feat(instanceMgr): add getInfo endpoint to retrieve instance details

Implement new GET endpoint `/frpcAct/instanceMgr/getInfo` to fetch frpc instance information
Add documentation for the new API endpoint in docs/api.md
The handler returns different information based on user permission level

docs/api.md

@@ -1165,6 +1165,91 @@ X-Timestamp: 1704067200000
 
 ---
 
+## Get frpc Instance Information
+
+**Endpoint:** `/frpcAct/instanceMgr/getInfo`  
+**Method:** GET  
+**Auth Required:** Yes (token)  
+**Permission Level:** Visitor
+
+Retrieve information about a specific frpc instance. Returns different information based on user permission level.
+
+**Request Headers:**
+```
+X-Token: your_token
+X-Timestamp: 1704067200000
+```
+
+**Query Parameters:**
+```
+instanceID=1
+```
+
+| Header | Type | Required | Description |
+|--------|------|----------|-------------|
+| X-Token | string | Yes | Authentication token |
+| X-Timestamp | int64 | Yes | Client timestamp in milliseconds |
+
+| Parameter | Type | Required | Description |
+|-----------|------|----------|-------------|
+| instanceID | string | Yes | ID of the instance to get information for |
+
+**Response (Admin/Superuser):**
+```json
+{
+  "success": true,
+  "message": "Instance info retrieved successfully",
+  "data": {
+    "name": "my_frpc",
+    "serviceName": "superfrpc_admin_my_frpc",
+    "createdAt": "2024-01-01T00:00:00Z",
+    "createdBy": "admin",
+    "isRunning": true,
+    "serverAddr": "127.0.0.1",
+    "serverPort": "7000",
+    "auth_method": "token",
+    "bootAtStart": true,
+    "runUser": "root",
+    "configPath": "./configs/superfrpc_admin_my_frpc.toml"
+  }
+}
+```
+
+**Response (Visitor):**
+```json
+{
+  "success": true,
+  "message": "Instance info retrieved successfully",
+  "data": {
+    "name": "my_frpc",
+    "serviceName": "superfrpc_admin_my_frpc",
+    "createdAt": "2024-01-01T00:00:00Z",
+    "createdBy": "admin",
+    "isRunning": true,
+    "auth_method": "token",
+    "bootAtStart": true,
+    "runUser": "root",
+    "configPath": "./configs/superfrpc_admin_my_frpc.toml"
+  }
+}
+```
+
+| Field | Type | Description |
+|-------|------|-------------|
+| name | string | Name of the frpc instance |
+| serviceName | string | Service name |
+| createdAt | string | Instance creation time (ISO 8601 format) |
+| createdBy | string | Username of the user who created this instance |
+| isRunning | bool | Instance running status: true (running) or false (stopped) |
+| serverAddr | string | frps server address (only returned for admin/superuser) |
+| serverPort | string | frps server port (only returned for admin/superuser) |
+| auth_method | string | Authentication method |
+| bootAtStart | bool | Whether the instance starts automatically on system boot |
+| runUser | string | User that the instance runs as |
+| configPath | string | Path to the instance's configuration file |
+
+---
+
 ## Real-time Log Streaming (WebSocket)
 
 **Endpoint:** `/system/getLogs`  

frpAct.go

@@ -972,3 +972,99 @@ func GetInstanceStatusHandler(w http.ResponseWriter, r *http.Request) {
 	SendSuccessResponse(w, "Instance status retrieved successfully", responseData)
 	postLog.Info(fmt.Sprintf("[GetInstanceStatusHandler] Retrieved status for instance %d (name: %s), isRunning: %v", instanceID, instance.Name, isRunning))
 }
+
+func GetInstanceInfoHandler(w http.ResponseWriter, r *http.Request) {
+	if r.Method != http.MethodGet {
+		SendErrorResponse(w, http.StatusMethodNotAllowed, "Invalid request method")
+		postLog.Debug(fmt.Sprintf("[GetInstanceInfoHandler] Invalid request method: %s", r.Method))
+		return
+	}
+
+	queryParams := r.URL.Query()
+	instanceIDStr := queryParams.Get("instanceID")
+	if instanceIDStr == "" {
+		SendErrorResponse(w, http.StatusBadRequest, "instanceID is required")
+		return
+	}
+
+	instanceID, err := strconv.Atoi(instanceIDStr)
+	if err != nil {
+		SendErrorResponse(w, http.StatusBadRequest, "Invalid instanceID format")
+		return
+	}
+
+	userID, _, err := ValidateRequestWithHeader(w, r)
+	if err != nil {
+		postLog.Error(fmt.Sprintf("[GetInstanceInfoHandler] Failed to validate request header: %v", err))
+		SendErrorResponse(w, http.StatusBadRequest, "Invalid request header")
+		return
+	}
+
+	instance, err := DBQueryFrpcInstanceByID(instanceID)
+	if err == sql.ErrNoRows {
+		SendErrorResponse(w, http.StatusNotFound, "Instance not found")
+		postLog.Error(fmt.Sprintf("[GetInstanceInfoHandler] User %d tried to get info of a not existed instance: %d", userID, instanceID))
+		return
+	}
+	if err != nil {
+		postLog.Error(fmt.Sprintf("[GetInstanceInfoHandler] Failed to query instance: %v", err))
+		SendErrorResponse(w, http.StatusInternalServerError, "Failed to query instance")
+		return
+	}
+
+	if instance.UserID != userID {
+		SendErrorResponse(w, http.StatusForbidden, "Instance not found")
+		postLog.Error(fmt.Sprintf("[GetInstanceInfoHandler] User %d tried to get info of instance %d that does not belong to them", userID, instanceID))
+		return
+	}
+
+	userType, err := GetUserType(userID)
+	if err != nil {
+		postLog.Error(fmt.Sprintf("[GetInstanceInfoHandler] Failed to get user type: %v", err))
+		SendErrorResponse(w, http.StatusInternalServerError, "Failed to get user type")
+		return
+	}
+
+	serviceName, err := GetServiceNameByInstanceID(instanceID)
+	if err != nil {
+		postLog.Error(fmt.Sprintf("[GetInstanceInfoHandler] Failed to get service name: %v", err))
+		SendErrorResponse(w, http.StatusInternalServerError, "Failed to get service name")
+		return
+	}
+
+	isRunning := IsInstanceRunning(instanceID)
+
+	responseData := map[string]interface{}{
+		"name":        instance.Name,
+		"serviceName": serviceName,
+		"createdAt":   instance.CreatedAt,
+		"createdBy":   instance.CreatedBy,
+		"isRunning":   isRunning,
+		"auth_method": "",
+		"bootAtStart": instance.BootAtStart,
+		"runUser":     instance.RunUser,
+		"configPath":  instance.ConfigPath,
+	}
+
+	configContent, err := os.ReadFile(instance.ConfigPath)
+	if err == nil {
+		config, err := decodeFrpcConfig(string(configContent))
+		if err == nil {
+			if authMethod, ok := config.Global["auth.method"]; ok {
+				responseData["auth_method"] = authMethod
+			}
+
+			if userType == "admin" || userType == "superuser" {
+				if serverAddr, ok := config.Global["serverAddr"]; ok {
+					responseData["serverAddr"] = serverAddr
+				}
+				if serverPort, ok := config.Global["serverPort"]; ok {
+					responseData["serverPort"] = serverPort
+				}
+			}
+		}
+	}
+
+	SendSuccessResponse(w, "Instance info retrieved successfully", responseData)
+	postLog.Info(fmt.Sprintf("[GetInstanceInfoHandler] Retrieved info for instance %d (name: %s), userType: %s", instanceID, instance.Name, userType))
+}

router.go

@@ -33,6 +33,7 @@ func setupRoutes() {
 	http.HandleFunc("/frpcAct/instanceMgr/stop", StopInstanceHandler)
 	http.HandleFunc("/frpcAct/instanceMgr/restart", RestartInstanceHandler)
 	http.HandleFunc("/frpcAct/instanceMgr/status", GetInstanceStatusHandler)
+	http.HandleFunc("/frpcAct/instanceMgr/getInfo", GetInstanceInfoHandler)
 	http.HandleFunc("/frpcAct/proxyMgr/create", CreateProxyHandler)
 	http.HandleFunc("/frpcAct/proxyMgr/delete", DeleteProxyHandler)
 	http.HandleFunc("/frpcAct/proxyMgr/list", ListProxiesHandler)