gin tar gz on the fly sample

main.go

package main

import (
	"archive/tar"
	"bufio"
	"bytes"
	"compress/gzip"
	"fmt"
	"io"
	"log"
	"net/http"
	"os"
	"path/filepath"
	"regexp"

	"github.com/gin-gonic/gin"
)

var db = make(map[string]string)

func setupRouter() *gin.Engine {
	// Disable Console Color
	// gin.DisableConsoleColor()
	r := gin.Default()

	// Ping test
	r.GET("/ping", func(c *gin.Context) {
		c.String(http.StatusOK, "pong")
	})

	// Get user value
	r.GET("/buckets/:ID", func(ctx *gin.Context) {

		invalidSymbols := regexp.MustCompile("[^a-zA-Z0-9-_]")
		bucketID := invalidSymbols.ReplaceAllString(ctx.Param("ID"), "")

		fmt.Printf(fmt.Sprintf("Using bucket: %s", bucketID))

		if _, err := os.Stat("/tmp/bucket/" + bucketID); os.IsNotExist(err) {
			ctx.JSON(http.StatusNotFound, "Bucket doesn't exist.")
			return
		}
		fmt.Printf("Using bucket path")

		var tarOutput bytes.Buffer
		tarWriter := tar.NewWriter(&tarOutput)

		err := filepath.Walk("/tmp/bucket/"+bucketID, func(path string, info os.FileInfo, err error) error {
			if err != nil {
				fmt.Println(err)
				return err
			}
			fmt.Printf("dir: %v: name: %s\n", info.IsDir(), path)

			if !info.IsDir() {
				file, _ := os.Open(path)

				hdr, err := tar.FileInfoHeader(info, path)
				if err != nil {
					panic(err)
				}
				if err := tarWriter.WriteHeader(hdr); err != nil {
					log.Fatal(err)
				}
				if _, err = io.Copy(tarWriter, file); err != nil {
					log.Fatal(err)
				}
			}

			return nil
		})

		if err := tarWriter.Close(); err != nil {
			fmt.Println(err)
		}

		fmt.Printf("ADDED FILES done")

		if err != nil {
			fmt.Println(err)
		}

		fromTar := bufio.NewReader(&tarOutput)

		ctx.Writer.Header().Set("Content-Disposition", fmt.Sprintf("attachment; filename=\"%s\"", bucketID+".tar.gz"))

		gzWriter := gzip.NewWriter(ctx.Writer)
		defer gzWriter.Close()

		gzWriter.Name = bucketID + ".tar.gz"
		gzWriter.Comment = "MMMMMMM bucket data archive"
		if _, err := io.Copy(gzWriter, fromTar); err != nil {
			fmt.Println(err)
		}
	})

	return r
}

func main() {
	r := setupRouter()
	// Listen and Server in 0.0.0.0:8080
	r.Run(":8080")
}