// main.go
package main
import (
"fmt"
"log"
"time"
"github.com/gin-contrib/gzip"
"github.com/gin-gonic/gin"
)
func useGzip(engine *gin.Engine) {
engine.Use(gzip.Gzip(gzip.DefaultCompression))
}
func main() {
log.SetFlags(log.LstdFlags | log.Lshortfile)
engine := gin.New()
// engine.Use(gzip.Gzip(gzip.DefaultCompression)) //如果需要开启gzip压缩，取消这一行的注释
engine.Handle("POST", "/query", downloadFile)
engine.Handle("GET", "/", homepage)
engine.Run(":8080")
}
func downloadFile(ctx *gin.Context) {
reqData, has := ctx.GetPostForm("json")
if !has {
ctx.Data(400, "text/plain","not found json form data")
return
}
// 此处省略查询的业务逻辑
// todo:
// 下面开始下载的准备
ctx.Writer.WriteHeader(200)
ctx.Header("Content-Type", "text/plain; charset=utf-8")
ctx.Header("Transfer-Encoding", "chunked") // 告诉浏览器，分段的流式的输出数据
// ctx.Header("Content-Encoding", "gzip") // 输出不是gzip内容，又加上这个头，浏览器会拒收。这里是个实验，不要加这行代码
now := time.Now()
fileName := now.Format("20060102_150405.csv")
ctx.Header("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s\"", fileName)) // 设置下载的文件名
ctx.Writer.WriteHeaderNow()
// 下面模拟一个周期非常长的数据处理和下载过程
for i := 0; i < 100; i++ {
ctx.Writer.WriteString("\"")
ctx.Writer.WriteString(str)
ctx.Writer.WriteString("\"\t")
ctx.Writer.WriteString("\"")
ctx.Writer.WriteString(time.Now().Format("2006-01-02 15:04:05"))
ctx.Writer.WriteString("\"\n")
ctx.Writer.Flush() // 产生一定的数据后， flush到浏览器端
time.Sleep(time.Duration(500) * time.Millisecond)
}
}
func homepage(ctx *gin.Context) {
ctx.Header("Content-Type", "text/html")
ctx.Writer.WriteString(`
<html>
<body>
open window and to download:
<a href="javascript:download()">download</a>
<script>
function download(){
var handle = window.open("about:blank", "my_download_window");
document.forms[0].target = "my_download_window";
document.forms[0].json.value="ahfu test";
document.forms[0].submit();
}
</script>
<form action="/query" method="POST" enctype="multipart/form-data">
<input type="hidden" name="json" value=""/>
</form>
</body>
</html>
`)
}
标签：WriteString,Writer,ctx,golang,gzip,download,gin From： https://www.cnblogs.com/lqq2314/p/16977757.html