Golang实现图片缩放服务器

package main
import (
    "fmt"
    "graphics"
    "image"
    "image/png"
    "log"
    "net/http"
    "os"
    "strconv"
    "strings"
)
func main() {
    http.HandleFunc("/", doImageHandler)
    http.ListenAndServe("127.0.0.1:6789", nil)
}
func doImageHandler(w http.ResponseWriter, r *http.Request) {
    fmt.Printf("%q\n", strings.Split(r.URL.Path, "/"))
    url := strings.Split(r.URL.Path, "/")
    if len(url) != 3 {
        return
    }
    newdx, uerr := strconv.Atoi(url[1])
    if uerr != nil {
        log.Fatal(uerr)
    }
    src, err := LoadImage(url[2])
    bound := src.Bounds()
    dx := bound.Dx()
    dy := bound.Dy()
    if err != nil {
        log.Fatal(err)
    }
    // 缩略图的大小
    dst := image.NewRGBA(image.Rect(0, 0, newdx, newdx*dy/dx))
    // 产生缩略图,等比例缩放
    err = graphics.Scale(dst, src)
    if err != nil {
        log.Fatal(err)
    }
    header := w.Header()
    header.Add("Content-Type", "image/jpeg")
    png.Encode(w, dst)
}
// Load Image decodes an image from a file of image.
func LoadImage(path string) (img image.Image, err error) {
    file, err := os.Open(path)
    if err != nil {
        return
    }
    defer file.Close()
    img, _, err = image.Decode(file)
    return
}