websocket.js 2.7 KB

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  1. "use strict";
  2. Object.defineProperty(exports, "__esModule", { value: true });
  3. exports.WebSocket = void 0;
  4. const transport_1 = require("../transport");
  5. const debug_1 = require("debug");
  6. const debug = (0, debug_1.default)("engine:ws");
  7. class WebSocket extends transport_1.Transport {
  8. /**
  9. * WebSocket transport
  10. *
  11. * @param {http.IncomingMessage}
  12. * @api public
  13. */
  14. constructor(req) {
  15. super(req);
  16. this.socket = req.websocket;
  17. this.socket.on("message", (data, isBinary) => {
  18. const message = isBinary ? data : data.toString();
  19. debug('received "%s"', message);
  20. super.onData(message);
  21. });
  22. this.socket.once("close", this.onClose.bind(this));
  23. this.socket.on("error", this.onError.bind(this));
  24. this.writable = true;
  25. this.perMessageDeflate = null;
  26. }
  27. /**
  28. * Transport name
  29. *
  30. * @api public
  31. */
  32. get name() {
  33. return "websocket";
  34. }
  35. /**
  36. * Advertise upgrade support.
  37. *
  38. * @api public
  39. */
  40. get handlesUpgrades() {
  41. return true;
  42. }
  43. /**
  44. * Advertise framing support.
  45. *
  46. * @api public
  47. */
  48. get supportsFraming() {
  49. return true;
  50. }
  51. /**
  52. * Writes a packet payload.
  53. *
  54. * @param {Array} packets
  55. * @api private
  56. */
  57. send(packets) {
  58. const packet = packets.shift();
  59. if (typeof packet === "undefined") {
  60. this.writable = true;
  61. this.emit("drain");
  62. return;
  63. }
  64. // always creates a new object since ws modifies it
  65. const opts = {};
  66. if (packet.options) {
  67. opts.compress = packet.options.compress;
  68. }
  69. const send = data => {
  70. if (this.perMessageDeflate) {
  71. const len = "string" === typeof data ? Buffer.byteLength(data) : data.length;
  72. if (len < this.perMessageDeflate.threshold) {
  73. opts.compress = false;
  74. }
  75. }
  76. debug('writing "%s"', data);
  77. this.writable = false;
  78. this.socket.send(data, opts, err => {
  79. if (err)
  80. return this.onError("write error", err.stack);
  81. this.send(packets);
  82. });
  83. };
  84. if (packet.options && typeof packet.options.wsPreEncoded === "string") {
  85. send(packet.options.wsPreEncoded);
  86. }
  87. else {
  88. this.parser.encodePacket(packet, this.supportsBinary, send);
  89. }
  90. }
  91. /**
  92. * Closes the transport.
  93. *
  94. * @api private
  95. */
  96. doClose(fn) {
  97. debug("closing");
  98. this.socket.close();
  99. fn && fn();
  100. }
  101. }
  102. exports.WebSocket = WebSocket;