simpleddp-node
Version:
The aim of this library is to simplify the process of working with meteor server over DDP protocol using external JS environments
69 lines (68 loc) • 1.91 kB
JavaScript
"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.ddpReducer = void 0;
const ddpOnChange_js_1 = require("./ddpOnChange.js");
/**
* A reducer class for a reactive document.
* @constructor
*/
class ddpReducer {
_ddpReactiveCollectionInstance;
_reducer;
_started = false;
_data = { result: null };
_tickers = [];
_initialValue;
constructor(ddpReactiveCollectionInstance, reducer, initialValue) {
this._ddpReactiveCollectionInstance = ddpReactiveCollectionInstance;
this._reducer = reducer;
this._initialValue = initialValue;
this.start();
}
/**
* Forcibly reduces reactive data.
*/
doReduce() {
if (this._started) {
this._data.result = this._ddpReactiveCollectionInstance.data().reduce(this._reducer, this._initialValue);
this._tickers.forEach((ticker) => {
ticker(this.data().result);
});
}
}
/**
* Starts reactiveness for the reduced value of the collection.
* This method is being called on instance creation.
*/
start() {
if (!this._started) {
this.doReduce();
this._ddpReactiveCollectionInstance._activateReducer(this);
this._started = true;
}
}
/**
* Stops reactiveness.
*/
stop() {
if (this._started) {
this._ddpReactiveCollectionInstance._deactivateReducer(this);
this._started = false;
}
}
/**
* Returns reactive reduce.
*/
data() {
return this._data;
}
/**
* Runs a function every time a change occurs.
* @param {Function} f - Function which recieves a reduced value at each change.
*/
onChange(f) {
const self = this;
return (0, ddpOnChange_js_1.ddpOnChange)(f, self, '_tickers');
}
}
exports.ddpReducer = ddpReducer;