'use strict';
const layerRecord = require('./layerRecord.js')();
const attribFC = require('./attribFC.js')();
/**
* @class AttribRecord
*/
class AttribRecord extends layerRecord.LayerRecord {
// this class has functions common to layers that have attributes
get clickTolerance () { return this._tolerance; }
/**
* Create a layer record with the appropriate geoApi layer type. Layer config
* should be fully merged with all layer options defined (i.e. this constructor
* will not apply any defaults).
* @param {Object} layerClass the ESRI api object for the layer
* @param {Object} esriRequest the ESRI api object for making web requests with proxy support
* @param {Object} apiRef object pointing to the geoApi. allows us to call other geoApi functions.
* @param {Object} config layer config values
* @param {Object} esriLayer an optional pre-constructed layer
* @param {Function} epsgLookup an optional lookup function for EPSG codes (see geoService for signature)
*/
constructor (layerClass, esriRequest, apiRef, config, esriLayer, epsgLookup) {
super(layerClass, apiRef, config, esriLayer, epsgLookup);
this._esriRequest = esriRequest;
this._tolerance = this.config.tolerance;
}
/**
* Get the best user-friendly name of a field. Uses alias if alias is defined, else uses the system attribute name.
*
* @param {String} attribName the attribute name we want a nice name for
* @return {Promise} resolves to the best available user friendly attribute name
*/
aliasedFieldName (attribName) {
return this._featClasses[this._defaultFC].aliasedFieldName(attribName);
}
/**
* Retrieves attributes from a layer for a specified feature index
* @return {Promise} promise resolving with formatted attributes to be consumed by the datagrid and esri feature identify
*/
getFormattedAttributes () {
return this._featClasses[this._defaultFC].getFormattedAttributes();
}
/**
* Test if an attribute field has a date data type.
*
* @param {String} attribName the attribute name to check if it's a date field
* @return {Promise} resolves with a boolean indicating if attrib name is a date field.
*/
checkDateType (attribName) {
return this._featClasses[this._defaultFC].checkDateType(attribName);
}
/**
* Returns attribute data for this layer.
*
* @function getAttribs
* @returns {Promise} resolves with a layer attribute data object
*/
getAttribs () {
return this._featClasses[this._defaultFC].getAttribs();
}
/**
* Returns layer-specific data for this Record
*
* @function getLayerData
* @returns {Promise} resolves with a layer data object
*/
getLayerData () {
return this._featClasses[this._defaultFC].getLayerData();
}
/**
* Extract the feature name from a feature as best we can.
*
* @function getFeatureName
* @param {String} objId the object id of the attribute
* @param {Object} attribs the dictionary of attributes for the feature.
* @returns {String} the name of the feature
*/
getFeatureName (objId, attribs) {
return this._featClasses[this._defaultFC].getFeatureName(objId, attribs);
}
/**
* Fetches a graphic for the given object id.
* Will attempt local copy (unless overridden), will hit the server if not available.
*
* @function fetchGraphic
* @param {Integer} objId ID of object being searched for
* @param {Object} opts object containing option parametrs
* - map map wrapper object of current map. only required if requesting geometry
* - geom boolean. indicates if return value should have geometry included. default to false
* - attribs boolean. indicates if return value should have attributes included. default to false
* @returns {Promise} resolves with a bundle of information. .graphic is the graphic; .layerFC for convenience
*/
fetchGraphic (objId, opts) {
return this._featClasses[this._defaultFC].fetchGraphic(objId, opts);
}
/**
* Will attempt to zoom the map view so the a graphic is prominent.
*
* @function zoomToGraphic
* @param {Integer} objId Object ID of grahpic being searched for
* @param {Object} map wrapper object for the map we want to zoom
* @param {Object} offsetFraction an object with decimal properties `x` and `y` indicating percentage of offsetting on each axis
* @return {Promise} resolves after the map is done moving
*/
zoomToGraphic (objId, map, offsetFraction) {
return this._featClasses[this._defaultFC].zoomToGraphic(objId, map, offsetFraction);
}
/**
* Get feature count of a feature layer.
*
* @function getFeatureCount
* @param {String} url server url of the feature layer. empty string for file based layers
* @return {Promise} resolves with an integer indicating the feature count. -1 if error occured.
*/
getFeatureCount (url) {
if (url) {
// wrapping server call in a function, as we regularly encounter sillyness
// where we need to execute the count request twice.
// having a function (with finalTry flag) lets us handle the double-request
const esriServerCount = (layerUrl, finalTry = false) => {
// extract info for this service
const defService = this._esriRequest({
url: `${layerUrl}/query`,
content: {
f: 'json',
where: '1=1',
returnCountOnly: true,
returnGeometry: false
},
callbackParamName: 'callback',
handleAs: 'json',
});
return new Promise(resolve => {
defService.then(serviceResult => {
if (serviceResult && (typeof serviceResult.error === 'undefined') &&
(typeof serviceResult.count !== 'undefined')) {
// we got a row count
resolve(serviceResult.count);
} else if (!finalTry) {
// do a second attempt
resolve(esriServerCount(layerUrl, true));
} else {
// tells the app it failed
resolve(-1);
}
}, error => {
// failed to load service info.
// TODO any tricks to avoid duplicating the error case in both blocks?
if (!finalTry) {
// do a second attempt
resolve(esriServerCount(layerUrl, true));
} else {
// tells the app it failed
console.warn(error);
resolve(-1);
}
});
});
};
return esriServerCount(url);
} else {
// file based layer. count local features
return Promise.resolve(this._layer.graphics.length);
}
}
/**
* Transforms esri key-value attribute object into key value array with format suitable
* for consumption by the details pane.
*
* @param {Object} attribs attribute key-value mapping, potentially with aliases as keys
* @param {Array} fields optional. fields definition array for layer. no aliasing done if not provided
* @return {Array} attribute data transformed into a list, with potential field aliasing applied
*/
attributesToDetails (attribs, fields) {
// TODO make this extensible / modifiable / configurable to allow different details looks for different data
// simple array of text mapping for demonstration purposes. fancy grid formatting later?
// ignore any functions hanging around on the attribute.
return Object.keys(attribs)
.filter(key => typeof attribs[key] !== 'function')
.map(key => {
const fieldType = fields ? fields.find(f => f.name === key) : null;
return {
key: attribFC.AttribFC.aliasedFieldNameDirect(key, fields), // need synchronous variant of alias lookup
value: attribs[key],
field: key,
type: fieldType ? fieldType.type : fieldType
};
});
}
}
module.exports = () => ({
AttribRecord
});