODULE_NOT_FOUND',
  requireStack: []
}
[nodemon] app crashed - waiting for file changes before starting...

Answer 1

您已在package.json入口文件设置为index.js ，因此nodemon正在尝试同时运行server.js和index.js ，但它们不存在。 解决此问题的最简单方法 - 例如，假设您已经使用tsc编译了 TS 文件 - 是将package.json中的入口点main更改为build/server.js 。

所以你必须做的：

1. 安装typescript以便能够转译您的代码：

npm install typescript

2. Before running npm start , you have to make sure your code is transpiled, that is, "compiled" to vanilla JavaScript, so add this script to your package.json :

{
  "scripts": {
    // ...
    "build": "tsc"
  }
}

3. 将package.json中的main更新为build/server.js 。
4. 运行npm run build然后最后npm start 。

完毕。 您的服务器将启动

---

我在答案更新之前的提示：

此外，为nodemon ( nodemon.json ) 创建一个配置文件将使您的事情变得更简单，请查看文档。

最后，如果您是新手，我建议您看一下这个repo中的一些现成的tsconfig基础，特别是Node 16的这个。

Answer 2

我修改了我的tsconfig.json文件，如下所示：

{
  "name": "back",
  "version": "1.0.0",
  "description": "",
  "main": "server.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "start": "nodemon src/server.ts"
  },
  "author": "",
  "license": "ISC",
  "dependencies": {
    "@types/express": "^4.17.13",
    "express": "^4.18.1",
    "mongoose": "^6.5.0"
  },
  "devDependencies": {
    "nodemon": "^2.0.19",
    "ts-node-dev": "^2.0.0",
    "typescript": "^4.7.4"
  }
}

创建的更改在这些行中：

"main": "index.js"到"main": "server.js"

"start": "nodemon build/server.js"到"start": "nodemon src/server.ts"