added the configurable items sse_read_timeout and headers to mcp-client (#55)

* add configurable items sse_read_timeout and headers.

* update

* set sseReadTimeout default value

* init headers in NewSSEMCPClient function

* delete ToolInputSchema Properties  json omitempty tag

According to the mcp's structural definition of the tool, inputSchema.properties cannot be null

* fix withTimeout param

Author: resurgence72

client/sse.go

@@ -23,35 +23,59 @@ import (
 // while sending requests over regular HTTP POST calls. The client handles
 // automatic reconnection and message routing between requests and responses.
 type SSEMCPClient struct {
-	baseURL       *url.URL
-	endpoint      *url.URL
-	httpClient    *http.Client
-	requestID     atomic.Int64
-	responses     map[int64]chan RPCResponse
-	mu            sync.RWMutex
-	done          chan struct{}
-	initialized   bool
-	notifications []func(mcp.JSONRPCNotification)
-	notifyMu      sync.RWMutex
-	endpointChan  chan struct{}
-	capabilities  mcp.ServerCapabilities
+	baseURL        *url.URL
+	endpoint       *url.URL
+	httpClient     *http.Client
+	requestID      atomic.Int64
+	responses      map[int64]chan RPCResponse
+	mu             sync.RWMutex
+	done           chan struct{}
+	initialized    bool
+	notifications  []func(mcp.JSONRPCNotification)
+	notifyMu       sync.RWMutex
+	endpointChan   chan struct{}
+	capabilities   mcp.ServerCapabilities
+	headers        map[string]string
+	sseReadTimeout time.Duration
+}
+
+type ClientOption func(*SSEMCPClient)
+
+func WithHeaders(headers map[string]string) ClientOption {
+	return func(sc *SSEMCPClient) {
+		sc.headers = headers
+	}
+}
+
+func WithSSEReadTimeout(timeout time.Duration) ClientOption {
+	return func(sc *SSEMCPClient) {
+		sc.sseReadTimeout = timeout
+	}
 }
 
 // NewSSEMCPClient creates a new SSE-based MCP client with the given base URL.
 // Returns an error if the URL is invalid.
-func NewSSEMCPClient(baseURL string) (*SSEMCPClient, error) {
+func NewSSEMCPClient(baseURL string, options ...ClientOption) (*SSEMCPClient, error) {
 	parsedURL, err := url.Parse(baseURL)
 	if err != nil {
 		return nil, fmt.Errorf("invalid URL: %w", err)
 	}
 
-	return &SSEMCPClient{
-		baseURL:      parsedURL,
-		httpClient:   &http.Client{},
-		responses:    make(map[int64]chan RPCResponse),
-		done:         make(chan struct{}),
-		endpointChan: make(chan struct{}),
-	}, nil
+	smc := &SSEMCPClient{
+		baseURL:        parsedURL,
+		httpClient:     &http.Client{},
+		responses:      make(map[int64]chan RPCResponse),
+		done:           make(chan struct{}),
+		endpointChan:   make(chan struct{}),
+		sseReadTimeout: 30 * time.Second,
+		headers:        make(map[string]string),
+	}
+
+	for _, opt := range options {
+		opt(smc)
+	}
+
+	return smc, nil
 }
 
 // Start initiates the SSE connection to the server and waits for the endpoint information.
@@ -104,41 +128,49 @@ func (c *SSEMCPClient) readSSE(reader io.ReadCloser) {
 	br := bufio.NewReader(reader)
 	var event, data string
 
+	ctx, cancel := context.WithTimeout(context.Background(), c.sseReadTimeout)
+	defer cancel()
+
 	for {
-		line, err := br.ReadString('\n')
-		if err != nil {
-			if err == io.EOF {
-				// Process any pending event before exit
+		select {
+		case <-ctx.Done():
+			return
+		default:
+			line, err := br.ReadString('\n')
+			if err != nil {
+				if err == io.EOF {
+					// Process any pending event before exit
+					if event != "" && data != "" {
+						c.handleSSEEvent(event, data)
+					}
+					break
+				}
+				select {
+				case <-c.done:
+					return
+				default:
+					fmt.Printf("SSE stream error: %v\n", err)
+					return
+				}
+			}
+
+			// Remove only newline markers
+			line = strings.TrimRight(line, "\r\n")
+			if line == "" {
+				// Empty line means end of event
 				if event != "" && data != "" {
 					c.handleSSEEvent(event, data)
+					event = ""
+					data = ""
 				}
-				break
-			}
-			select {
-			case <-c.done:
-				return
-			default:
-				fmt.Printf("SSE stream error: %v\n", err)
-				return
+				continue
 			}
-		}
 
-		// Remove only newline markers
-		line = strings.TrimRight(line, "\r\n")
-		if line == "" {
-			// Empty line means end of event
-			if event != "" && data != "" {
-				c.handleSSEEvent(event, data)
-				event = ""
-				data = ""
+			if strings.HasPrefix(line, "event:") {
+				event = strings.TrimSpace(strings.TrimPrefix(line, "event:"))
+			} else if strings.HasPrefix(line, "data:") {
+				data = strings.TrimSpace(strings.TrimPrefix(line, "data:"))
 			}
-			continue
-		}
-
-		if strings.HasPrefix(line, "event:") {
-			event = strings.TrimSpace(strings.TrimPrefix(line, "event:"))
-		} else if strings.HasPrefix(line, "data:") {
-			data = strings.TrimSpace(strings.TrimPrefix(line, "data:"))
 		}
 	}
 }
@@ -269,6 +301,10 @@ func (c *SSEMCPClient) sendRequest(
 	}
 
 	req.Header.Set("Content-Type", "application/json")
+	// set custom http headers
+	for k, v := range c.headers {
+		req.Header.Set(k, v)
+	}
 
 	resp, err := c.httpClient.Do(req)
 	if err != nil {

mcp/tools.go

@@ -105,7 +105,7 @@ func (t Tool) MarshalJSON() ([]byte, error) {
 
 type ToolInputSchema struct {
 	Type       string                 `json:"type"`
-	Properties map[string]interface{} `json:"properties,omitempty"`
+	Properties map[string]interface{} `json:"properties"`
 	Required   []string               `json:"required,omitempty"`
 }