zhimeng/app/mw/mw_request_cache.go

package mw

import (
	"applet/app/e"
	"applet/app/md"
	"applet/app/utils"
	"applet/app/utils/cache"
	"bytes"
	"fmt"
	"github.com/gin-gonic/gin"
	"io/ioutil"
)

//自己实现一个type gin.ResponseWriter interface
type responseWriter struct {
	gin.ResponseWriter
	b *bytes.Buffer
}

//重写Write([]byte) (int, error)
func (w responseWriter) Write(b []byte) (int, error) {
	//向一个bytes.buffer中再写一份数据
	w.b.Write(b)
	//完成gin.Context.Writer.Write()原有功能
	return w.ResponseWriter.Write(b)
}

// RequestCache is cache middleware
func RequestCache(c *gin.Context) {
	tempMasterId, _ := c.Get("master_id")
	masterId := tempMasterId.(string)
	uri := c.Request.RequestURI
	md5Params := dealBodyParams(c)
	cacheKey := fmt.Sprintf(md.ZhimengDataRequestCacheKey, masterId, uri, md5Params)
	//自己实现一个type gin.ResponseWriter
	writer := responseWriter{
		c.Writer,
		bytes.NewBuffer([]byte{}),
	}
	isUse, _ := cache.GetInt(md.ZhimengIsUseCacheKey)
	var res = map[string]interface{}{}
	cache.GetJson(cacheKey, &res)
	if res["data"] != nil && isUse == 1 {
		e.OutSuc(c, res["data"], nil)
		return
	}
	c.Writer = writer
	c.Next()
}

func dealBodyParams(c *gin.Context) (md5Params string) {
	body, err := c.GetRawData()
	if err != nil {
		panic(err)
	}
	fmt.Println(">>>>>>>>>>string<<<<<<<<<<<", string(body))
	md5Params = utils.Md5(string(body))
	//TODO::把读过的字节流重新放到body
	c.Request.Body = ioutil.NopCloser(bytes.NewBuffer(body))
	return
}