Fix the problem that mcp request id is not of int type (#4914)

mcp/server.go

@@ -173,17 +173,20 @@ func (s *sseMcpServer) handleRequest(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
-	w.WriteHeader(http.StatusAccepted)
-
 	// For notification methods (no ID), we don't send a response
-	isNotification := req.ID == 0
+	isNotification, err := req.isNotification()
+	if err != nil {
+		http.Error(w, "Invalid request.ID", http.StatusBadRequest)
+	}
+
+	w.WriteHeader(http.StatusAccepted)
 
 	// Special handling for initialization sequence
 	// Always allow initialize and notifications/initialized regardless of client state
 	if req.Method == methodInitialize {
-		logx.Infof("Processing initialize request with ID: %d", req.ID)
+		logx.Infof("Processing initialize request with ID: %v", req.ID)
 		s.processInitialize(r.Context(), client, req)
-		logx.Infof("Sent initialize response for ID: %d, waiting for notifications/initialized", req.ID)
+		logx.Infof("Sent initialize response for ID: %v, waiting for notifications/initialized", req.ID)
 		return
 	} else if req.Method == methodNotificationsInitialized {
 		// Handle initialized notification
@@ -206,41 +209,41 @@ func (s *sseMcpServer) handleRequest(w http.ResponseWriter, r *http.Request) {
 	// Process normal requests only after initialization
 	switch req.Method {
 	case methodToolsCall:
-		logx.Infof("Received tools call request with ID: %d", req.ID)
+		logx.Infof("Received tools call request with ID: %v", req.ID)
 		s.processToolCall(r.Context(), client, req)
-		logx.Infof("Sent tools call response for ID: %d", req.ID)
+		logx.Infof("Sent tools call response for ID: %v", req.ID)
 	case methodToolsList:
-		logx.Infof("Processing tools/list request with ID: %d", req.ID)
+		logx.Infof("Processing tools/list request with ID: %v", req.ID)
 		s.processListTools(r.Context(), client, req)
-		logx.Infof("Sent tools/list response for ID: %d", req.ID)
+		logx.Infof("Sent tools/list response for ID: %v", req.ID)
 	case methodPromptsList:
-		logx.Infof("Processing prompts/list request with ID: %d", req.ID)
+		logx.Infof("Processing prompts/list request with ID: %v", req.ID)
 		s.processListPrompts(r.Context(), client, req)
-		logx.Infof("Sent prompts/list response for ID: %d", req.ID)
+		logx.Infof("Sent prompts/list response for ID: %v", req.ID)
 	case methodPromptsGet:
-		logx.Infof("Processing prompts/get request with ID: %d", req.ID)
+		logx.Infof("Processing prompts/get request with ID: %v", req.ID)
 		s.processGetPrompt(r.Context(), client, req)
-		logx.Infof("Sent prompts/get response for ID: %d", req.ID)
+		logx.Infof("Sent prompts/get response for ID: %v", req.ID)
 	case methodResourcesList:
-		logx.Infof("Processing resources/list request with ID: %d", req.ID)
+		logx.Infof("Processing resources/list request with ID: %v", req.ID)
 		s.processListResources(r.Context(), client, req)
-		logx.Infof("Sent resources/list response for ID: %d", req.ID)
+		logx.Infof("Sent resources/list response for ID: %v", req.ID)
 	case methodResourcesRead:
-		logx.Infof("Processing resources/read request with ID: %d", req.ID)
+		logx.Infof("Processing resources/read request with ID: %v", req.ID)
 		s.processResourcesRead(r.Context(), client, req)
-		logx.Infof("Sent resources/read response for ID: %d", req.ID)
+		logx.Infof("Sent resources/read response for ID: %v", req.ID)
 	case methodResourcesSubscribe:
-		logx.Infof("Processing resources/subscribe request with ID: %d", req.ID)
+		logx.Infof("Processing resources/subscribe request with ID: %v", req.ID)
 		s.processResourceSubscribe(r.Context(), client, req)
-		logx.Infof("Sent resources/subscribe response for ID: %d", req.ID)
+		logx.Infof("Sent resources/subscribe response for ID: %v", req.ID)
 	case methodPing:
-		logx.Infof("Processing ping request with ID: %d", req.ID)
+		logx.Infof("Processing ping request with ID: %v", req.ID)
 		s.processPing(r.Context(), client, req)
 	case methodNotificationsCancelled:
-		logx.Infof("Received notifications/cancelled notification: %d", req.ID)
+		logx.Infof("Received notifications/cancelled notification: %v", req.ID)
 		s.processNotificationCancelled(r.Context(), client, req)
 	default:
-		logx.Infof("Unknown method: %s from client: %d", req.Method, req.ID)
+		logx.Infof("Unknown method: %s from client: %v", req.Method, req.ID)
 		s.sendErrorResponse(r.Context(), client, req.ID, "Method not found", errCodeMethodNotFound)
 	}
 }
@@ -880,10 +883,10 @@ func (s *sseMcpServer) processPing(ctx context.Context, client *mcpClient, req R
 
 // sendErrorResponse sends an error response via the SSE channel
 func (s *sseMcpServer) sendErrorResponse(ctx context.Context, client *mcpClient,
-	id int64, message string, code int) {
+	id any, message string, code int) {
 	errorResponse := struct {
 		JsonRpc string       `json:"jsonrpc"`
-		ID      int64        `json:"id"`
+		ID      any          `json:"id"`
 		Error   errorMessage `json:"error"`
 	}{
 		JsonRpc: jsonRpcVersion,
@@ -898,7 +901,7 @@ func (s *sseMcpServer) sendErrorResponse(ctx context.Context, client *mcpClient,
 	jsonData, _ := json.Marshal(errorResponse)
 	// Use CRLF line endings as requested
 	sseMessage := fmt.Sprintf("event: %s\r\ndata: %s\r\n\r\n", eventMessage, string(jsonData))
-	logx.Infof("Sending error for ID %d: %s", id, sseMessage)
+	logx.Infof("Sending error for ID %v: %s", id, sseMessage)
 
 	// cannot receive from ctx.Done() because we're sending to the channel for SSE messages
 	select {
@@ -910,7 +913,7 @@ func (s *sseMcpServer) sendErrorResponse(ctx context.Context, client *mcpClient,
 }
 
 // sendResponse sends a success response via the SSE channel
-func (s *sseMcpServer) sendResponse(ctx context.Context, client *mcpClient, id int64, result any) {
+func (s *sseMcpServer) sendResponse(ctx context.Context, client *mcpClient, id any, result any) {
 	response := Response{
 		JsonRpc: jsonRpcVersion,
 		ID:      id,
@@ -925,13 +928,13 @@ func (s *sseMcpServer) sendResponse(ctx context.Context, client *mcpClient, id i
 
 	// Use CRLF line endings as requested
 	sseMessage := fmt.Sprintf("event: %s\r\ndata: %s\r\n\r\n", eventMessage, string(jsonData))
-	logx.Infof("Sending response for ID %d: %s", id, sseMessage)
+	logx.Infof("Sending response for ID %v: %s", id, sseMessage)
 
 	// cannot receive from ctx.Done() because we're sending to the channel for SSE messages
 	select {
 	case client.channel <- sseMessage:
 	default:
 		// Channel buffer is full, log warning and continue
-		logx.Infof("Client %s channel is full while sending response with ID %d", client.id, id)
+		logx.Infof("Client %s channel is full while sending response with ID %v", client.id, id)
 	}
 }

mcp/types.go

@@ -3,6 +3,7 @@ package mcp
 import (
 	"context"
 	"encoding/json"
+	"fmt"
 	"sync"
 
 	"github.com/zeromicro/go-zero/rest"
@@ -15,11 +16,31 @@ type Cursor string
 type Request struct {
 	SessionId string          `form:"session_id"` // Session identifier for client tracking
 	JsonRpc   string          `json:"jsonrpc"`    // Must be "2.0" per JSON-RPC spec
-	ID        int64           `json:"id"`         // Request identifier for matching responses
+	ID        any             `json:"id"`         // Request identifier for matching responses
 	Method    string          `json:"method"`     // Method name to invoke
 	Params    json.RawMessage `json:"params"`     // Parameters for the method
 }
 
+func (r Request) isNotification() (bool, error) {
+	var isNotification bool
+	switch val := r.ID.(type) {
+	case int:
+		isNotification = val == 0
+	case int64:
+		isNotification = val == 0
+	case float64:
+		isNotification = val == 0.0
+	case string:
+		isNotification = len(val) == 0
+	case nil:
+		isNotification = true
+	default:
+		return false, fmt.Errorf("invalid type %T", val)
+	}
+
+	return isNotification, nil
+}
+
 type PaginatedParams struct {
 	Cursor string `json:"cursor"`
 	Meta   struct {
@@ -244,7 +265,7 @@ type errorObj struct {
 // Response represents a JSON-RPC response
 type Response struct {
 	JsonRpc string    `json:"jsonrpc"`         // Always "2.0"
-	ID      int64     `json:"id"`              // Same as request ID
+	ID      any       `json:"id"`              // Same as request ID
 	Result  any       `json:"result"`          // Result object (null if error)
 	Error   *errorObj `json:"error,omitempty"` // Error object (null if success)
 }

mcp/types_test.go

@@ -3,6 +3,7 @@ package mcp
 import (
 	"context"
 	"encoding/json"
+	"errors"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -55,7 +56,7 @@ func TestRequestUnmarshaling(t *testing.T) {
 
 	assert.NoError(t, err)
 	assert.Equal(t, "2.0", req.JsonRpc)
-	assert.Equal(t, int64(789), req.ID)
+	assert.Equal(t, float64(789), req.ID)
 	assert.Equal(t, "test_method", req.Method)
 
 	// Check params unmarshaled correctly
@@ -204,3 +205,67 @@ func TestCallToolResult(t *testing.T) {
 	assert.Contains(t, string(data), `"content":[{"text":"Sample result"}]`)
 	assert.NotContains(t, string(data), `"isError":`)
 }
+
+func TestRequest_isNotification(t *testing.T) {
+	tests := []struct {
+		name    string
+		id      any
+		want    bool
+		wantErr error
+	}{
+		// integer test cases
+		{name: "int zero", id: 0, want: true, wantErr: nil},
+		{name: "int non-zero", id: 1, want: false, wantErr: nil},
+		{name: "int64 zero", id: int64(0), want: true, wantErr: nil},
+		{name: "int64 max", id: int64(9223372036854775807), want: false, wantErr: nil},
+
+		// floating point number test cases
+		{name: "float64 zero", id: float64(0.0), want: true, wantErr: nil},
+		{name: "float64 positive", id: float64(0.000001), want: false, wantErr: nil},
+		{name: "float64 negative", id: float64(-0.000001), want: false, wantErr: nil},
+		{name: "float64 epsilon", id: float64(1e-300), want: false, wantErr: nil},
+
+		// string test cases
+		{name: "empty string", id: "", want: true, wantErr: nil},
+		{name: "non-empty string", id: "abc", want: false, wantErr: nil},
+		{name: "space string", id: " ", want: false, wantErr: nil},
+		{name: "unicode string", id: "こんにちは", want: false, wantErr: nil},
+
+		// special cases
+		{name: "nil", id: nil, want: true, wantErr: nil},
+
+		// logical type test cases
+		{name: "bool true", id: true, want: false, wantErr: errors.New("invalid type bool")},
+		{name: "bool false", id: false, want: false, wantErr: errors.New("invalid type bool")},
+		{name: "struct type", id: struct{}{}, want: false, wantErr: errors.New("invalid type struct {}")},
+		{name: "slice type", id: []int{1, 2, 3}, want: false, wantErr: errors.New("invalid type []int")},
+		{name: "map type", id: map[string]int{"a": 1}, want: false, wantErr: errors.New("invalid type map[string]int")},
+		{name: "pointer type", id: new(int), want: false, wantErr: errors.New("invalid type *int")},
+		{name: "func type", id: func() {}, want: false, wantErr: errors.New("invalid type func()")},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req := Request{
+				SessionId: "test-session",
+				JsonRpc:   "2.0",
+				ID:        tt.id,
+				Method:    "testMethod",
+				Params:    json.RawMessage(`{}`),
+			}
+
+			got, err := req.isNotification()
+
+			if (err != nil) != (tt.wantErr != nil) {
+				t.Fatalf("error presence mismatch: got error = %v, wantErr %v", err, tt.wantErr)
+			}
+			if err != nil && tt.wantErr != nil && err.Error() != tt.wantErr.Error() {
+				t.Fatalf("error message mismatch:\ngot  %q\nwant %q", err.Error(), tt.wantErr.Error())
+			}
+
+			if got != tt.want {
+				t.Errorf("isNotification() = %v, want %v for ID %v (%T)", got, tt.want, tt.id, tt.id)
+			}
+		})
+	}
+}