openmct/example/generator/src/generatorWorker.js
Henry 976333d7f7 [Tables] Support for subscriptions from new Telemetry API
Historical and real-time data flowing

Added formatting, and limits. Support telemetry objects themselves and not just composition of telemetry objects

Apply default time range if none supplied (15 minutes)
2017-02-10 14:21:26 -08:00

155 lines
4.7 KiB
JavaScript

/*****************************************************************************
* Open MCT, Copyright (c) 2014-2016, United States Government
* as represented by the Administrator of the National Aeronautics and Space
* Administration. All rights reserved.
*
* Open MCT is licensed under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0.
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
* License for the specific language governing permissions and limitations
* under the License.
*
* Open MCT includes source code licensed under additional open source
* licenses. See the Open Source Licenses file (LICENSES.md) included with
* this source code distribution or the Licensing information page available
* at runtime from the About dialog for additional information.
*****************************************************************************/
/*global self*/
(function () {
var FIFTEEN_MINUTES = 15 * 60 * 1000;
var handlers = {
subscribe: onSubscribe,
unsubscribe: onUnsubscribe,
request: onRequest
};
var subscriptions = {};
function workSubscriptions(timestamp) {
var now = Date.now();
var nextWork = Math.min.apply(Math, Object.values(subscriptions).map(function (subscription) {
return subscription(now);
}));
var wait = nextWork - now;
if (wait < 0) {
wait = 0;
}
if (Number.isFinite(wait)) {
setTimeout(workSubscriptions, wait);
}
}
function onSubscribe(message) {
var data = message.data;
var start = Date.now();
var step = 1000 / data.dataRateInHz;
var nextStep = start - (start % step) + step;
function work(now) {
while (nextStep < now) {
self.postMessage({
id: message.id,
data: {
utc: nextStep,
yesterday: nextStep - 60*60*24*1000,
delta: 60*60*24*1000,
sin: sin(nextStep, data.period, data.amplitude, data.offset),
cos: cos(nextStep, data.period, data.amplitude, data.offset)
}
});
nextStep += step;
}
return nextStep;
}
subscriptions[message.id] = work;
workSubscriptions();
}
function onUnsubscribe(message) {
delete subscriptions[message.data.id];
}
function onRequest(message) {
var data = message.data;
if (data.end == undefined) {
data.end = Date.now();
}
if (data.start == undefined){
data.start = data.end - FIFTEEN_MINUTES;
}
var now = Date.now();
var start = data.start;
var end = data.end > now ? now : data.end;
var amplitude = data.amplitude;
var period = data.period;
var offset = data.offset;
var dataRateInHz = data.dataRateInHz;
var step = 1000 / dataRateInHz;
var nextStep = start - (start % step) + step;
var data = [];
for (; nextStep < end; nextStep += step) {
data.push({
utc: nextStep,
yesterday: nextStep - 60*60*24*1000,
delta: 60*60*24*1000,
sin: sin(nextStep, period, amplitude, offset),
cos: cos(nextStep, period, amplitude, offset)
});
}
self.postMessage({
id: message.id,
data: data
});
}
function cos(timestamp, period, amplitude, offset) {
return amplitude *
Math.cos(timestamp / period / 1000 * Math.PI * 2) + offset;
}
function sin(timestamp, period, amplitude, offset) {
return amplitude *
Math.sin(timestamp / period / 1000 * Math.PI * 2) + offset;
}
function sendError(error, message) {
self.postMessage({
error: error.name + ': ' + error.message,
message: message,
id: message.id
});
}
self.onmessage = function handleMessage(event) {
var message = event.data;
var handler = handlers[message.request];
if (!handler) {
sendError(new Error('unknown message type'), message);
} else {
try {
handler(message);
} catch (e) {
sendError(e, message);
}
}
};
}());