koa test2

async function run(){
    const koa = require('koa')
    const Router = require('koa-router')
    const Static = require('koa-static-cache')
    const mysql=require('mysql2/promise')
    const bodyparser=require('koa-bodyparser')
    const koaBody=require('koa-body')
    const multiparty=require('koa2-multiparty')
    const path=require('path')
    const fs=require('fs')

    const app = new koa()
    const router = new Router()
    app.use(async (ctx, next)=> {
        ctx.set('Access-Control-Allow-Origin', '*');
        ctx.set('Access-Control-Allow-Headers', 'Content-Type, Content-Length, Authorization, Accept, X-Requested-With , yourHeaderFeild');
        ctx.set('Access-Control-Allow-Methods', 'PUT, POST, GET, DELETE, OPTIONS');
        if (ctx.method == 'OPTIONS') {
          ctx.body = 200;
        } else {
          await next();
        }
      });
    app.use(bodyparser())
//文件上传
    app.use(koaBody({
        multiparty:true,
        encoding:'gzip',
        formidable:{
            maxFieldsSize:20*1024*1024,//设置文件上传最大大小
        },
        keepExtensions:true //保存后缀
    }))


    app.use(
        Static('./static'), {
        prefix: '/static',
        gzip: true
    }
    )
    //连接数据库
    const connection=await mysql.createConnection({
        host:"127.0.0.1",
        user:"uniapp",
        password:'123456',
        database:'uniapp'
    })

    // router.get('/test',async ctx=>{
    //     // ctx.body='hello'
    //     let [data]=await connection.query("SELECT * FROM videos")
    //     ctx.body=data
    // })
    //文件上传接口
    router.post('/upload',multiparty(),async ctx=>{
        //获取formdata中的数据
        const {name,type}=ctx.req.body
        //文件名及文件路径
        const file=ctx.req.files.file
        const path=ctx.req.files.file.path

        //创建文件的输入流
        const fileReader=fs.createReadStream(path)
        //定义文件存储路径
        const fileDir=`${__dirname}/static/${type}`
        const filepath=`${fileDir}/${name}`
        //创建文件输出流
        const fileWrite=fs.createWriteStream(filepath)
        //写入文件数据
        fileReader.pipe(fileWrite)
        ctx.body={
            code:1,
            data:'上传成功'
        }
    })

    router.get('/video',async ctx=>{
        let [data]=await connection.query("SELECT * FROM videos LIMIT 0,3")
        ctx.body={
            code:1,
            data
        }
    })

    //通过id查询用户信息接口
    router.get('/user',async ctx=>{
        let [data]=await connection.query("SELECT * FROM user WHERE id=1")
        ctx.body={
            code:1,
            data
        }
    })

    //修改用户信息接口
    router.post('/user',async ctx=>{
        const {data,columnName}=ctx.request.body
         let query=""
        switch (columnName){
              case userName:query="UPDATE user SET userName =? WHERE id=1";
              break;
              case userId:query="UPDATE user SET userId =? WHERE id=1";
              break;
              case redirect:query="UPDATE user SET redirect =? WHERE id=1";
              break;
              case school:query="UPDATE user SET school =? WHERE id=1";
              break;
              case sex:query="UPDATE user SET sex =? WHERE id=1";
              break;
              case birthday:query="UPDATE user SET birthday =? WHERE id=1";
              break;
              case city :query="UPDATE user SET city =? WHERE id=1";
              break;
              default:
                  ctx.body='错误'
        }
        // let query="UPDATE user SET userName =? WHERE id=1"
        value=[data]
        let [lr]=await connection.query(query,value)
        if(lr.affectedRows>0){
            ctx.body={
                code:1,
                data:'成功'
            }
        }else{
            ctx.body={
                code:0,
                data:'失败'
            }
        }
    })
    app.use(router.routes())
    app.listen(8080)
}

run()