url cache supported.

coolq/cqcode.go

 package coolq
 
 import (
+	"crypto/md5"
 	"encoding/base64"
 	"encoding/hex"
 	"errors"
@@ -261,10 +262,23 @@ func (bot *CQBot) ToElement(t string, d map[string]string, group bool) (message.
 	case "image":
 		f := d["file"]
 		if strings.HasPrefix(f, "http") || strings.HasPrefix(f, "https") {
+			cache := d["cache"]
+			if cache == "" {
+				cache = "1"
+			}
+			hash := md5.Sum([]byte(f))
+			cacheFile := path.Join(global.CACHE_PATH, hex.EncodeToString(hash[:])+".cache")
+			if global.PathExists(cacheFile) && cache == "1" {
+				b, err := ioutil.ReadFile(cacheFile)
+				if err == nil {
+					return message.NewImage(b), nil
+				}
+			}
 			b, err := global.GetBytes(f)
 			if err != nil {
 				return nil, err
 			}
+			_ = ioutil.WriteFile(cacheFile, b, 0644)
 			return message.NewImage(b), nil
 		}
 		if strings.HasPrefix(f, "base64") {

go.mod

@@ -3,7 +3,7 @@ module github.com/Mrs4s/go-cqhttp
 go 1.14
 
 require (
-	github.com/Mrs4s/MiraiGo v0.0.0-20200819041545-3561e5f156ce
+	github.com/Mrs4s/MiraiGo v0.0.0-20200819185537-8d1e5fb04c17
 	github.com/gin-gonic/gin v1.6.3
 	github.com/gorilla/websocket v1.4.2
 	github.com/guonaihong/gout v0.1.1

go.sum

 cloud.google.com/go v0.26.0/go.mod h1:aQUYkXzVsufM+DwF1aE+0xfcU+56JwCaLick0ClmMTw=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
-github.com/Mrs4s/MiraiGo v0.0.0-20200817175311-ac7fc7ad2847 h1:ZnCHrRSLvN+a7ndOFPJF/FIg80JM6WxiOGC1TPTarEk=
-github.com/Mrs4s/MiraiGo v0.0.0-20200817175311-ac7fc7ad2847/go.mod h1:0je03wji/tSw4bUH4QCF2Z4/EjyNWjSJTyy5tliX6EM=
-github.com/Mrs4s/MiraiGo v0.0.0-20200819041545-3561e5f156ce h1:rqefWaA8Xrk6qxFBbEQaySOUXH614DIR7cFmU5jVAQY=
-github.com/Mrs4s/MiraiGo v0.0.0-20200819041545-3561e5f156ce/go.mod h1:0je03wji/tSw4bUH4QCF2Z4/EjyNWjSJTyy5tliX6EM=
+github.com/Mrs4s/MiraiGo v0.0.0-20200819185537-8d1e5fb04c17 h1:sY4lwW34serGKnD26hP7ZLpnJ4NfVYKdS2SJIW1Mezs=
+github.com/Mrs4s/MiraiGo v0.0.0-20200819185537-8d1e5fb04c17/go.mod h1:0je03wji/tSw4bUH4QCF2Z4/EjyNWjSJTyy5tliX6EM=
 github.com/bwmarrin/snowflake v0.3.0 h1:xm67bEhkKh6ij1790JB83OujPR5CzNe8QuQqAgISZN0=
 github.com/bwmarrin/snowflake v0.3.0/go.mod h1:NdZxfVWX+oR6y2K0o6qAYv6gIOP9rjG0/E9WsDpxqwE=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=

main.go

@@ -51,6 +51,11 @@ func init() {
 			log.Fatalf("创建视频缓存文件夹失败: %v", err)
 		}
 	}
+	if !global.PathExists(global.CACHE_PATH) {
+		if err := os.MkdirAll(global.CACHE_PATH, 0755); err != nil {
+			log.Fatalf("创建发送图片缓存文件夹失败: %v", err)
+		}
+	}
 	if global.PathExists("cqhttp.json") {
 		log.Info("发现 cqhttp.json 将在五秒后尝试导入配置，按 Ctrl+C 取消.")
 		log.Warn("警告: 该操作会删除 cqhttp.json 并覆盖 config.json 文件.")