@jsreport/exceljs
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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 ownKeys(object, enumerableOnly) { var keys = Object.keys(object); if (Object.getOwnPropertySymbols) { var symbols = Object.getOwnPropertySymbols(object); enumerableOnly && (symbols = symbols.filter(function (sym) { return Object.getOwnPropertyDescriptor(object, sym).enumerable; })), keys.push.apply(keys, symbols); } return keys; }
function _objectSpread(target) { for (var i = 1; i < arguments.length; i++) { var source = null != arguments[i] ? arguments[i] : {}; i % 2 ? ownKeys(Object(source), !0).forEach(function (key) { _defineProperty(target, key, source[key]); }) : Object.getOwnPropertyDescriptors ? Object.defineProperties(target, Object.getOwnPropertyDescriptors(source)) : ownKeys(Object(source)).forEach(function (key) { Object.defineProperty(target, key, Object.getOwnPropertyDescriptor(source, key)); }); } return target; }
function _defineProperty(obj, key, value) { if (key in obj) { Object.defineProperty(obj, key, { value: value, enumerable: true, configurable: true, writable: true }); } else { obj[key] = value; } return obj; }
function asyncGeneratorStep(gen, resolve, reject, _next, _throw, key, arg) { try { var info = gen[key](arg); var value = info.value; } catch (error) { reject(error); return; } if (info.done) { resolve(value); } else { Promise.resolve(value).then(_next, _throw); } }
function _asyncToGenerator(fn) { return function () { var self = this, args = arguments; return new Promise(function (resolve, reject) { var gen = fn.apply(self, args); function _next(value) { asyncGeneratorStep(gen, resolve, reject, _next, _throw, "next", value); } function _throw(err) { asyncGeneratorStep(gen, resolve, reject, _next, _throw, "throw", err); } _next(undefined); }); }; }
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, 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 _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 || 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 : function _getPrototypeOf(o) { return o.__proto__ || Object.getPrototypeOf(o); }; return _getPrototypeOf(o); }
var _require = require('events'),
EventEmitter = _require.EventEmitter;
var utils = require('./utils'); // =============================================================================
// FlowControl - Used to slow down streaming to manageable speed
// Implements a subset of Stream.Duplex: pipe() and write()
var FlowControl = /*#__PURE__*/function (_EventEmitter) {
_inherits(FlowControl, _EventEmitter);
var _super = _createSuper(FlowControl);
function FlowControl(options) {
var _this;
_classCallCheck(this, FlowControl);
_this = _super.call(this);
_this.options = options = options || {}; // Buffer queue
_this.queue = []; // Consumer streams
_this.pipes = []; // Down-stream flow-control instances
_this.children = []; // Up-stream flow-control instances
_this.parent = options.parent; // Ensure we don't flush more than once at a time
_this.flushing = false; // determine timeout for flow control delays
if (options.gc) {
var _options = options,
gc = _options.gc;
if (gc.getTimeout) {
_this.getTimeout = gc.getTimeout;
} else {
// heap size below which we don't bother delaying
var threshold = gc.threshold !== undefined ? gc.threshold : 150000000; // convert from heapsize to ms timeout
var divisor = gc.divisor !== undefined ? gc.divisor : 500000;
_this.getTimeout = function () {
var memory = process.memoryUsage();
var heapSize = memory.heapTotal;
return heapSize < threshold ? 0 : Math.floor(heapSize / divisor);
};
}
} else {
_this.getTimeout = null;
}
return _this;
}
_createClass(FlowControl, [{
key: "name",
get: function get() {
return ['FlowControl', this.parent ? 'Child' : 'Root', this.corked ? 'corked' : 'open'].join(' ');
}
}, {
key: "corked",
get: function get() {
// We remain corked while we have children and at least one has data to consume
return this.children.length > 0 && this.children.some(function (child) {
return child.queue && child.queue.length;
});
}
}, {
key: "stem",
get: function get() {
// the decision to stem the incoming data depends on whether the children are corked
// and how many buffers we have backed up
return this.corked || !this.queue || this.queue.length > 2;
}
}, {
key: "_write",
value: function _write(dst, data, encoding) {
// Write to a single destination and return a promise
return new Promise(function (resolve, reject) {
dst.write(data, encoding, function (error) {
if (error) {
reject(error);
} else {
resolve();
}
});
});
}
}, {
key: "_pipe",
value: function () {
var _pipe2 = _asyncToGenerator( /*#__PURE__*/regeneratorRuntime.mark(function _callee(chunk) {
var _this2 = this;
var promises;
return regeneratorRuntime.wrap(function _callee$(_context) {
while (1) {
switch (_context.prev = _context.next) {
case 0:
// Write chunk to all pipes. A chunk with no data is the end
promises = [];
this.pipes.forEach(function (pipe) {
if (chunk.data) {
if (pipe.sync) {
pipe.stream.write(chunk.data, chunk.encoding);
} else {
promises.push(_this2._write(pipe.stream, chunk.data, chunk.encoding));
}
} else {
pipe.stream.end();
}
});
if (!promises.length) {
promises.push(Promise.resolve());
}
_context.next = 5;
return Promise.all(promises);
case 5:
try {
chunk.callback();
} catch (e) {// quietly ignore
}
case 6:
case "end":
return _context.stop();
}
}
}, _callee, this);
}));
function _pipe(_x) {
return _pipe2.apply(this, arguments);
}
return _pipe;
}()
}, {
key: "_animate",
value: function _animate() {
var count = 0;
var seq = ['|', '/', '-', '\\'];
var cr = "\x1B[0G"; // was '\033[0G'
return setInterval(function () {
process.stdout.write(seq[count++ % 4] + cr);
}, 100);
}
}, {
key: "_delay",
value: function _delay() {
var _this3 = this;
// in certain situations it may be useful to delay processing (e.g. for GC)
var timeout = this.getTimeout && this.getTimeout();
if (timeout) {
return new Promise(function (resolve) {
var anime = _this3._animate();
setTimeout(function () {
clearInterval(anime);
resolve();
}, timeout);
});
}
return Promise.resolve();
}
}, {
key: "_flush",
value: function () {
var _flush2 = _asyncToGenerator( /*#__PURE__*/regeneratorRuntime.mark(function _callee2() {
var _this4 = this;
return regeneratorRuntime.wrap(function _callee2$(_context2) {
while (1) {
switch (_context2.prev = _context2.next) {
case 0:
if (!(this.queue && !this.flushing && !this.corked)) {
_context2.next = 9;
break;
}
if (!this.queue.length) {
_context2.next = 8;
break;
}
this.flushing = true;
_context2.next = 5;
return this._delay();
case 5:
_context2.next = 7;
return this._pipe(this.queue.shift());
case 7:
setImmediate(function () {
_this4.flushing = false;
_this4._flush();
});
case 8:
if (!this.stem) {
// Signal up-stream that we're ready for more data
this.emit('drain');
}
case 9:
case "end":
return _context2.stop();
}
}
}, _callee2, this);
}));
function _flush() {
return _flush2.apply(this, arguments);
}
return _flush;
}()
}, {
key: "write",
value: function write(data, encoding, callback) {
// Called by up-stream pipe
if (encoding instanceof Function) {
callback = encoding;
encoding = 'utf8';
}
callback = callback || utils.nop;
if (!this.queue) {
throw new Error('Cannot write to stream after end');
} // Always queue chunks and then flush
this.queue.push({
data: data,
encoding: encoding,
callback: callback
});
this._flush(); // restrict further incoming data if we have backed up buffers or
// the children are still busy
var stemFlow = this.corked || this.queue.length > 3;
return !stemFlow;
}
}, {
key: "end",
value: function end() {
var _this5 = this;
// Signal from up-stream
this.queue.push({
callback: function callback() {
_this5.queue = null;
_this5.emit('finish');
}
});
this._flush();
}
}, {
key: "pipe",
value: function pipe(stream, options) {
options = options || {}; // some streams don't call callbacks
var sync = options.sync || false;
this.pipes.push({
stream: stream,
sync: sync
});
}
}, {
key: "unpipe",
value: function unpipe(stream) {
this.pipes = this.pipes.filter(function (pipe) {
return pipe.stream !== stream;
});
}
}, {
key: "createChild",
value: function createChild() {
var _this6 = this;
// Create a down-stream flow-control
var options = _objectSpread({
parent: this
}, this.options);
var child = new FlowControl(options);
this.children.push(child);
child.on('drain', function () {
// a child is ready for more
_this6._flush();
});
child.on('finish', function () {
// One child has finished its stream. Remove it and continue
_this6.children = _this6.children.filter(function (item) {
return item !== child;
});
_this6._flush();
});
return child;
}
}]);
return FlowControl;
}(EventEmitter);
module.exports = FlowControl;
//# sourceMappingURL=flow-control.js.map