feat: support balance query for CloseAI (#240)

* 增加CloseAI余额查询功能

* 去除debug代码

* fix: bug fix

* docs: update README

---------

Co-authored-by: sudongyang <sudongyang@xiaomi.com>
Co-authored-by: JustSong <songquanpeng@foxmail.com>

controller/channel-billing.go

@@ -32,6 +32,13 @@ type OpenAIUsageDailyCost struct {
 	}
 }
 
+type OpenAICreditGrants struct {
+	Object         string  `json:"object"`
+	TotalGranted   float64 `json:"total_granted"`
+	TotalUsed      float64 `json:"total_used"`
+	TotalAvailable float64 `json:"total_available"`
+}
+
 type OpenAIUsageResponse struct {
 	Object string `json:"object"`
 	//DailyCosts []OpenAIUsageDailyCost `json:"daily_costs"`
@@ -100,6 +107,22 @@ func GetResponseBody(method, url string, channel *model.Channel, headers http.He
 	return body, nil
 }
 
+func updateChannelCloseAIBalance(channel *model.Channel) (float64, error) {
+	url := fmt.Sprintf("%s/dashboard/billing/credit_grants", channel.BaseURL)
+	body, err := GetResponseBody("GET", url, channel, GetAuthHeader(channel.Key))
+
+	if err != nil {
+		return 0, err
+	}
+	response := OpenAICreditGrants{}
+	err = json.Unmarshal(body, &response)
+	if err != nil {
+		return 0, err
+	}
+	channel.UpdateBalance(response.TotalAvailable)
+	return response.TotalAvailable, nil
+}
+
 func updateChannelOpenAISBBalance(channel *model.Channel) (float64, error) {
 	url := fmt.Sprintf("https://api.openai-sb.com/sb-api/user/status?api_key=%s", channel.Key)
 	body, err := GetResponseBody("GET", url, channel, GetAuthHeader(channel.Key))
@@ -175,6 +198,9 @@ func updateChannelAIGC2DBalance(channel *model.Channel) (float64, error) {
 
 func updateChannelBalance(channel *model.Channel) (float64, error) {
 	baseURL := common.ChannelBaseURLs[channel.Type]
+	if channel.BaseURL == "" {
+		channel.BaseURL = baseURL
+	}
 	switch channel.Type {
 	case common.ChannelTypeOpenAI:
 		if channel.BaseURL != "" {
@@ -184,6 +210,8 @@ func updateChannelBalance(channel *model.Channel) (float64, error) {
 		return 0, errors.New("尚未实现")
 	case common.ChannelTypeCustom:
 		baseURL = channel.BaseURL
+	case common.ChannelTypeCloseAI:
+		return updateChannelCloseAIBalance(channel)
 	case common.ChannelTypeOpenAISB:
 		return updateChannelOpenAISBBalance(channel)
 	case common.ChannelTypeAIProxy: