streaming/timeout.js

Transforms and other streaming helpers

"use strict";
var __extends = (this && this.__extends) || (function () {
    var extendStatics = function (d, b) {
        extendStatics = Object.setPrototypeOf ||
            ({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
            function (d, b) { for (var p in b) if (Object.prototype.hasOwnProperty.call(b, p)) d[p] = b[p]; };
        return extendStatics(d, b);
    };
    return function (d, b) {
        if (typeof b !== "function" && b !== null)
            throw new TypeError("Class extends value " + String(b) + " is not a constructor or null");
        extendStatics(d, b);
        function __() { this.constructor = d; }
        d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
    };
})();
Object.defineProperty(exports, "__esModule", { value: true });
exports.Timeout = void 0;
var stream_1 = require("stream");
/**
Timeout is mostly a PassThrough (identity) stream, but will throw an error if
a period of `timeoutMilliseconds` elapses without seeing any new data.
*/
var Timeout = /** @class */ (function (_super) {
    __extends(Timeout, _super);
    function Timeout(timeoutSeconds, options) {
        var _this = _super.call(this, options) || this;
        // if (timeoutSeconds === undefined) {
        //   throw new Error('new Timeout(timeoutSeconds): timeoutSeconds is a required parameter.');
        // }
        _this.timeoutMilliseconds = timeoutSeconds * 1000;
        setInterval(function () { return _this._check(); }, _this.timeoutMilliseconds);
        return _this;
    }
    Timeout.prototype._check = function () {
        // millisecondsSinceLast: milliseconds since we last saw some incoming data
        var millisecondsSinceLast = (new Date()).getTime() - this.lastChunkReceived;
        if (millisecondsSinceLast > this.timeoutMilliseconds) {
            this.emit('error', new Error("Timed out: ".concat(millisecondsSinceLast, "ms")));
        }
    };
    Timeout.prototype._transform = function (chunk, encoding, callback) {
        this.lastChunkReceived = (new Date()).getTime();
        this.push(chunk);
        callback();
    };
    Timeout.prototype._flush = function (callback) {
        // don't clear the interval
        callback();
    };
    return Timeout;
}(stream_1.Transform));
exports.Timeout = Timeout;