---

前言

试想一下这么一个情况，你想要对一些数据或文件进行批量处理，但是你用的编程语言比较顺手的或者工作使用的编程语言是Typescript或者Javascript，因此想要使用Typescript来实现这些操作。

当然，要想完成这个工作，哪怕你使用python,shell也是可以完成的，但是这里只谈论使用Typescript.

现在就是这个情况，我想要写一个nodejs的TS项目，能够编译我写的代码，并且执行代码，得到我想要的结果。

---

一、明确需求

既然知道了目标，那么就要先明确一下需求。

现在就是这个情况，我想要写一个nodejs的TS项目，能够编译我写的代码，并且执行代码，得到我想要的结果。

从这里可得到以下信息：

1. 项目是使用nodejs，编程语言是Typescript
2. 要能编译ts代码
3. 最后执行ts代码，得到想要的输出结果。

粗略设计

1. 首先定义一个build输出目录，遵从一般的项目标准，使用./dist
2. 定义一个入口文件，ts编译后是js，那么入口文件就是./dist/index.js
3. 使用命令来执行操作，一个build用来编译代码，一个dev来编译和执行。
4. 源码的入口文件是src/index.ts

二、创建项目

使用你的包管理工具（我使用的是pnpm，如果你使用的是npm、yarn或者其他包管理工具，则执行相同的操作即可），初始化一个项目

1. 新建文件夹

mkdir my_project
cd my_project

2. 初始化项目

pnpm init

然后就是输入各种项目信息，创建完毕后当前目录会多出一个package.json文件，内容如下

{
  "name": "my_project",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "keywords": [],
  "author": "",
  "license": "ISC"
}

3. 安装依赖

这里主要是安装typescript的编译依赖和支持nodejs库的一些依赖。

pnpm install typescript @types/node

然后使用npx来初始化一下typescript的配置文件

npx tsc --init

此时当前目录下会多出一个tsconfig.json，这个是全局的ts配置文件，内容如下

{
  "compilerOptions": {
    /* Visit https://aka.ms/tsconfig to read more about this file */

    /* Projects */
    // "incremental": true,                              /* Save .tsbuildinfo files to allow for incremental compilation of projects. */
    // "composite": true,                                /* Enable constraints that allow a TypeScript project to be used with project references. */
    // "tsBuildInfoFile": "./.tsbuildinfo",              /* Specify the path to .tsbuildinfo incremental compilation file. */
    // "disableSourceOfProjectReferenceRedirect": true,  /* Disable preferring source files instead of declaration files when referencing composite projects. */
    // "disableSolutionSearching": true,                 /* Opt a project out of multi-project reference checking when editing. */
    // "disableReferencedProjectLoad": true,             /* Reduce the number of projects loaded automatically by TypeScript. */

    /* Language and Environment */
    "target": "es2016",                                  /* Set the JavaScript language version for emitted JavaScript and include compatible library declarations. */
    // "lib": [],                                        /* Specify a set of bundled library declaration files that describe the target runtime environment. */
    // "jsx": "preserve",                                /* Specify what JSX code is generated. */
    // "experimentalDecorators": true,                   /* Enable experimental support for legacy experimental decorators. */
    // "emitDecoratorMetadata": true,                    /* Emit design-type metadata for decorated declarations in source files. */
    // "jsxFactory": "",                                 /* Specify the JSX factory function used when targeting React JSX emit, e.g. 'React.createElement' or 'h'. */
    // "jsxFragmentFactory": "",                         /* Specify the JSX Fragment reference used for fragments when targeting React JSX emit e.g. 'React.Fragment' or 'Fragment'. */
    // "jsxImportSource": "",                            /* Specify module specifier used to import the JSX factory functions when using 'jsx: react-jsx*'. */
    // "reactNamespace": "",                             /* Specify the object invoked for 'createElement'. This only applies when targeting 'react' JSX emit. */
    // "noLib": true,                                    /* Disable including any library files, including the default lib.d.ts. */
    // "useDefineForClassFields": true,                  /* Emit ECMAScript-standard-compliant class fields. */
    // "moduleDetection": "auto",                        /* Control what method is used to detect module-format JS files. */

    /* Modules */
    "module": "commonjs",                                /* Specify what module code is generated. */
    // "rootDir": "./",                                  /* Specify the root folder within your source files. */
    // "moduleResolution": "node10",                     /* Specify how TypeScript looks up a file from a given module specifier. */
    // "baseUrl": "./",                                  /* Specify the base directory to resolve non-relative module names. */
    // "paths": {},                                      /* Specify a set of entries that re-map imports to additional lookup locations. */
    // "rootDirs": [],                                   /* Allow multiple folders to be treated as one when resolving modules. */
    // "typeRoots": [],                                  /* Specify multiple folders that act like './node_modules/@types'. */
    // "types": [],                                      /* Specify type package names to be included without being referenced in a source file. */
    // "allowUmdGlobalAccess": true,                     /* Allow accessing UMD globals from modules. */
    // "moduleSuffixes": [],                             /* List of file name suffixes to search when resolving a module. */
    // "allowImportingTsExtensions": true,               /* Allow imports to include TypeScript file extensions. Requires '--moduleResolution bundler' and either '--noEmit' or '--emitDeclarationOnly' to be set. */
    // "resolvePackageJsonExports": true,                /* Use the package.json 'exports' field when resolving package imports. */
    // "resolvePackageJsonImports": true,                /* Use the package.json 'imports' field when resolving imports. */
    // "customConditions": [],                           /* Conditions to set in addition to the resolver-specific defaults when resolving imports. */
    // "noUncheckedSideEffectImports": true,             /* Check side effect imports. */
    // "resolveJsonModule": true,                        /* Enable importing .json files. */
    // "allowArbitraryExtensions": true,                 /* Enable importing files with any extension, provided a declaration file is present. */
    // "noResolve": true,                                /* Disallow 'import's, 'require's or '<reference>'s from expanding the number of files TypeScript should add to a project. */

    /* JavaScript Support */
    // "allowJs": true,                                  /* Allow JavaScript files to be a part of your program. Use the 'checkJS' option to get errors from these files. */
    // "checkJs": true,                                  /* Enable error reporting in type-checked JavaScript files. */
    // "maxNodeModuleJsDepth": 1,                        /* Specify the maximum folder depth used for checking JavaScript files from 'node_modules'. Only applicable with 'allowJs'. */

    /* Emit */
    // "declaration": true,                              /* Generate .d.ts files from TypeScript and JavaScript files in your project. */
    // "declarationMap": true,                           /* Create sourcemaps for d.ts files. */
    // "emitDeclarationOnly": true,                      /* Only output d.ts files and not JavaScript files. */
    // "sourceMap": true,                                /* Create source map files for emitted JavaScript files. */
    // "inlineSourceMap": true,                          /* Include sourcemap files inside the emitted JavaScript. */
    // "noEmit": true,                                   /* Disable emitting files from a compilation. */
    // "outFile": "./",                                  /* Specify a file that bundles all outputs into one JavaScript file. If 'declaration' is true, also designates a file that bundles all .d.ts output. */
    // "outDir": "./",                                   /* Specify an output folder for all emitted files. */
    // "removeComments": true,                           /* Disable emitting comments. */
    // "importHelpers": true,                            /* Allow importing helper functions from tslib once per project, instead of including them per-file. */
    // "downlevelIteration": true,                       /* Emit more compliant, but verbose and less performant JavaScript for iteration. */
    // "sourceRoot": "",                                 /* Specify the root path for debuggers to find the reference source code. */
    // "mapRoot": "",                                    /* Specify the location where debugger should locate map files instead of generated locations. */
    // "inlineSources": true,                            /* Include source code in the sourcemaps inside the emitted JavaScript. */
    // "emitBOM": true,                                  /* Emit a UTF-8 Byte Order Mark (BOM) in the beginning of output files. */
    // "newLine": "crlf",                                /* Set the newline character for emitting files. */
    // "stripInternal": true,                            /* Disable emitting declarations that have '@internal' in their JSDoc comments. */
    // "noEmitHelpers": true,                            /* Disable generating custom helper functions like '__extends' in compiled output. */
    // "noEmitOnError": true,                            /* Disable emitting files if any type checking errors are reported. */
    // "preserveConstEnums": true,                       /* Disable erasing 'const enum' declarations in generated code. */
    // "declarationDir": "./",                           /* Specify the output directory for generated declaration files. */

    /* Interop Constraints */
    // "isolatedModules": true,                          /* Ensure that each file can be safely transpiled without relying on other imports. */
    // "verbatimModuleSyntax": true,                     /* Do not transform or elide any imports or exports not marked as type-only, ensuring they are written in the output file's format based on the 'module' setting. */
    // "isolatedDeclarations": true,                     /* Require sufficient annotation on exports so other tools can trivially generate declaration files. */
    // "allowSyntheticDefaultImports": true,             /* Allow 'import x from y' when a module doesn't have a default export. */
    "esModuleInterop": true,                             /* Emit additional JavaScript to ease support for importing CommonJS modules. This enables 'allowSyntheticDefaultImports' for type compatibility. */
    // "preserveSymlinks": true,                         /* Disable resolving symlinks to their realpath. This correlates to the same flag in node. */
    "forceConsistentCasingInFileNames": true,            /* Ensure that casing is correct in imports. */

    /* Type Checking */
    "strict": true,                                      /* Enable all strict type-checking options. */
    // "noImplicitAny": true,                            /* Enable error reporting for expressions and declarations with an implied 'any' type. */
    // "strictNullChecks": true,                         /* When type checking, take into account 'null' and 'undefined'. */
    // "strictFunctionTypes": true,                      /* When assigning functions, check to ensure parameters and the return values are subtype-compatible. */
    // "strictBindCallApply": true,                      /* Check that the arguments for 'bind', 'call', and 'apply' methods match the original function. */
    // "strictPropertyInitialization": true,             /* Check for class properties that are declared but not set in the constructor. */
    // "strictBuiltinIteratorReturn": true,              /* Built-in iterators are instantiated with a 'TReturn' type of 'undefined' instead of 'any'. */
    // "noImplicitThis": true,                           /* Enable error reporting when 'this' is given the type 'any'. */
    // "useUnknownInCatchVariables": true,               /* Default catch clause variables as 'unknown' instead of 'any'. */
    // "alwaysStrict": true,                             /* Ensure 'use strict' is always emitted. */
    // "noUnusedLocals": true,                           /* Enable error reporting when local variables aren't read. */
    // "noUnusedParameters": true,                       /* Raise an error when a function parameter isn't read. */
    // "exactOptionalPropertyTypes": true,               /* Interpret optional property types as written, rather than adding 'undefined'. */
    // "noImplicitReturns": true,                        /* Enable error reporting for codepaths that do not explicitly return in a function. */
    // "noFallthroughCasesInSwitch": true,               /* Enable error reporting for fallthrough cases in switch statements. */
    // "noUncheckedIndexedAccess": true,                 /* Add 'undefined' to a type when accessed using an index. */
    // "noImplicitOverride": true,                       /* Ensure overriding members in derived classes are marked with an override modifier. */
    // "noPropertyAccessFromIndexSignature": true,       /* Enforces using indexed accessors for keys declared using an indexed type. */
    // "allowUnusedLabels": true,                        /* Disable error reporting for unused labels. */
    // "allowUnreachableCode": true,                     /* Disable error reporting for unreachable code. */

    /* Completeness */
    // "skipDefaultLibCheck": true,                      /* Skip type checking .d.ts files that are included with TypeScript. */
    "skipLibCheck": true                                 /* Skip type checking all .d.ts files. */
  }
}

文件中有一些注释，读者可自行观看，我们这里只实现我们的目的。

4. 创建项目结构

接下来创建项目的目录结构，其实最主要的就是创建src目录，然后在src目录下新建个index.ts，至于其他的目录我们还是要用代码去创建。目录结构创建好后，如下图所示

5. 配置ts

ts的配置的话主要是以下内容

1. 保存时编译
2. 语法用最新的
3. 开启sourceMap,方便调试
4. 设置输出目录
5. 设置源码目录
6. 设置包含的ts文件
7. 设置排除的ts文件

如果你有兴趣可以到上面的文档或者ts官方学习一下如何配置，我这里给出完整配置

{
  "compileOnSave": true,
  "compilerOptions": {
    "module": "ES2022",
    "noImplicitAny": true,
    "removeComments": true,
    "preserveConstEnums": true,
    "sourceMap": true,
    "declaration": false,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "target": "ES2023",
    "moduleResolution": "Node",
    "outDir": "./dist",
    "lib": ["ESNext"],
    "esModuleInterop": true,
    "rootDir": "./src"
  },
  "files": ["./src/index.ts"],
  "include": ["src/**/*.ts"],
  "exclude": ["node_modules", "tmp"]
}

6. 配置项目启动命令

按照之前的需求，来编写项目启动命令。

{
  "name": "schemas",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "type": "module",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1",
    "dev": "tsc && node dist/index.js"
  },
  "keywords": [],
  "type": "module",
  "author": "",
  "license": "ISC",
  "dependencies": {
    "typescript": "^5.6.3"
  },
  "devDependencies": {
    "@types/node": "^22.7.5"
  }
}

在工程的package.json中，scripts字段是定义执行的命令的，后面的命令代表两个意思

1. tsc 编译当前项目
2. node dist/index.js执行dist/index.js文件（这是因为编译了以后，输出的就是那个地方的index.js文件，这个在package.json和tsconfig.json中写了的，如果你不理解可以返回去看看）

7. 运行项目

在经过以上操作后，运行以下命令即可看到ts被编译执行了。

pnpm run dev

8. 测试多模块

对于一个ts项目来说，能创建多个ts文件是至关重要的，本来就是想着这么点便利的地方。

此时创建个test.ts文件，里面导出个test方法

const test_hello = (data: string) => {
    return `hello ${data}`;
}

export default test_hello;

然后在index.ts中测试

当前只能以js后缀导入，还是感觉不太舒服的，但是这就需要集成打包工具了，这就很麻烦。