Node文件操作

Node的一些文件操作问题

常用的读取文件的模块：fs

压缩一个文件

使用的是node-archiver

链接：https://github.com/archiverjs/node-archiver

/** * 将目标文件夹打包 * @param dirname 所需要打包文件或文件夹所在的目录 * @param filename 所需打包的文件/目录名称，也是打包后的zip名称 */
 static async zip(dirname:string,filename:string){
    
      let archive = archiver('zip', {
    
          zlib: {
     level: 9 } // 设置压缩级别
       });
       let output = fs.createWriteStream(dirname+`/${
      filename}.zip`);
       console.log("file is zipping!");
       archive.pipe(output);
       archive.directory(dirname+filename+"/",false);   
       await archive.finalize();

       console.log("Util.zip:"+fs.existsSync(dirname+`/${
      filename}.zip`));
}

文件哈希值

使用的是node-crypto

/** * 获取文件哈希值 * @param path * @returns */
 function createFileHash256Sync(path:string):any {
    
    
    //读取一个Buffer
    const buffer = fs.readFileSync(path);
    const fsHash = crypto.createHash('sha256');
 
    fsHash.update(buffer);
    const md5 = fsHash.digest('hex');
    return md5;
 }

使用Form-Data发送压缩文件

使用node-FormData模块

一定记得 import FormData = require(“form-data”); 不然自带的form-data内容只支持blob或者string

传递readStream

// 填充文件
form.append("file",fs.createReadStream(zipPath),{
    
     contentType:"application/octet-stream"
 });


// 如果使用form-data传递json对象，要转换成string进行传递
// 填充参数
form.append("parameters", JSON.stringify({
    
       "filehash":filehash,
       "boardType":config.boardType,
        "compileType":config.compileType
      }),{
    
         contentType:"application/json"
});

封装好之后进行发送时发现node-fetch不支持form-data，request支持的formData格式非常简单不是我们用的那种封装好的from-data，所以这里使用其他方式发送请求。

form-data发送请求

let form = new FormData();
form.append("file", fs.createReadStream(zipPath));
// 向C提交文件数据
form.submit('http://10.33.200.1:8700/api/upload', function(err, res) {
    
      res.resume();
      return res.send({
    
      code:200,
      message:'成功'
   })
});

got发送请求

使用got模块

链接：https://github.com/sindresorhus/got

npm install got

import {
    FormData} from "formdata-node"

// I assume Got >= 12.x is used for this example
import got from "got"

const form = new FormData()

form.set("greeting", "Hello, World!")

const data = await got.post("https://httpbin.org/post", {
    body: form}).json()

console.log(data.form.greeting) // => Hello, World!

编码后使用fetch

import {
    Readable} from "stream"

import {
    FormDataEncoder} from "form-data-encoder"
import {
    FormData} from "formdata-node"

// Note that `node-fetch` >= 3.x have builtin support for spec-compliant FormData, sou you'll only need the `form-data-encoder` if you use `node-fetch` <= 2.x.
import fetch from "node-fetch"

const form = new FormData()

form.set("field", "Some value")

const encoder = new FormDataEncoder(form)

const options = {
    
  method: "post",
  headers: encoder.headers,
  body: Readable.from(encoder)
}

await fetch("https://httpbin.org/post", options)

File对象发送fetch

import {
    FormData, File} from "formdata-node" // You can use `File` from fetch-blob >= 3.x

import fetch from "node-fetch"

const form = new FormData()
const file = new File(["My hovercraft is full of eels"], "file.txt")

form.set("file", file)

await fetch("https://httpbin.org/post", {
    method: "post", body: form})