feat!: remove WebSocketClientTransport (#1783)

Co-authored-by: Konstantin Konstantinov <KKonstantinov@users.noreply.github.com>

packages/client/src/client/websocket.ts

@@ -1,74 +0,0 @@
-import type { JSONRPCMessage, Transport } from '@modelcontextprotocol/core';
-import { JSONRPCMessageSchema } from '@modelcontextprotocol/core';
-
-const SUBPROTOCOL = 'mcp';
-
-/**
- * Client transport for WebSocket: this will connect to a server over the WebSocket protocol.
- */
-export class WebSocketClientTransport implements Transport {
-    private _socket?: WebSocket;
-    private _url: URL;
-
-    onclose?: () => void;
-    onerror?: (error: Error) => void;
-    onmessage?: (message: JSONRPCMessage) => void;
-
-    constructor(url: URL) {
-        this._url = url;
-    }
-
-    start(): Promise<void> {
-        if (this._socket) {
-            throw new Error(
-                'WebSocketClientTransport already started! If using Client class, note that connect() calls start() automatically.'
-            );
-        }
-
-        return new Promise((resolve, reject) => {
-            this._socket = new WebSocket(this._url, SUBPROTOCOL);
-
-            this._socket.onerror = event => {
-                const error = 'error' in event ? (event.error as Error) : new Error(`WebSocket error: ${JSON.stringify(event)}`);
-                reject(error);
-                this.onerror?.(error);
-            };
-
-            this._socket.onopen = () => {
-                resolve();
-            };
-
-            this._socket.onclose = () => {
-                this.onclose?.();
-            };
-
-            this._socket.onmessage = (event: MessageEvent) => {
-                let message: JSONRPCMessage;
-                try {
-                    message = JSONRPCMessageSchema.parse(JSON.parse(event.data));
-                } catch (error) {
-                    this.onerror?.(error as Error);
-                    return;
-                }
-
-                this.onmessage?.(message);
-            };
-        });
-    }
-
-    async close(): Promise<void> {
-        this._socket?.close();
-    }
-
-    send(message: JSONRPCMessage): Promise<void> {
-        return new Promise((resolve, reject) => {
-            if (!this._socket) {
-                reject(new Error('Not connected'));
-                return;
-            }
-
-            this._socket?.send(JSON.stringify(message));
-            resolve();
-        });
-    }
-}

packages/client/src/index.ts

@@ -69,7 +69,6 @@ export type {
     StreamableHTTPReconnectionOptions
 } from './client/streamableHttp.js';
 export { StreamableHTTPClientTransport } from './client/streamableHttp.js';
-export { WebSocketClientTransport } from './client/websocket.js';
 
 // experimental exports
 export { ExperimentalClientTasks } from './experimental/tasks/client.js';