使用nodejs分离html文件里的js和css详解

// extract-js-css

// import fs from 'fs'

var fs = require('fs')

// import csscomb from 'csscomb'

// var csscomb = require('csscomb')

// var comb = new csscomb('zen');

// console.log(comb)

 

// 删除文件

const deleteFile = (path)=>{

  return new Promise(resolve => {

    fs.unlink(path, (err) => {

      if (err) {

        console.log(err)

        return

      };

      console.log(`已成功删除 ${path}文件`);

      resolve()

    });

  })

}

 

// 删除文件夹

const deleteDir = async (path)=>{

  let _files = await new Promise (resolve => {

    fs.readdir(path, (err,files) => {

      if (err) {

        console.log(err)

      };

      console.log(`已成功读取 ${path} 文件夹`);

      resolve(files)

    })

  })

 

  if(_files && _files.length) {

    for(let i =0;i<_files.length;i++) {

      // console.log(_files[i],'innnnnn')

      await deleteFile('./test/'+ _files[i])

    }

  }

  // console.log('delete hou')

 

  await new Promise(resolve => {

    fs.rmdir(path, (err) => {

      if (err) {

        console.log(err)

      };

      console.log(`已成功删除空 ${path}文件夹`);

      resolve()

    })

  });

}

const emptyDir = (path) => {

  return new Promise(resolve => {

    fs.rmdir(path, (err) => {

      if (err) {

        console.log(err)

      };

      console.log(`已成功删除空 ${path}文件夹`);

      resolve()

    })

  })

}

// 新建文件夹

/**

 * 

 */

const mkdirTest = ()=>{

  return new Promise(resolve => {

    fs.mkdir('./test', { recursive: true }, (err, data)=>{

      if (err) {

        console.log(err)

      };

      console.log('新建文件夹成功')

      resolve()

    })

  })

}

 

// 读取html 内容

/**

 * 

 */

const readHtml = ()=>{

  return new Promise(resolve => {

    fs.readFile('./test.html', 'utf-8', (err, data)=>{

      if(err) {

        throw Error(err)

      }

      console.log('test.html 读取成功！--NO1')

      resolve(data)

    })

  })

}

 

// 写入css 和js

/**

 * 向文件中追加内容

 * @param {是文件名字} path 

 * @param {写入文件的内容} data 

 * @param {文件类型} type 

 * @author erlinger

 * @time 

 */

const appendFile = (path, data, type) => {

  return new Promise(resolve => {

    fs.appendFile(path, data, (err) => {

      if (err) {

        console.log(err)

      };

      console.log(`${type}数据已追加到文件`);

      resolve()

    });

  })

}

// 写一个html

const writeHtml = (path, data) => {

  return new Promise(resolve => {

    fs.writeFile(path, data, (err) =>{

      if(err) {

        console.log('err', err)

        return

      }

      console.log(`${path} 写入成功，功能结束!`);

      resolve() // 必须resolve 。不然 promise 就到此为止，调用该方法后面的代码将不执行

    })

  })

}

 

// 插件 方法入口

(async ()=>{

  console.log('==========================game-start=============================');

  await deleteDir('./test');

  console.log('我应该是等---删除文件夹后---才出现')

 

  await mkdirTest();

  console.log('我应该是在---文件夹新建成功---后出现！');

 

  let cssReg = /<style>[\s|\S]*?<\/style>/ig;

  let jsReg = /<script>[\s|\S]*?<\/script>/ig;

  let allStyleReg = /<\/style>[\s|\S]*?<style>/ig;

  let allScriptReg = /<\/script>[\s|\S]*?<script>/ig;

  let cssLink = '<link rel="stylesheet" href="./test.css" rel="external nofollow" >';

  let jsrc = '<script src="./test.js"></script>';

  let styleCollection, scriptColletion;

  let cssContent = '', jsContent = '', htmlContentStr = '';

 

  let originContent = await readHtml();

  styleCollection = originContent.match(cssReg);

  scriptColletion = originContent.match(jsReg);

   

  // 处理 css

  for (let i =0;i<styleCollection.length;i++) {

    cssContent += JSON.stringify(styleCollection[i]);

  }

 

  cssContent = cssContent.replace(/<style>/g,'').replace(/<\/style>/g, '').replace(/("")/g,'')

   

  for (let i =0;i<scriptColletion.length;i++) {

    jsContent += JSON.stringify(scriptColletion[i]);

  }

   

  jsContent = jsContent.replace(/<script>/g,'').replace(/<\/script>/g, '')

  .replace(/<\/script>"*<script>/g, '').replace(/("")/g,'')

   

  await appendFile('./test/test.css', JSON.parse(cssContent), 'css');

  console.log('我应该是在---css写入成功---后出现！');

 

  await appendFile('./test/test.js', JSON.parse(jsContent), 'js');

  console.log('我应该是在---js写入成功---后出现！');

 

  htmlContentStr = originContent

  .replace(allStyleReg, '')

  .replace(cssReg, cssLink)

  .replace(allScriptReg, '')

  .replace(jsReg, jsrc);

  console.log('copyTest.html 文本已经格式化，准备写入');

  await writeHtml('./test/copyTest.html', htmlContentStr);

 

  console.log('==========================game-over=============================');

})()

node extract-js-css