115 lines
4.3 KiB
JavaScript
115 lines
4.3 KiB
JavaScript
/*****************************************************************************
|
|
* Open MCT Web, Copyright (c) 2014-2015, United States Government
|
|
* as represented by the Administrator of the National Aeronautics and Space
|
|
* Administration. All rights reserved.
|
|
*
|
|
* Open MCT Web 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 Web 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 define*/
|
|
|
|
/**
|
|
* This bundle provides infrastructure and utility services for handling
|
|
* telemetry data.
|
|
* @namespace platform/telemetry
|
|
*/
|
|
define(
|
|
[],
|
|
function () {
|
|
"use strict";
|
|
|
|
/**
|
|
* Request telemetry data.
|
|
* @param {TelemetryRequest[]} requests and array of
|
|
* requests to be handled
|
|
* @returns {Promise} a promise for telemetry data
|
|
* which may (or may not, depending on
|
|
* availability) satisfy the requests
|
|
* @method TelemetryService#requestTelemetry
|
|
*/
|
|
/**
|
|
* Subscribe to streaming updates to telemetry data.
|
|
* The provided callback will be invoked as new
|
|
* telemetry becomes available; as an argument, it
|
|
* will receive an object of key-value pairs, where
|
|
* keys are source identifiers and values are objects
|
|
* of key-value pairs, where keys are point identifiers
|
|
* and values are TelemetrySeries objects containing
|
|
* the latest streaming telemetry.
|
|
* @param {Function} callback the callback to invoke
|
|
* @param {TelemetryRequest[]} requests an array of
|
|
* requests to be subscribed upon
|
|
* @returns {Function} a function which can be called
|
|
* to unsubscribe
|
|
* @method TelmetryService#subscribe
|
|
*/
|
|
|
|
/**
|
|
* A telemetry aggregator makes many telemetry providers
|
|
* appear as one.
|
|
*
|
|
* @memberof platform/telemetry
|
|
* @constructor
|
|
*/
|
|
function TelemetryAggregator($q, telemetryProviders) {
|
|
this.$q = $q;
|
|
this.telemetryProviders = telemetryProviders;
|
|
}
|
|
|
|
// Merge the results from many providers into one
|
|
// result object.
|
|
function mergeResults(results) {
|
|
var merged = {};
|
|
|
|
results.forEach(function (result) {
|
|
Object.keys(result).forEach(function (k) {
|
|
merged[k] = result[k];
|
|
});
|
|
});
|
|
|
|
return merged;
|
|
}
|
|
|
|
// Request telemetry from all providers; once they've
|
|
// responded, merge the results into one result object.
|
|
TelemetryAggregator.prototype.requestTelemetry = function (requests) {
|
|
return this.$q.all(this.telemetryProviders.map(function (provider) {
|
|
return provider.requestTelemetry(requests);
|
|
})).then(mergeResults);
|
|
};
|
|
|
|
// Subscribe to updates from all providers
|
|
TelemetryAggregator.prototype.subscribe = function (callback, requests) {
|
|
var unsubscribes = this.telemetryProviders.map(function (provider) {
|
|
return provider.subscribe(callback, requests);
|
|
});
|
|
|
|
// Return an unsubscribe function that invokes unsubscribe
|
|
// for all providers.
|
|
return function () {
|
|
unsubscribes.forEach(function (unsubscribe) {
|
|
if (unsubscribe) {
|
|
unsubscribe();
|
|
}
|
|
});
|
|
};
|
|
};
|
|
|
|
|
|
return TelemetryAggregator;
|
|
}
|
|
);
|