aimpress-chatbot/node_modules/botframework-streaming/lib/webSocket/webSocketTransport.js

"use strict";
/**
 * @module botframework-streaming
 */
/**
 * Copyright (c) Microsoft Corporation. All rights reserved.
 * Licensed under the MIT License.
 */
var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
    return new (P || (P = Promise))(function (resolve, reject) {
        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
        step((generator = generator.apply(thisArg, _arguments || [])).next());
    });
};
Object.defineProperty(exports, "__esModule", { value: true });
exports.WebSocketTransport = void 0;
/**
 * Web socket based transport.
 */
class WebSocketTransport {
    /**
     * Creates a new instance of the [WebSocketTransport](xref:botframework-streaming.WebSocketTransport) class.
     *
     * @param ws The ISocket to build this transport on top of.
     */
    constructor(ws) {
        this.ws = ws;
        this._queue = [];
        this._activeOffset = 0;
        this._activeReceiveCount = 0;
        this.ws.setOnMessageHandler((data) => {
            this.onReceive(data);
        });
        this.ws.setOnErrorHandler((err) => {
            this.onError(err);
        });
        this.ws.setOnCloseHandler(() => {
            this.onClose();
        });
    }
    /**
     * Sends the given buffer out over the socket's connection.
     *
     * @param buffer The buffered data to send out over the connection.
     * @returns A number indicating the length of the sent data if the data was successfully sent, otherwise 0.
     */
    send(buffer) {
        var _a;
        if ((_a = this.ws) === null || _a === void 0 ? void 0 : _a.isConnected) {
            this.ws.write(buffer);
            return buffer.length;
        }
        return 0;
    }
    /**
     * Returns true if the transport is connected to a socket.
     *
     * @returns `true` if the the transport is connected and ready to send data, `false` otherwise.
     */
    get isConnected() {
        var _a;
        return !!((_a = this.ws) === null || _a === void 0 ? void 0 : _a.isConnected);
    }
    /**
     * Close the socket this transport is connected to.
     */
    close() {
        var _a;
        if ((_a = this.ws) === null || _a === void 0 ? void 0 : _a.isConnected) {
            this.ws.close();
        }
    }
    /**
     * Attempt to receive incoming data from the connected socket.
     *
     * @param count The number of bytes to attempt to receive.
     * @returns A buffer populated with the received data.
     */
    receive(count) {
        return __awaiter(this, void 0, void 0, function* () {
            if (this._activeReceiveResolve) {
                throw new Error('Cannot call receive more than once before it has returned.');
            }
            this._activeReceiveCount = count;
            const promise = new Promise((resolve, reject) => {
                this._activeReceiveResolve = resolve;
                this._activeReceiveReject = reject;
            });
            this.trySignalData();
            return promise;
        });
    }
    /**
     * Sets the transport to attempt to receive incoming data that has not yet arrived.
     *
     * @param data A buffer to store incoming data in.
     */
    onReceive(data) {
        if (this._queue && data && data.byteLength > 0) {
            this._queue.push(Buffer.from(data));
            this.trySignalData();
        }
    }
    onClose() {
        if (this._activeReceiveReject) {
            this._activeReceiveReject(new Error('Socket was closed.'));
        }
        this._active = null;
        this._activeOffset = 0;
        this._activeReceiveResolve = null;
        this._activeReceiveReject = null;
        this._activeReceiveCount = 0;
        this.ws = null;
    }
    onError(err) {
        if (this._activeReceiveReject) {
            this._activeReceiveReject(err);
        }
        this.onClose();
    }
    trySignalData() {
        if (this._activeReceiveResolve) {
            if (!this._active && this._queue.length > 0) {
                this._active = this._queue.shift();
                this._activeOffset = 0;
            }
            if (this._active) {
                if (this._activeOffset === 0 && this._active.length === this._activeReceiveCount) {
                    // can send the entire _active buffer
                    const buffer = this._active;
                    this._active = null;
                    this._activeReceiveResolve(buffer);
                }
                else {
                    // create a Buffer.from and copy some of the contents into it
                    const available = Math.min(this._activeReceiveCount, this._active.length - this._activeOffset);
                    const buffer = Buffer.alloc(available);
                    this._active.copy(buffer, 0, this._activeOffset, this._activeOffset + available);
                    this._activeOffset += available;
                    // if we used all of active, set it to undefined
                    if (this._activeOffset >= this._active.length) {
                        this._active = null;
                        this._activeOffset = 0;
                    }
                    this._activeReceiveResolve(buffer);
                }
                this._activeReceiveCount = 0;
                this._activeReceiveReject = null;
                this._activeReceiveResolve = null;
            }
        }
    }
}
exports.WebSocketTransport = WebSocketTransport;
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