Method send

packages/engine.io/lib/transports/polling.ts:221–247

(packets: Packet[])

  }

  send(packets: Packet[]) {
    this.writable = false;

    if (this.shouldClose) {
      debug("appending close packet to payload");
      packets.push({ type: "close" });
      this.shouldClose();
      this.shouldClose = null;
    }

    const doWrite = (data: string) => {
      const compress = packets.some((packet) => {
        return packet.options && packet.options.compress;
      });
      this.write(data, { compress });
    };

    if (this.protocol === 3) {
      (this.parser as typeof parser_v3).encodePayload(
        packets,
        this.supportsBinary,
        doWrite,
      );
    } else {
      (this.parser as typeof parser_v4).encodePayload(packets, doWrite);
    }
  }

  /**
   * Writes data as response to poll request.