@zlooun/exceljs
Version:
Fixes the problem with writing a file using streams and not using RAM based on 'exeljs'
89 lines (85 loc) • 5.82 kB
JavaScript
;
function _typeof(obj) { "@babel/helpers - typeof"; return _typeof = "function" == typeof Symbol && "symbol" == typeof Symbol.iterator ? function (obj) { return typeof obj; } : function (obj) { return obj && "function" == typeof Symbol && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }, _typeof(obj); }
function _classCallCheck(instance, Constructor) { if (!(instance instanceof Constructor)) { throw new TypeError("Cannot call a class as a function"); } }
function _defineProperties(target, props) { for (var i = 0; i < props.length; i++) { var descriptor = props[i]; descriptor.enumerable = descriptor.enumerable || false; descriptor.configurable = true; if ("value" in descriptor) descriptor.writable = true; Object.defineProperty(target, _toPropertyKey(descriptor.key), descriptor); } }
function _createClass(Constructor, protoProps, staticProps) { if (protoProps) _defineProperties(Constructor.prototype, protoProps); if (staticProps) _defineProperties(Constructor, staticProps); Object.defineProperty(Constructor, "prototype", { writable: false }); return Constructor; }
function _toPropertyKey(arg) { var key = _toPrimitive(arg, "string"); return _typeof(key) === "symbol" ? key : String(key); }
function _toPrimitive(input, hint) { if (_typeof(input) !== "object" || input === null) return input; var prim = input[Symbol.toPrimitive]; if (prim !== undefined) { var res = prim.call(input, hint || "default"); if (_typeof(res) !== "object") return res; throw new TypeError("@@toPrimitive must return a primitive value."); } return (hint === "string" ? String : Number)(input); }
function _inherits(subClass, superClass) { if (typeof superClass !== "function" && superClass !== null) { throw new TypeError("Super expression must either be null or a function"); } subClass.prototype = Object.create(superClass && superClass.prototype, { constructor: { value: subClass, writable: true, configurable: true } }); Object.defineProperty(subClass, "prototype", { writable: false }); if (superClass) _setPrototypeOf(subClass, superClass); }
function _setPrototypeOf(o, p) { _setPrototypeOf = Object.setPrototypeOf ? Object.setPrototypeOf.bind() : function _setPrototypeOf(o, p) { o.__proto__ = p; return o; }; return _setPrototypeOf(o, p); }
function _createSuper(Derived) { var hasNativeReflectConstruct = _isNativeReflectConstruct(); return function _createSuperInternal() { var Super = _getPrototypeOf(Derived), result; if (hasNativeReflectConstruct) { var NewTarget = _getPrototypeOf(this).constructor; result = Reflect.construct(Super, arguments, NewTarget); } else { result = Super.apply(this, arguments); } return _possibleConstructorReturn(this, result); }; }
function _possibleConstructorReturn(self, call) { if (call && (_typeof(call) === "object" || typeof call === "function")) { return call; } else if (call !== void 0) { throw new TypeError("Derived constructors may only return object or undefined"); } return _assertThisInitialized(self); }
function _assertThisInitialized(self) { if (self === void 0) { throw new ReferenceError("this hasn't been initialised - super() hasn't been called"); } return self; }
function _isNativeReflectConstruct() { if (typeof Reflect === "undefined" || !Reflect.construct) return false; if (Reflect.construct.sham) return false; if (typeof Proxy === "function") return true; try { Boolean.prototype.valueOf.call(Reflect.construct(Boolean, [], function () {})); return true; } catch (e) { return false; } }
function _getPrototypeOf(o) { _getPrototypeOf = Object.setPrototypeOf ? Object.getPrototypeOf.bind() : function _getPrototypeOf(o) { return o.__proto__ || Object.getPrototypeOf(o); }; return _getPrototypeOf(o); }
var events = require('events');
// =============================================================================
// StutteredPipe - Used to slow down streaming so GC can get a look in
var StutteredPipe = /*#__PURE__*/function (_events$EventEmitter) {
_inherits(StutteredPipe, _events$EventEmitter);
var _super = _createSuper(StutteredPipe);
function StutteredPipe(readable, writable, options) {
var _this;
_classCallCheck(this, StutteredPipe);
_this = _super.call(this);
options = options || {};
_this.readable = readable;
_this.writable = writable;
_this.bufSize = options.bufSize || 16384;
_this.autoPause = options.autoPause || false;
_this.paused = false;
_this.eod = false;
_this.scheduled = null;
readable.on('end', function () {
_this.eod = true;
writable.end();
});
// need to have some way to communicate speed of stream
// back from the consumer
readable.on('readable', function () {
if (!_this.paused) {
_this.resume();
}
});
_this._schedule();
return _this;
}
_createClass(StutteredPipe, [{
key: "pause",
value: function pause() {
this.paused = true;
}
}, {
key: "resume",
value: function resume() {
if (!this.eod) {
if (this.scheduled !== null) {
clearImmediate(this.scheduled);
}
this._schedule();
}
}
}, {
key: "_schedule",
value: function _schedule() {
var _this2 = this;
this.scheduled = setImmediate(function () {
_this2.scheduled = null;
if (!_this2.eod && !_this2.paused) {
var data = _this2.readable.read(_this2.bufSize);
if (data && data.length) {
_this2.writable.write(data);
if (!_this2.paused && !_this2.autoPause) {
_this2._schedule();
}
} else if (!_this2.paused) {
_this2._schedule();
}
}
});
}
}]);
return StutteredPipe;
}(events.EventEmitter);
module.exports = StutteredPipe;
//# sourceMappingURL=stuttered-pipe.js.map