'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._oidField = undefined;
this._fcount = undefined;
this._quickCache = {
attribs: {},
geoms: {}
};
}
get geomType () { return this._geometryType; }
set geomType (value) { this._geometryType = value; }
get oidField () { return this._oidField; }
set oidField (value) { this._oidField = value; }
get queryUrl () { return `${this._parent.rootUrl}/${this._idx}`; }
get loadedFeatureCount () { return this._layerPackage ? this._layerPackage.loadedFeatureCount : 0; }
/**
* Returns attribute data for this FC.
*
* @function getAttribs
* @returns {Promise} resolves with a layer attribute data object
*/
getAttribs () {
const attribsDownloaded = this.attribsLoaded();
const attribPromise = this._layerPackage.getAttribs();
attribPromise.then(attrib => {
// only trigger the event the first time when the download was in progress.
// after the attribs have been downloaded, if triggered again through API, since the attributes have
// previously been downloaded, this event will not trigger in the viewer
if (!attribsDownloaded) {
this._parent._attribsAdded(this._idx, attrib.features);
// for file layers, since attributes are local and we have promise initially,
// must set loadIsDone to true after promise resolved to ensure we trigger event once and only once
if (this._parent.isFileLayer()) {
this._layerPackage.loadIsDone = true;
}
}
});
return attribPromise;
}
/**
* Indicates if attributes have been downloaded for this FC.
*
* @function attribsLoaded
* @returns {Boolean} true if attributes are downloaded.
*/
attribsLoaded () {
return this._layerPackage.loadIsDone;
}
/**
* Returns layer-specific data for this FC.
*
* @function getLayerData
* @returns {Promise} resolves with a layer data object
*/
getLayerData () {
return this._layerPackage.layerData;
}
/**
* Attempts to abort an attribute load in progress.
* Harmless to call before or after an attribute load.
*
* @function abortAttribLoad
*/
abortAttribLoad () {
this._layerPackage.abortAttribLoad();
}
/**
* Download or refresh the internal symbology for the FC.
*
* @function loadSymbology
* @returns {Promise} resolves when symbology has been downloaded
*/
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
}));
// derive the icon for the row
const rows = aData.features.map(feature => {
const att = feature.attributes;
att.rvInteractive = '';
att.rvSymbol = this._parent._apiRef.symbology.getGraphicIcon(att, lData.renderer);
return att;
});
// if a field name resembles a function, the data table will treat it as one.
// to get around this, we add a function with the same name that returns the value,
// tricking that silly datagrid.
columns.forEach(c => {
if (c.data.substr(-2) === '()') {
// have to use function() to get .this to reference the row.
// arrow notation will reference the attribFC class.
const secretFunc = function() {
return this[c.data];
};
const stub = c.data.substr(0, c.data.length - 2); // function without brackets
rows.forEach(r => {
r[stub] = secretFunc;
});
}
});
return {
columns,
rows,
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(e => {
delete this._formattedAttributes; // delete cached promise when the geoApi `getAttribs` call fails, so it will be requested again next time `getAttributes` is called;
if (e === 'ABORTED') {
throw new Error('ABORTED');
} else {
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) {
// grab attribute info (waiting for it it finish loading)
return this.getLayerData().then(lData => {
return AttribFC.aliasedFieldNameDirect(attribName, lData.fields);
});
}
/**
* 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
* @param {Array} fields list of field definition objects (esri format) for the layer.
* @return {String} the best available user friendly attribute name
*/
static aliasedFieldNameDirect (attribName, fields) {
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 a graphic from the given layer.
* Will attempt local copy (unless overridden), will hit the server if not available.
*
* @function fetchGraphic
* @param {Integer} objectId 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 (objectId, opts) {
// see https://github.com/fgpv-vpgf/fgpv-vpgf/issues/2190 for reasons why
// things are done the way they are in this function.
// TODO this is currently a mess of IF statements, and a very dirty hack using a promise.
// could certainly use a refactor LATER.
// this function should win a prize for good structure :trophy:
const layerObj = this._parent._layer;
const result = {
graphic: null,
layerFC: this
};
const resultFeat = {};
const nonPoint = this.geomType !== 'esriGeometryPoint';
let needWebAttr = false;
let needWebGeom = false;
let lod;
let gCache;
let aCache;
let localGraphic;
// basically this hack promise handles one odd case where we are getting attributes from
// an asynch source that is very inconvenient (code would be mint if it was synch source).
// so in all other cases, the promse just resolves. in the odd case, it waits, then updates
// the result variable, then resolves.
// so at both points in the code where the main return value promise resolves, we first
// wait on this (which usually resolves right away, and the odd case the thing it's waiting
// on is already resolved, but need to treat it like a promise because of rules!)
let attribHackPromise = Promise.resolve();
// subfunction to extract a graphic from a feature layerk
const huntLocalGraphic = objId => {
return layerObj.graphics.find(g =>
g.attributes[layerObj.objectIdField] === objId);
};
if (opts.attribs) {
// attempt to get attributes from fastest source.
aCache = this._quickCache.attribs;
if (aCache[objectId]) {
// value is already cached. use it
resultFeat.attributes = aCache[objectId];
} else if (this._layerPackage.loadIsDone) {
// all attributes have been loaded. use that store.
// since our store is a promise, need to do some hack trickery here
attribHackPromise = new Promise(resolve => {
this._layerPackage.getAttribs().then(ad => {
resultFeat.attributes = ad.features[ad.oidIndex[objectId]].attributes;
resolve();
});
});
} else if (this._parent.isFileLayer() && layerObj.graphics) {
// it is a feature layer that is file based. we can extract info from it.
localGraphic = huntLocalGraphic(objectId);
resultFeat.attributes = localGraphic.attributes;
} else {
// we will need to ask the service
needWebAttr = true;
}
}
if (opts.geom) {
// first locate the appropriate cache due to simplifications.
gCache = this._quickCache.geoms;
if (nonPoint) {
// lines and polys have a cache for each LOD
const mapLevel = opts.map.getLevel();
lod = opts.map.lods.find(l => l.level === mapLevel);
if (!gCache[lod.scale]) {
gCache[lod.scale] = {};
}
gCache = gCache[lod.scale];
}
// attempt to get geometry from fastest source.
if (gCache[objectId]) {
resultFeat.geometry = gCache[objectId];
} else if (layerObj.graphics) {
// it is a feature layer. we can attempt to extract info from it.
// but remember the feature may not exist on the client currently
if (!localGraphic) {
// wasn't fetched during attribute section. do it now
localGraphic = huntLocalGraphic(objectId);
}
if (localGraphic) {
// found one. cache it and use it
gCache[objectId] = localGraphic.geometry;
resultFeat.geometry = localGraphic.geometry;
} else {
needWebGeom = true;
}
} else {
needWebGeom = true;
}
}
// hit the server if we dont have cached values
if (needWebAttr || needWebGeom) {
return new Promise(
(resolve, reject) => {
const parent = this._parent;
const reqParam = {
url: `${parent.rootUrl}/${this._idx}/query`,
content: {
f: 'json',
objectIds: objectId,
outFields: '*',
returnGeometry: needWebGeom
},
callbackParamName: 'callback',
handleAs: 'json'
};
if (needWebGeom) {
reqParam.content.outSR = map.spatialReference;
if (nonPoint) {
reqParam.content.maxAllowableOffset = lod.resolution;
}
}
// TODO investigate adding `geometryPrecision` to the param.
// if we have bloated decimal places, this will drop them.
// need to be careful of the units of the map and the current scale.
// e.g. a basemap in lat long will certainly need decimal places.
const defData = parent._esriRequest(reqParam);
defData.then(
queryResult => {
const feat = queryResult.features[0];
if (!feat) {
throw new Error(`Could not find feature (oid ${objectId})`);
}
if (needWebGeom) {
// server result omits spatial reference
feat.geometry.spatialReference = queryResult.spatialReference;
gCache[objectId] = feat.geometry;
resultFeat.geometry = feat.geometry;
}
if (needWebAttr) {
aCache[objectId] = feat.attributes;
resultFeat.attributes = feat.attributes;
}
result.graphic = resultFeat;
attribHackPromise.then(() => {
resolve(result);
});
}, error => {
console.warn(error);
reject(error);
}
);
});
} else {
// no need for web requests. everything was available locally
return attribHackPromise.then(() => {
result.graphic = resultFeat;
return result;
});
}
}
/**
* 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.fetchGraphic(objId, { map, geom: true })
.then(fetchedGraphic => {
const gapi = this._parent._apiRef;
// make new graphic (on the chance it came from server and is just raw json geometry)
const graphic = gapi.proj.Graphic(fetchedGraphic.graphic);
// reproject graphic to spatialReference of the map
let extent = gapi.proj.graphicsUtils.graphicsExtent([graphic]);
if (!gapi.proj.isSpatialRefEqual(graphic.geometry.spatialReference, map.spatialReference)) {
const intermExtent = gapi.proj.localProjectExtent(extent, map.spatialReference);
extent = gapi.Map.Extent(intermExtent.x0, intermExtent.y0,
intermExtent.x1, intermExtent.y1, intermExtent.sr);
}
// move map according to geometry
let geomZoomPromise;
if (this.geomType === 'esriGeometryPoint') {
// zoom to point at a decent scale for hilighting a point
const sweetLod = gapi.Map.findClosestLOD(map.lods, 50000);
geomZoomPromise = map.centerAndZoom(extent.getCenter(), Math.max(sweetLod.level, 0));
} else {
// zoom to the extent of the geometery
geomZoomPromise = map.setExtent(extent, true);
}
// make next step wait for map to zoom, and pass it our projected target extent.
return geomZoomPromise.then(() => extent);
}).then(extent => {
// determine if our optimal zoom is offscale
const scale = this.isOffScale(map.getScale());
// adjust the scale if the layer is offscale
const scaleZoomPromise = scale.offScale ?
this.zoomToScale(map, map.lods, scale.zoomIn, false) : Promise.resolve();
return scaleZoomPromise.then(() => extent);
}).then(extent => {
// map is at best position we can manage. do any offsetting for UI elements
return map.moveToOffsetExtent(extent, offsetFraction);
});
}
}
module.exports = () => ({
AttribFC
});