terriajs
Version:
Geospatial data visualization platform.
296 lines (257 loc) • 9.42 kB
JavaScript
'use strict';
/*global require*/
var arraysAreEqual = require('../Core/arraysAreEqual');
var defaultValue = require('terriajs-cesium/Source/Core/defaultValue');
var defined = require('terriajs-cesium/Source/Core/defined');
var defineProperties = require('terriajs-cesium/Source/Core/defineProperties');
var DeveloperError = require('terriajs-cesium/Source/Core/DeveloperError');
var knockout = require('terriajs-cesium/Source/ThirdParty/knockout');
var runLater = require('../Core/runLater');
var serializeToJson = require('../Core/serializeToJson');
var updateFromJson = require('../Core/updateFromJson');
var TerriaError = require('../Core/TerriaError');
/**
* A parameter to a {@link CatalogFunction}.
*
* @alias FunctionParameter
* @constructor
* @abstract
*
* @param {Object} [options] Object with the following properties:
* @param {Terria} options.terria The Terria instance.
* @param {CatalogFunction} options.catalogFunction The function that this is a parameter to.
* @param {String} options.id The unique ID of this parameter.
* @param {String} [options.name] The name of this parameter. If not specified, the ID is used as the name.
* @param {String} [options.description] The description of the parameter.
* @param {Boolean} [options.isRequired] True if this parameter is required, false if it is optional.
* @param {Object} [options.value] The initial value of the parameter.
*/
var FunctionParameter = function(options) {
if (!defined(options) || !defined(options.terria)) {
throw new DeveloperError('options.terria is required.');
}
if (!defined(options.catalogFunction)) {
throw new DeveloperError('options.catalogFunction is required.');
}
if (!defined(options.id)) {
throw new DeveloperError('options.id is required.');
}
this._terria = options.terria;
this._catalogFunction = options.catalogFunction;
this._id = options.id;
this._loadingPromise = undefined;
this._lastLoadInfluencingValues = undefined;
/**
* Gets or sets a value indicating whether the parameter is currently loading. This property
* is observable.
* @type {Boolean}
*/
this.isLoading = false;
/**
* Gets or sets the name of the parameter.
* @type {String}
*/
this.name = defaultValue(options.name, options.id);
/**
* Gets or sets the description of the parameter.
* @type {String}
*/
this.description = options.description;
/**
* Gets or sets a value indicating whether this parameter is required.
* @type {Boolean}
* @default false
*/
this.isRequired = defaultValue(options.isRequired, false);
/**
* A converter that can be used to convert this parameter for use with a {@link CatalogFunction}.
* The actual type and content of this property is defined by the catalog function.
* @type {Any}
*/
this.converter = undefined;
/**
* Gets or sets the formatter (from the set defined by {@link FunctionParameter#availableFormatters})
* to use to format this parameter to pass to the {@link CatalogFunction}.
* @type {String}
*/
this.formatter = 'default';
/**
* Gets the default value for this parameter, or undefined if there is no default value.
*/
this._defaultValue = options.defaultValue;
/**
* Gets or sets the current value of this parameter.
*/
this.value = options.value;
knockout.track(this, ['_value', 'formatter', '_defaultValue']);
/**
* Gets or sets the current value of this parameter.
* @member {*} value
* @memberof FunctionParameter.prototype
*/
knockout.defineProperty(this, 'value', {
get: FunctionParameter.defaultValueGetter,
set: FunctionParameter.defaultValueSetter
});
/**
* Gets the default value for this parameter, or undefined if there is no default value.
* @member {*} defaultValue
* @memberof FunctionParameter.prototype
*/
knockout.defineProperty(this, 'defaultValue', {
get: function() { return this._defaultValue; },
set: function(value) { this._defaultValue = value; }
});
};
FunctionParameter.defaultValueGetter = function() {
if (!defined(this._value)) {
return this.defaultValue;
}
return this._value;
};
FunctionParameter.defaultValueSetter = function(value) {
this._value = value;
};
defineProperties(FunctionParameter.prototype, {
/**
* Gets the type of this parameter.
* @memberof FunctionParameter.prototype
* @type {String}
*/
type: {
get: function() {
throw new DeveloperError('FunctionParameter.type must be overridden in derived classes.');
}
},
/**
* Gets the Terria instance associated with this parameter.
* @memberof FunctionParameter.prototype
* @type {Terria}
*/
terria: {
get: function() {
return this._terria;
}
},
/**
* Gets the function to which this is a parameter.
* @memberof FunctionParameter.prototype
* @type {CatalogFunction}
*/
catalogFunction: {
get: function() {
return this._catalogFunction;
}
},
/**
* Gets the ID of the parameter.
* @memberof FunctionParameter.prototype
* @type {String}
*/
id: {
get: function() {
return this._id;
}
},
/**
* Gets the formatters that are available to format the parameter's value.
* @memberof FunctionParameter.prototype
*/
availableFormatters: {
get: function() {
if (this.constructor && this.constructor.AvailableFormatters) {
return this.constructor.AvailableFormatters;
} else {
return {
default: this.formatValueAsString.bind(this)
};
}
}
}
});
FunctionParameter.prototype.load = function() {
if (!defined(this._load)) {
// No loading required.
return undefined;
}
if (defined(this._loadingPromise)) {
// Load already in progress.
return this._loadingPromise;
}
var loadInfluencingValues = [];
if (defined(this._getValuesThatInfluenceLoad)) {
loadInfluencingValues = this._getValuesThatInfluenceLoad();
}
if (arraysAreEqual(loadInfluencingValues, this._lastLoadInfluencingValues)) {
// Already loaded, and nothing has changed to force a re-load.
return undefined;
}
this.isLoading = true;
var that = this;
this._loadingPromise = runLater(function() {
that._lastLoadInfluencingValues = [];
if (defined(that._getValuesThatInfluenceLoad)) {
that._lastLoadInfluencingValues = that._getValuesThatInfluenceLoad();
}
return that._load();
}).then(function() {
that._loadingPromise = undefined;
that.isLoading = false;
}).otherwise(function(e) {
that._lastLoadInfluencingValues = undefined;
that._loadingPromise = undefined;
that.isLoading = false;
throw e;
});
return this._loadingPromise;
};
/**
* Represents value as string.
* @param {Object} [value] Value to format as string. If not specified, {@link FunctionParameter#value} is used.
* @return {String} String representation of the value.
*/
FunctionParameter.prototype.formatValueAsString = function(value) {
value = defaultValue(value, this._value);
return defined(value) ? value.toString() : '-';
};
/**
* Formats this value to pass to a service. The format is controlled by the
* {@link FunctionParameter#formatter} property.
*
* @param {Object} [value] Value to format as string. If not specified, {@link FunctionParameter#value} is used.
* @return {Any} The formatted value.
*/
FunctionParameter.prototype.formatForService = function(value) {
const formatter = this.availableFormatters[this.formatter];
if (!formatter) {
throw new TerriaError({
sender: this,
title: 'Unknown formatter',
message: `The function parameter formatter ${this.formatter} is unknown.\n\n` +
'Valid formatters are:\n\n' +
' * ' + Object.keys(this.availableFormatters).join('\n * ')
});
}
value = defaultValue(value, this._value);
return formatter(value);
};
/**
* Updates the function parameter from a JSON object-literal description of it.
*
* @param {Object} json The JSON description. The JSON should be in the form of an object literal, not a string.
* @returns {Promise} A promise that resolves when the update is complete.
*/
FunctionParameter.prototype.updateFromJson = function(json) {
return updateFromJson(this, json);
};
/**
* Serializes the data item to JSON.
*
* @return {Object} The serialized JSON object-literal.
*/
FunctionParameter.prototype.serializeToJson = function() {
var result = serializeToJson(this);
result.type = this.type;
return result;
};
module.exports = FunctionParameter;