feat: support google v1beta and Gemini Ultra

relay/channel/gemini/adaptor.go

@@ -18,16 +18,28 @@ type Adaptor struct {
 func (a *Adaptor) Init(info *relaycommon.RelayInfo, request dto.GeneralOpenAIRequest) {
 }
 
+// 定义一个映射，存储模型名称和对应的版本
+var modelVersionMap = map[string]string{
+    "gemini-1.5-pro": "v1beta",
+    "gemini-ultra":   "v1beta",
+}
+
 func (a *Adaptor) GetRequestURL(info *relaycommon.RelayInfo) (string, error) {
-	version := "v1"
-	if info.ApiVersion != "" {
-		version = info.ApiVersion
-	}
-	action := "generateContent"
-	if info.IsStream {
-		action = "streamGenerateContent"
-	}
-	return fmt.Sprintf("%s/%s/models/%s:%s", info.BaseUrl, version, info.UpstreamModelName, action), nil
+    // 从映射中获取模型名称对应的版本，如果找不到就使用 info.ApiVersion 或默认的版本 "v1"
+    version, beta := modelVersionMap[info.UpstreamModelName]
+    if !beta {
+        if info.ApiVersion != "" {
+            version = info.ApiVersion
+        } else {
+            version = "v1"
+        }
+    }
+
+    action := "generateContent"
+    if info.IsStream {
+        action = "streamGenerateContent"
+    }
+    return fmt.Sprintf("%s/%s/models/%s:%s", info.BaseUrl, version, info.UpstreamModelName, action), nil
 }
 
 func (a *Adaptor) SetupRequestHeader(c *gin.Context, req *http.Request, info *relaycommon.RelayInfo) error {