'use strict';
/*global require*/
var clone = require('terriajs-cesium/Source/Core/clone');
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 freezeObject = require('terriajs-cesium/Source/Core/freezeObject');
var Resource = require('terriajs-cesium/Source/Core/Resource');
var when = require('terriajs-cesium/Source/ThirdParty/when');
var inherit = require('../Core/inherit');
var Metadata = require('./Metadata');
var TableCatalogItem = require('./TableCatalogItem');
var TerriaError = require('../Core/TerriaError');
var proxyCatalogItemUrl = require('./proxyCatalogItemUrl');
var readText = require('../Core/readText');
var TableStructure = require('../Map/TableStructure');
/**
* A {@link CatalogItem} representing CSV data.
*
* @alias CsvCatalogItem
* @constructor
* @extends TableCatalogItem
*
* @param {Terria} terria The Terria instance.
* @param {String} [url] The URL from which to retrieve the CSV data.
* @param {Object} [options] Initial values.
* @param {TableStyle} [options.tableStyle] An initial table style can be supplied if desired.
*/
var CsvCatalogItem = function(terria, url, options) {
TableCatalogItem.call(this, terria, url, options);
/**
* Gets or sets the character set of the data, which overrides the file information if present. Default is undefined.
* This property is observable.
* @type {String}
*/
this.charSet = undefined;
/**
* Some catalog items are created from other catalog items.
* Record here so that the user (eg. via "About this Dataset") can reference the source item.
* @type {CatalogItem}
*/
this.sourceCatalogItem = undefined;
/**
* Options for the value of the animation timeline at start. Valid options in config file are:
* initialTimeSource: "present" // closest to today's date
* initialTimeSource: "start" // start of time range of animation
* initialTimeSource: "end" // end of time range of animation
* initialTimeSource: An ISO8601 date e.g. "2015-08-08" // specified date or nearest if date is outside range
* @type {String}
*/
this.initialTimeSource = undefined;
};
inherit(TableCatalogItem, CsvCatalogItem);
defineProperties(CsvCatalogItem.prototype, {
/**
* Gets the type of data member represented by this instance.
* @memberOf CsvCatalogItem.prototype
* @type {String}
*/
type: {
get: function() {
return 'csv';
}
},
/**
* Gets a human-readable name for this type of data source, 'CSV'.
* @memberOf CsvCatalogItem.prototype
* @type {String}
*/
typeName: {
get: function() {
return 'Comma-Separated Values (CSV)';
}
},
/**
* Gets the metadata associated with this data source and the server that provided it, if applicable.
* @memberOf CsvCatalogItem.prototype
* @type {Metadata}
*/
metadata: { //TODO: return metadata if tableDataSource defined
get: function() {
var result = new Metadata();
result.isLoading = false;
result.dataSourceErrorMessage = 'This data source does not have any details available.';
result.serviceErrorMessage = 'This service does not have any details available.';
return result;
}
},
/**
* Gets the data source associated with this catalog item.
* @memberOf CsvCatalogItem.prototype
* @type {DataSource}
*/
dataSource: {
get: function() {
return this._dataSource;
}
}
});
CsvCatalogItem.defaultUpdaters = clone(TableCatalogItem.defaultUpdaters);
CsvCatalogItem.defaultUpdaters.sourceCatalogItem = function() {
// TODO: For now, don't update from JSON. Better to do it via an id?
};
freezeObject(CsvCatalogItem.defaultUpdaters);
CsvCatalogItem.defaultSerializers = clone(TableCatalogItem.defaultSerializers);
CsvCatalogItem.defaultSerializers.sourceCatalogItem = function() {
// TODO: For now, don't serialize. Can we do it via an id?
};
freezeObject(CsvCatalogItem.defaultSerializers);
/**
* Loads the TableStructure from a csv file.
*
* @param {CsvCatalogItem} item Item that tableDataSource is created for
* @param {String} csvString String in csv format.
* @return {Promise} A promise that resolves to true if it is a recognised format.
* @private
*/
function loadTableFromCsv(item, csvString) {
var tableStyle = item._tableStyle;
var options = {
idColumnNames: item.idColumns,
isSampled: item.isSampled,
initialTimeSource: item.initialTimeSource,
displayDuration: tableStyle.displayDuration,
replaceWithNullValues: tableStyle.replaceWithNullValues,
replaceWithZeroValues: tableStyle.replaceWithZeroValues,
columnOptions: tableStyle.columns // may contain per-column replacements for these
};
var tableStructure = new TableStructure(undefined, options);
tableStructure.loadFromCsv(csvString);
return item.initializeFromTableStructure(tableStructure);
}
/**
* Loads csv data from a URL into a (usually temporary) table structure.
* This is required by Chart.jsx for any non-csv format.
* @param {String} url The URL.
* @return {Promise} A promise which resolves to a table structure.
*/
CsvCatalogItem.prototype.loadIntoTableStructure = function(url) {
const item = this;
const tableStructure = new TableStructure();
// Note item is only used for its 'terria', 'forceProxy' and 'cacheDuration' properties
// (which are all defined on CatalogMember, the base class of CatalogItem).
return loadTextWithMime(proxyCatalogItemUrl(item, url, '0d')).then(tableStructure.loadFromCsv.bind(tableStructure));
};
/**
* Every <polling.seconds> seconds, if the csvItem is enabled,
* request data from the polling.url || url, and update/replace this._tableStructure.
*/
CsvCatalogItem.prototype.startPolling = function() {
const polling = this.polling;
if (defined(polling.seconds) && polling.seconds > 0) {
var item = this;
this._pollTimeout = setTimeout(function() {
if (item.isEnabled) {
item.loadIntoTableStructure(polling.url || item.url).then(function(newTable) {
// console.log('polled url', polling.url || item.url, newTable);
if (item._tableStructure.hasLatitudeAndLongitude !== newTable.hasLatitudeAndLongitude || item._tableStructure.columns.length !== newTable.columns.length) {
console.log('The newly polled data is incompatible with the old data.');
throw new DeveloperError('The newly polled data is incompatible with the old data.');
}
// Maintain active item and colors. Assume same column ordering for now.
item._tableStructure.columns.forEach(function(column, i) {
newTable.columns[i].isActive = column.isActive;
newTable.columns[i].color = column.color;
});
if (polling.replace) {
item._tableStructure.columns = newTable.columns;
} else {
if (defined(item.idColumns) && item.idColumns.length > 0) {
item._tableStructure.merge(newTable);
} else {
item._tableStructure.append(newTable);
}
}
});
}
// Note this means the timer keeps going even when you remove (disable) the item,
// but it doesn't actually request new data any more.
// If the item is re-enabled, the same timer just starts picking it up again.
item.startPolling();
}, polling.seconds * 1000);
}
};
CsvCatalogItem.prototype._load = function() {
var that = this;
if (defined(this.data)) {
return when(that.data, function(data) {
if (typeof Blob !== 'undefined' && data instanceof Blob) {
return readText(data).then(function(text) {
return loadTableFromCsv(that, text);
});
} else if (typeof data === 'string') {
return loadTableFromCsv(that, data);
} else if (data instanceof TableStructure) {
TableCatalogItem.applyTableStyleColumnsToStructure(that._tableStyle, data);
return that.initializeFromTableStructure(data);
} else {
throw new TerriaError({
sender: that,
title: 'Unexpected type of CSV data',
message: 'CsvCatalogItem data is expected to be a Blob, File, or String, but it was not any of these. ' +
'This may indicate a bug in terriajs or incorrect use of the terriajs API. ' +
'If you believe it is a bug in ' + that.terria.appName + ', please report it by emailing ' +
'<a href="mailto:' + that.terria.supportEmail + '">' + that.terria.supportEmail + '</a>.'
});
}
});
} else if (defined(that.url)) {
var overrideMimeType;
if (defined(that.charSet)) {
overrideMimeType = 'text/csv; charset=' + that.charSet;
}
return loadTextWithMime(proxyCatalogItemUrl(that, that.url, '1d'), undefined, overrideMimeType).then(function(text) {
return loadTableFromCsv(that, text);
}).otherwise(function(e) {
throw new TerriaError({
sender: that,
title: 'Unable to load CSV file',
message: 'See the <a href="https://github.com/TerriaJS/nationalmap/wiki/csv-geo-au">csv-geo-au</a> specification for supported CSV formats.\n\n' + (e.message || e.response)
});
});
}
};
/**
* The same as terriajs-cesium/Source/Core/loadText, but with the ability to pass overrideMimeType through to loadWithXhr.
* @private
*/
function loadTextWithMime(url, headers, overrideMimeType) {
return Resource.fetch({
url : url,
headers : headers,
overrideMimeType: overrideMimeType
});
}
module.exports = CsvCatalogItem;