无损压缩GIF

bin/main.go

@@ -18,17 +18,61 @@ import (
 )
 
 func init() {
-	// 设置日志格式
 	log.SetFlags(log.Ldate | log.Ltime | log.Lshortfile)
 }
 
-// 实现一个 web api 服务(获取指定尺寸的图片)
+// string 转换为 int, 如果转换失败则返回默认值
+func stringToInt(str string, defaultValue int) int {
+	if str == "" {
+		return defaultValue
+	}
+	value, err := strconv.Atoi(str)
+	if err != nil {
+		return defaultValue
+	}
+	return value
+}
+
 func main() {
 	runtime.GOMAXPROCS(runtime.NumCPU())
-	models.GetMysql() // 测试连接数据库
+
+	var mysqlConnection models.MysqlConnection
+	mysqlConnection.Init()
+
+	// 直接走 CDN 的请求不缓存本地, 因此直接使用参数
+	http.HandleFunc("/webp/", func(w http.ResponseWriter, r *http.Request) {
+		log.Println(r.Method, r.URL.Path)
+		// URL 格式: /img/{id}.{格式}?width=320&height=320&fit=cover
+		reg := regexp.MustCompile(`^/webp/([0-9a-zA-Z]+).(jpg|jpeg|png|webp)$`)
+		matches := reg.FindStringSubmatch(r.URL.Path)
+		if len(matches) != 3 {
+			log.Println("URL 格式错误", matches)
+			w.WriteHeader(http.StatusNotFound)
+			return
+		}
+
+		id, format, width, height, fit := matches[1], matches[2], stringToInt(r.URL.Query().Get("width"), 0), stringToInt(r.URL.Query().Get("height"), 0), r.URL.Query().Get("fit")
+		content, err := mysqlConnection.GetImageContent(id)
+		if err != nil {
+			log.Println("获取图片失败", format, err)
+			w.WriteHeader(http.StatusBadRequest)
+		}
+
+		var img models.Image
+		img.Init(content)
+
+		data, err := img.ToWebP(width, height, fit)
+		if err != nil {
+			log.Println("转换图片失败", err)
+			w.WriteHeader(http.StatusBadRequest)
+		}
+
+		w.Header().Set("Content-Type", "image/webp")
+		w.Header().Set("Cache-Control", "max-age=31536000")
+		w.Write(data)
+	})
 
 	http.HandleFunc("/img/", func(w http.ResponseWriter, r *http.Request) {
-
 		// URL 格式: /img/{id}-{version}@{倍图}{宽度}.{格式}
 		reg := regexp.MustCompile(`^/img/([0-9a-zA-Z]+)-([0-9a-zA-Z]+)@([0-9]{1,4})x([0-9]{1,4}).(jpg|jpeg|png|webp)$`)
 		matches := reg.FindStringSubmatch(r.URL.Path)