websocket.js 1.8 KB

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  1. import { JSONRPCMessageSchema } from '../types.js';
  2. const SUBPROTOCOL = 'mcp';
  3. /**
  4. * Client transport for WebSocket: this will connect to a server over the WebSocket protocol.
  5. */
  6. export class WebSocketClientTransport {
  7. constructor(url) {
  8. this._url = url;
  9. }
  10. start() {
  11. if (this._socket) {
  12. throw new Error('WebSocketClientTransport already started! If using Client class, note that connect() calls start() automatically.');
  13. }
  14. return new Promise((resolve, reject) => {
  15. this._socket = new WebSocket(this._url, SUBPROTOCOL);
  16. this._socket.onerror = event => {
  17. const error = 'error' in event ? event.error : new Error(`WebSocket error: ${JSON.stringify(event)}`);
  18. reject(error);
  19. this.onerror?.(error);
  20. };
  21. this._socket.onopen = () => {
  22. resolve();
  23. };
  24. this._socket.onclose = () => {
  25. this.onclose?.();
  26. };
  27. this._socket.onmessage = (event) => {
  28. let message;
  29. try {
  30. message = JSONRPCMessageSchema.parse(JSON.parse(event.data));
  31. }
  32. catch (error) {
  33. this.onerror?.(error);
  34. return;
  35. }
  36. this.onmessage?.(message);
  37. };
  38. });
  39. }
  40. async close() {
  41. this._socket?.close();
  42. }
  43. send(message) {
  44. return new Promise((resolve, reject) => {
  45. if (!this._socket) {
  46. reject(new Error('Not connected'));
  47. return;
  48. }
  49. this._socket?.send(JSON.stringify(message));
  50. resolve();
  51. });
  52. }
  53. }
  54. //# sourceMappingURL=websocket.js.map