optimize http get/post

Author: omigo

custom.go

@@ -3,8 +3,6 @@ package weixin
 import (
 	"encoding/json"
 	"fmt"
-	"io/ioutil"
-	"net/http"
 	"os"
 )
 
@@ -64,26 +62,19 @@ func DeleteCustomStruct(cust *Custom) (err error) {
 
 // operateCustomStruct 客服帐号
 func operateCustomStruct(url string, cust *Custom) (err error) {
-	jsonBytes, err := json.Marshal(cust)
-	if err != nil {
-		return err
-	}
-
-	err = Post(url, jsonBytes)
-	return err
+	return Post(url, cust, nil)
 }
 
 // UploadHeading 设置客服帐号的头像
 func UploadHeading(account string, file *os.File) (err error) {
 	url := fmt.Sprintf(CustomHeadingURL, AccessToken(), account)
-	wxerr := &WeixinError{} // 忽略返回
-	return Upload(url, file.Name(), file, wxerr)
+	return Upload(url, file.Name(), file, nil)
 }
 
 // CustomList 客服列表
 type CustomList struct {
-	WeixinError
-	List []Account `json:"kf_list"`
+	WXError
+	List []*Account `json:"kf_list"`
 }
 
 // Account 客服账号
@@ -95,29 +86,11 @@ type Account struct {
 }
 
 // GetCustomList 获取所有客服账号
-func GetCustomList() (accs []Account, err error) {
+func GetCustomList() (accs []*Account, err error) {
 	url := fmt.Sprintf(CustomListURL, AccessToken())
-	resp, err := http.Get(url)
-	if err != nil {
-		return nil, err
-	}
-
-	body, err := ioutil.ReadAll(resp.Body)
-	if err != nil {
-		return nil, err
-	}
-
 	list := &CustomList{}
-	err = json.Unmarshal(body, list)
-	if err != nil {
-		return nil, err
-	}
-
-	if list.ErrCode != WeixinErrCodeSuccess {
-		return nil, list
-	}
-
-	return list.List, nil
+	err = Get(url, list)
+	return list.List, err
 }
 
 // CustMsg 客服消息接口
@@ -199,7 +172,5 @@ func SendCustomMsg(openId string, msg CustMsg) (err error) {
 		openId, msgType, msgType, js)
 
 	url := fmt.Sprintf(CustomMsgURL, AccessToken())
-	err = Post(url, []byte(jsonStr))
-
-	return err
+	return Post(url, []byte(jsonStr), nil)
 }

errors.go

@@ -0,0 +1,142 @@
+package weixin
+
+import (
+	"bytes"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"mime"
+	"mime/multipart"
+	"net/http"
+	"os"
+
+	"github.com/arstd/log"
+)
+
+type wxResp interface {
+	// 似有的 error 方法，保证外部(其他包)定义的 struct 只能内嵌
+	// WXError 的才能实现这个方法，才能作为当前包 http 方法的参数
+	error() error
+}
+
+type WXError struct {
+	ErrCode int    `json:"errcode,omitempty"`
+	Errmsg  string `json:"errmsg,omitempty"`
+}
+
+func (e *WXError) error() error {
+	if e.ErrCode == 0 {
+		return nil
+	}
+	return e
+}
+
+func (e *WXError) Error() string {
+	return fmt.Sprintf("weixin: (%d)%s", e.ErrCode, e.Errmsg)
+}
+
+var client = http.Client{
+	Transport: &http.Transport{
+		MaxIdleConnsPerHost: 128,
+	},
+}
+
+// GetUnmarshal HTTP 工具类, GET 并解析返回的报文，如果有错误，返回 error
+func Get(url string, wxr wxResp) error {
+	resp, err := client.Get(url)
+	if err != nil {
+		return err
+	}
+
+	return parseWXResp(resp, wxr)
+}
+
+const contentType = "application/json"
+
+// Post HTTP 工具类, POST 并解析返回的报文，如果有错误，返回 error
+func Post(url string, v interface{}, wxr wxResp) (err error) {
+	var js []byte
+	if _, ok := v.([]byte); !ok {
+		js, err = json.Marshal(v)
+		if err != nil {
+			return err
+		}
+	}
+
+	resp, err := client.Post(url, contentType, bytes.NewBuffer(js))
+	if err != nil {
+		return err
+	}
+	return parseWXResp(resp, wxr)
+}
+
+// Upload 工具类, 上传文件
+func Upload(url, fieldName string, file *os.File, wxr wxResp, desc ...string) (err error) {
+	buf := &bytes.Buffer{}
+	w := multipart.NewWriter(buf)
+
+	//关键的一步操作
+	// fw, err := w.CreateFormField(file.Name())
+	fw, err := w.CreateFormFile(fieldName, file.Name())
+	if err != nil {
+		return err
+	}
+	_, err = io.Copy(fw, file)
+	if err != nil {
+		return err
+	}
+	contentType := w.FormDataContentType()
+	if len(desc) > 0 {
+		w.WriteField("description", desc[0])
+	}
+	w.Close()
+
+	log.Debugf("url=%s, fieldName=%s, fileName=%s", url, fieldName, file.Name())
+	resp, err := client.Post(url, contentType, buf)
+	if err != nil {
+		return err
+	}
+
+	return parseWXResp(resp, wxr)
+}
+
+func Download(url string) (filename string, body []byte, err error) {
+	resp, err := client.Get(url)
+	if err != nil {
+		return "", nil, err
+	}
+
+	var params map[string]string
+	if cd := resp.Header.Get("Content-Disposition"); cd == "" {
+		return "", nil, errors.New("missing Content-Disposition header")
+	} else if _, params, err = mime.ParseMediaType(cd); err != nil {
+		return "", nil, err
+	} else if filename = params["filename"]; filename == "" {
+		return "", nil, errors.New("no filename in Content-Disposition header")
+	}
+
+	body, err = ioutil.ReadAll(resp.Body)
+	resp.Body.Close()
+	return filename, body, err
+}
+
+func parseWXResp(resp *http.Response, wxr wxResp) error {
+	js, err := ioutil.ReadAll(resp.Body)
+	resp.Body.Close()
+	if err != nil {
+		return err
+	}
+
+	log.Trace("%s", js)
+	if wxr == nil {
+		wxr = &WXError{}
+	}
+	err = json.Unmarshal(js, wxr)
+	if err != nil {
+		return err
+	}
+
+	return wxr.error()
+}