'use strict';
const shared = require('./shared.js')();
const basicFC = require('./basicFC.js')();
/**
* @class AttribFC
*/
class AttribFC extends basicFC.BasicFC {
// attribute-specific variant for feature class object.
// deals with stuff specific to a feature class that has attributes
/**
* Create an attribute specific feature class object
* @param {Object} parent the Record object that this Feature Class belongs to
* @param {String} idx the service index of this Feature Class. an integer in string format. use '0' for non-indexed sources.
* @param {Object} layerPackage a layer package object from the attribute module for this feature class
* @param {Object} config the config object for this sublayer
*/
constructor (parent, idx, layerPackage, config) {
super(parent, idx, config);
this._layerPackage = layerPackage;
this._geometryType = undefined; // this indicates unknown to the ui.
this._fcount = undefined;
this._quickCache = {};
}
/**
* Returns attribute data for this FC.
*
* @function getAttribs
* @returns {Promise} resolves with a layer attribute data object
*/
getAttribs () {
return this._layerPackage.getAttribs();
}
/**
* Returns layer-specific data for this FC.
*
* @function getLayerData
* @returns {Promise} resolves with a layer data object
*/
getLayerData () {
return this._layerPackage.layerData;
}
// this will actively download / refresh the internal symbology
loadSymbology () {
return this.getLayerData().then(lData => {
if (lData.layerType === 'Feature Layer') {
// feature always has a single item, so index 0
this.symbology = shared.makeSymbologyArray(lData.legend.layers[0].legend);
} else {
// non-feature source. use legend server
return super.loadSymbology();
}
});
}
/**
* 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) {
// TODO revisit the objId parameter. Do we actually need this fallback anymore?
// NOTE: we used to have fallback logic here that would use layer settings
// if this.nameField had no value. Logic has changed to now push
// layer settings to this.nameField during the load event of the
// Record.
if (this.nameField && attribs) {
// extract name
return attribs[this.nameField];
} else {
// FIXME wire in "feature" to translation service
return 'Feature ' + objId;
}
}
/**
* 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 () {
if (this._formattedAttributes) {
return this._formattedAttributes;
}
// TODO after refactor, consider changing this to a warning and just return some dummy value
if (this.layerType === shared.clientLayerType.ESRI_RASTER) {
throw new Error('Attempting to get attributes on a raster layer.');
}
this._formattedAttributes = Promise.all([this.getAttribs(), this.getLayerData()])
.then(([aData, lData]) => {
// create columns array consumable by datables
const columns = lData.fields
.filter(field =>
// assuming there is at least one attribute - empty attribute budnle promises should be rejected, so it never even gets this far
// filter out fields where there is no corresponding attribute data
aData.features[0].attributes.hasOwnProperty(field.name))
.map(field => ({
data: field.name,
title: field.alias || field.name
}));
return {
columns,
rows: aData.features.map(feature => feature.attributes),
fields: lData.fields, // keep fields for reference ...
oidField: lData.oidField, // ... keep a reference to id field ...
oidIndex: aData.oidIndex, // ... and keep id mapping array
renderer: lData.renderer
};
})
.catch(() => {
delete this._formattedAttributes; // delete cached promise when the geoApi `getAttribs` call fails, so it will be requested again next time `getAttributes` is called;
throw new Error('Attrib loading failed');
});
return this._formattedAttributes;
}
/**
* Check to see if the attribute in question is an esriFieldTypeDate type.
*
* @param {String} attribName the attribute name we want to check if it's a date or not
* @return {Promise} resolves to true or false based on the attribName type being esriFieldTypeDate
*/
checkDateType (attribName) {
// TEST STATUS none
// grab attribute info (waiting for it it finish loading)
return this.getLayerData().then(lData => {
// inspect attribute fields
if (lData.fields) {
const attribField = lData.fields.find(field => {
return field.name === attribName;
});
if (attribField && attribField.type) {
return attribField.type === 'esriFieldTypeDate';
}
}
return false;
});
}
/**
* 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) {
// TEST STATUS none
// grab attribute info (waiting for it it finish loading)
return this.getLayerData().then(lData => {
return AttribFC.aliasedFieldNameDirect(attribName, lData.fields);
});
}
static aliasedFieldNameDirect (attribName, fields) {
// TEST STATUS none
let fName = attribName;
// search for aliases
if (fields) {
const attribField = fields.find(field => {
return field.name === attribName;
});
if (attribField && attribField.alias && attribField.alias.length > 0) {
fName = attribField.alias;
}
}
return fName;
}
/**
* Convert an attribute set so that any keys using aliases are converted to proper fields
*
* @param {Object} attribs attribute key-value mapping, potentially with aliases as keys
* @param {Array} fields fields definition array for layer
* @return {Object} attribute key-value mapping with fields as keys
*/
static unAliasAttribs (attribs, fields) {
const newA = {};
fields.forEach(field => {
// attempt to extract on name. if not found, attempt to extract on alias
// dump value into the result
newA[field.name] = attribs.hasOwnProperty(field.name) ? attribs[field.name] : attribs[field.alias];
});
return newA;
}
/**
* Fetches feature information, including geometry, from esri servers for feature layer.
* @param {Integer} objectId for feature to be retrived from the server
* @returns {Promise} promise resolves with an esri Graphic (http://resources.arcgis.com/en/help/arcgis-rest-api/#/Feature_Map_Service_Layer/02r3000000r9000000/)
*/
getServerFeatureInfo (objectId) {
if (this._quickCache[objectId]) {
return Promise.resolve(this._quickCache[objectId]);
}
return new Promise(
(resolve, reject) => {
const parent = this._parent;
const defData = parent._esriRequest({
url: `${parent.rootUrl}/${this._idx}/${objectId}`,
content: {
f: 'json',
},
callbackParamName: 'callback',
handleAs: 'json'
});
defData.then(
serverFeature => {
// server result omits spatial reference
serverFeature.feature.geometry.spatialReference = parent._layer.spatialReference;
this._quickCache[objectId] = serverFeature;
resolve(serverFeature);
}, error => {
console.warn(error);
reject(error);
}
);
});
}
/**
* Fetches a graphic from the given layer.
* Will attempt local copy, will hit the server if not available.
*
* @function fetchGraphic
* @param {Integer} objId ID of object being searched for
* @returns {Promise} resolves with a bundle of information. .graphic is the graphic; .source is where it came from - 'layer' or 'server'; also .layerFC for convenience
*/
fetchGraphic (objId) {
const layerObj = this._parent._layer;
const result = {
graphic: null,
source: null,
layerFC: this
};
// if feature layer, check if graphic is already loaded on the client. return it if found.
if (layerObj.graphics) {
const myG = layerObj.graphics.find(g =>
g.attributes[layerObj.objectIdField] === objId);
if (myG) {
result.graphic = myG;
result.source = 'layer';
return Promise.resolve(result);
}
}
// were not able to get a local copy of the graphic. to the server!
// TODO add some error handling. Cases: failed server call. server call is not a feature
return this.getServerFeatureInfo(objId)
.then(featureInfo => {
result.graphic = featureInfo.feature;
result.source = 'server';
return result;
});
}
}
module.exports = () => ({
AttribFC
});