'use strict';
// TODO consider splitting this module into different modules. in particular,
// file-based stuff vs server based stuff, and layer creation vs layer support
// TODO convert internal function header comments to JSDoc, and use the @private tag
const csv2geojson = require('csv2geojson');
const Terraformer = require('terraformer');
const shp = require('shpjs');
const ogc = require('./layer/ogc.js');
const bbox = require('./layer/bbox.js');
const layerRecord = require('./layer/layerRec/main.js');
const defaultRenderers = require('./defaultRenderers.json');
Terraformer.ArcGIS = require('terraformer-arcgis-parser');
/**
* Maps GeoJSON geometry types to a set of default renders defined in GlobalStorage.DefaultRenders
* @property featureTypeToRenderer {Object}
* @private
*/
const featureTypeToRenderer = {
Point: 'circlePoint',
MultiPoint: 'circlePoint',
LineString: 'solidLine',
MultiLineString: 'solidLine',
Polygon: 'outlinedPoly',
MultiPolygon: 'outlinedPoly'
};
/**
* Different types of services that a URL could point to
* @property serviceType {Object}
*/
const serviceType = {
CSV: 'csv',
GeoJSON: 'geojson',
Shapefile: 'shapefile',
FeatureLayer: 'featurelayer',
RasterLayer: 'rasterlayer',
GroupLayer: 'grouplayer',
TileService: 'tileservice',
FeatureService: 'featureservice',
DynamicService: 'dynamicservice',
ImageService: 'imageservice',
WMS: 'wms',
Unknown: 'unknown',
Error: 'error'
};
// returns a standard information object with serviceType
// supports predictLayerUrl
// type is serviceType enum value
function makeInfo(type) {
return {
serviceType: type,
index: -1,
tileSupport: false
};
}
/**
* Returns a standard information object with info common for most ESRI endpoints
* .serviceName
* .serviceType
* .tileSupport
* .rootUrl
*
* @function makeLayerInfo
* @private
* @param {String} type serviceType enum value for layer
* @param {String} name property in json parameter containing a service name
* @param {String} url url we are investigating
* @param {Object} json data result from service we interrogated
* @returns {Object}
*/
function makeLayerInfo(type, name, url, json) {
const info = makeInfo(type);
info.serviceName = json[name] || '';
info.rootUrl = url;
if (type === serviceType.TileService) {
info.tileSupport = true;
info.serviceType = serviceType.DynamicService;
}
return info;
}
// inspects the JSON that was returned from a service.
// if the JSON belongs to an ESRI endpoint, we do some terrible dog-logic to attempt
// to derive what type of endpoint it is (mainly by looking for properties that are
// unique to that type of service).
// returns an enumeration value (string) from serviceType based on the match found.
// non-esri services or unexpected esri services will return the .Unknown value
function crawlEsriService(srvJson) {
if (srvJson.type) {
// a layer endpoint (i.e. url ends with integer index)
const mapper = {
'Feature Layer': serviceType.FeatureLayer,
'Raster Layer': serviceType.RasterLayer,
'Group Layer': serviceType.GroupLayer
};
return mapper[srvJson.type] || serviceType.Unknown;
} else if (srvJson.hasOwnProperty('singleFusedMapCache')) {
if (srvJson.singleFusedMapCache) {
// a tile server
return serviceType.TileService;
} else {
// a map server
return serviceType.DynamicService;
}
} else if (srvJson.hasOwnProperty('allowGeometryUpdates')) {
// a feature server
return serviceType.FeatureService;
} else if (srvJson.hasOwnProperty('allowedMosaicMethods')) {
// an image server
return serviceType.ImageService;
} else {
return serviceType.Unknown;
}
}
/**
* handles the situation where our first poke revealed a child layer
* (i.e. an indexed endpoint in an arcgis server). We need to extract
* some extra information about the service it resides in (the root service)
* and add it to our info package.
*
* @param {String} url the url of the original endpoint (including the index)
* @param {Object} esriBundle has ESRI API objects
* @param {Object} childInfo the information we have gathered on the child layer from the first poke
* @returns {Promise} resolves with information object containing child and root information
*/
function repokeEsriService(url, esriBundle, childInfo) {
// break url into root and index
const re = /\/(\d+)\/?$/;
const matches = url.match(re);
if (!matches) {
// give up, dont crash with error.
console.warn('Cannot extract layer index from url ' + url);
return Promise.resolve(childInfo);
}
childInfo.index = parseInt(matches[1]);
childInfo.rootUrl = url.substr(0, url.length - matches[0].length); // will drop trailing slash
// inspect the server root
return pokeEsriService(childInfo.rootUrl, esriBundle).then(rootInfo => {
// take relevant info from root, mash it into our child package
childInfo.tileSupport = rootInfo.tileSupport;
childInfo.serviceType = rootInfo.serviceType;
childInfo.layers = rootInfo.layers;
return childInfo;
});
}
// given a URL, attempt to read it as an ESRI rest endpoint.
// returns a promise that resovles with an information object.
// at minimum, the object will have a .serviceType property with a value from the above enumeration.
// if the type is .Unknown, then we were unable to determine the url was an ESRI rest endpoint.
// otherwise, we were successful, and the information object will have other properties depending on the service type
// - .name : scraped from service, but may be rubbish (depends on service publisher). used as UI suggestion only
// - .fields : for feature layer service only. list of fields to allow user to pick name field
// - .geometryType : for feature layer service only. for help in defining the renderer, if required.
// - .layers : for dynamic layer service only. lists the child layers
function pokeEsriService(url, esriBundle, hint) {
// reaction functions to different esri services
const srvHandler = {};
srvHandler[serviceType.FeatureLayer] = srvJson => {
const info = makeLayerInfo(serviceType.FeatureLayer, 'name', url, srvJson);
info.fields = srvJson.fields;
info.geometryType = srvJson.geometryType;
info.smartDefaults = {
// TODO: try to find a name field if possible
primary: info.fields[0].name // pick the first field as primary and return its name for ui binding
};
info.indexType = serviceType.FeatureLayer;
return repokeEsriService(url, esriBundle, info);
};
srvHandler[serviceType.RasterLayer] = srvJson => {
const info = makeLayerInfo(serviceType.RasterLayer, 'name', url, srvJson);
info.indexType = serviceType.RasterLayer;
return repokeEsriService(url, esriBundle, info);
};
srvHandler[serviceType.GroupLayer] = srvJson => {
const info = makeLayerInfo(serviceType.GroupLayer, 'name', url, srvJson);
info.indexType = serviceType.GroupLayer;
return repokeEsriService(url, esriBundle, info);
};
srvHandler[serviceType.TileService] = srvJson => {
const info = makeLayerInfo(serviceType.TileService, 'mapName', url, srvJson);
info.layers = srvJson.layers;
return info;
};
srvHandler[serviceType.DynamicService] = srvJson => {
const info = makeLayerInfo(serviceType.DynamicService, 'mapName', url, srvJson);
info.layers = srvJson.layers;
return info;
};
srvHandler[serviceType.FeatureService] = srvJson => {
const info = makeLayerInfo(serviceType.FeatureService, 'description', url, srvJson);
info.layers = srvJson.layers;
return info;
};
srvHandler[serviceType.ImageService] = srvJson => {
const info = makeLayerInfo(serviceType.ImageService, 'name', url, srvJson);
info.fields = srvJson.fields;
return info;
};
// couldnt figure it out
srvHandler[serviceType.Unknown] = () => {
return makeInfo(serviceType.Unknown);
};
return new Promise(resolve => {
// extract info for this service
const defService = esriBundle.esriRequest({
url: url,
content: { f: 'json' },
callbackParamName: 'callback',
handleAs: 'json',
});
defService.then(srvResult => {
// request didnt fail, indicating it is likely an ArcGIS Server endpoint
let resultType = crawlEsriService(srvResult);
if (hint && resultType !== hint) {
// our hint doesn't match the service
resultType = serviceType.Unknown;
}
resolve(srvHandler[resultType](srvResult));
}, () => {
// something went wrong, but that doesnt mean our service is invalid yet
// it's likely not ESRI. return Error and let main predictor keep investigating
resolve(makeInfo(serviceType.Error));
});
});
}
// tests a URL to see if the value is a file
// providing the known type as a hint will cause the function to run the
// specific logic for that file type, rather than guessing and trying everything
// resolves with promise of information object
// - serviceType : the type of file (CSV, Shape, GeoJSON, Unknown)
// - fileData : if the file is located on a server, will xhr
function pokeFile(url, hint) {
// reaction functions to different files
// overkill right now, as files just identify the type right now
// but structure will let us enhance for custom things if we need to
const fileHandler = {};
// csv
fileHandler[serviceType.CSV] = () => {
return makeInfo(serviceType.CSV);
};
// geojson
fileHandler[serviceType.GeoJSON] = () => {
return makeInfo(serviceType.GeoJSON);
};
// csv
fileHandler[serviceType.Shapefile] = () => {
return makeInfo(serviceType.Shapefile);
};
// couldnt figure it out
fileHandler[serviceType.Unknown] = () => {
// dont supply url, as we don't want to download random files
return makeInfo(serviceType.Unknown);
};
return new Promise(resolve => {
if (hint) {
// force the data extraction of the hinted format
resolve(fileHandler[hint]());
} else {
// inspect the url for file extensions
let guessType = serviceType.Unknown;
switch (url.substr(url.lastIndexOf('.') + 1).toLowerCase()) {
// check for file extensions
case 'csv':
guessType = serviceType.CSV;
break;
case 'zip':
guessType = serviceType.Shapefile;
break;
case 'json':
guessType = serviceType.GeoJSON;
break;
}
resolve(fileHandler[guessType]());
}
});
}
// tests a URL to see if the value is a wms
// resolves with promise of information object
// - serviceType : the type of service (WMS, Unknown)
function pokeWms(url, esriBundle) {
// FIXME add some WMS detection logic. that would be nice
console.log(url, esriBundle); // to stop jslint from quacking. remove when params are actually used
return Promise.resolve(makeInfo(serviceType.WMS));
}
function predictLayerUrlBuilder(esriBundle) {
/**
* Attempts to determine what kind of layer the URL most likely is, and
* if possible, return back some useful information about the layer
*
* - serviceType: the type of layer the function thinks the url is referring to. is a value of serviceType enumeration (string)
* - fileData: file contents in an array buffer. only present if the URL points to a file that exists on an internet server (i.e. not a local disk drive)
* - name: best attempt at guessing the name of the service (string). only present for ESRI service URLs
* - fields: array of field definitions for the layer. conforms to ESRI's REST field standard. only present for feature layer and image service URLs.
* - geometryType: describes the geometry of the layer (string). conforms to ESRI's REST geometry type enum values. only present for feature layer URLs.
* - groupIdx: property only available if a group layer is queried. it is the layer index of the group layer in the list under its parent dynamic layer
*
* @method predictLayerUrl
* @param {String} url a url to something that is hopefully a map service
* @param {String} hint optional. allows the caller to specify the url type, forcing the function to run the data logic for that type
* @returns {Promise} a promise resolving with an infomation object
*/
return (url, hint) => {
// TODO this function has lots of room to improve. there are many valid urls that it will
// fail to identify correctly in it's current state
// TODO refactor how this function works.
// wait for the web service request library to not be esri/request
// use new library to make a head call on the url provided
// examine the content type of the head call result
// if xml, assume WMS
// if json, assume esri (may need extra logic to differentiate from json file?)
// file case is explicit (e.g text/json)
// then hit appropriate handler, do a second web request for content if required
if (hint) {
// go directly to appropriate logic block
const hintToFlavour = {}; // why? cuz cyclomatic complexity + OBEY RULES
const flavourToHandler = {};
// hint type to hint flavour
hintToFlavour[serviceType.CSV] = 'F_FILE';
hintToFlavour[serviceType.GeoJSON] = 'F_FILE';
hintToFlavour[serviceType.Shapefile] = 'F_FILE';
hintToFlavour[serviceType.FeatureLayer] = 'F_ESRI';
hintToFlavour[serviceType.RasterLayer] = 'F_ESRI';
hintToFlavour[serviceType.GroupLayer] = 'F_ESRI';
hintToFlavour[serviceType.TileService] = 'F_ESRI';
hintToFlavour[serviceType.DynamicService] = 'F_ESRI';
hintToFlavour[serviceType.ImageService] = 'F_ESRI';
hintToFlavour[serviceType.WMS] = 'F_WMS';
// hint flavour to flavour-handler
flavourToHandler.F_FILE = () => {
return pokeFile(url, hint);
};
flavourToHandler.F_ESRI = () => {
return pokeEsriService(url, esriBundle, hint);
};
flavourToHandler.F_WMS = () => {
// FIXME REAL LOGIC COMING SOON
return pokeWms(url, esriBundle);
};
// execute handler. hint -> flavour -> handler -> run it -> promise
return flavourToHandler[hintToFlavour[hint]]();
} else {
// TODO restructure. this approach cleans up the pyramid of doom.
// Needs to add check for empty tests, resolve as unknown.
// Still a potential to take advantage of the nice structure. Will depend
// what comes first: WMS logic (adding a 3rd test), or changing the request
// library, meaning we get the type early from the head request.
/*
tests = [pokeFile, pokeService];
function runTests() {
test = tests.pop();
test(url, esriBundle).then(info => {
if (info.serviceType !== serviceType.Unknown) {
resolve(info);
return;
}
runTests();
});
}
runTests();
*/
return new Promise(resolve => {
// no hint. run tests until we find a match.
// test for file
pokeFile(url).then(infoFile => {
if (infoFile.serviceType === serviceType.Unknown ||
infoFile.serviceType === serviceType.Error) {
// not a file, test for ESRI
pokeEsriService(url, esriBundle).then(infoEsri => {
if (infoEsri.serviceType === serviceType.Unknown ||
infoEsri.serviceType === serviceType.Error) {
// FIXME REAL LOGIC COMING SOON
// pokeWMS
resolve(infoEsri);
} else {
// it was a esri service. rejoice.
// shortlived rejoice because grouped layers lul
if (infoEsri.serviceType === serviceType.GroupLayer) {
const lastSlash = url.lastIndexOf('/');
const layerIdx = parseInt(url.substring(lastSlash + 1));
url = url.substring(0, lastSlash);
pokeEsriService(url, esriBundle).then(infoDynamic => {
infoDynamic.groupIdx = layerIdx;
resolve(infoDynamic);
});
} else {
resolve(infoEsri);
}
}
});
} else {
// it was a file. rejoice.
resolve(infoFile);
}
});
});
}
};
}
/**
* Converts an array buffer to a string
*
* @method arrayBufferToString
* @private
* @param {Arraybuffer} buffer an array buffer containing stuff (ideally string-friendly)
* @returns {String} array buffer in string form
*/
function arrayBufferToString(buffer) {
// handles UTF8 encoding
return new TextDecoder('utf-8').decode(new Uint8Array(buffer));
}
/**
* Performs validation on GeoJson object. Returns a promise resolving with the validation object.
* Worker function for validateFile, see that file for return value specs
*
* @method validateGeoJson
* @private
* @param {Object} geoJson feature collection in geojson form
* @returns {Promise} promise resolving with information on the geoJson object
*/
function validateGeoJson(geoJson) {
// GeoJSON geometry type to ESRI geometry type
const geomMap = {
Point: 'esriGeometryPoint',
MultiPoint: 'esriGeometryMultipoint',
LineString: 'esriGeometryPolyline',
MultiLineString: 'esriGeometryPolyline',
Polygon: 'esriGeometryPolygon',
MultiPolygon: 'esriGeometryPolygon'
};
const fields = extractFields(geoJson);
const oid = 'OBJECTID';
// object id will be added by the loader later, so present it as an option for the user to pick
if (fields.indexOf(f => f.name === oid) === -1) {
fields.push({ name: oid, type: 'esriFieldTypeString' });
}
const res = {
fields: fields,
geometryType: geomMap[geoJson.features[0].geometry.type],
formattedData: geoJson,
smartDefaults: {
// TODO: try to find a name field if possible
primary: fields[0].name // pick the first field as primary and return its name for ui binding
}
};
if (!res.geometryType) {
return Promise.reject(new Error('Unexpected geometry type in GeoJSON'));
}
// TODO optional check: iterate through every feature, ensure geometry type and properties are all identical
return Promise.resolve(res);
}
/**
* Performs validation on csv data. Returns a promise resolving with the validation object.
* Worker function for validateFile, see that file for return value specs
*
* @method validateCSV
* @private
* @param {Object} data csv data as string
* @returns {Promise} promise resolving with information on the csv data
*/
function validateCSV(data) {
const formattedData = arrayBufferToString(data); // convert from arraybuffer to string to parsed csv. store string format for later
const rows = csvPeek(formattedData, ','); // FIXME: this assumes delimiter is a `,`; need validation
let errorMessage; // error message if any to return
// validations
if (rows.length < 2) {
// fail, not enough rows
errorMessage = 'File does not have enough rows';
} else {
// field count of first row.
const fc = rows[0].length;
if (fc < 2) {
// fail not enough columns
errorMessage = 'File has less than two columns';
} else {
// check field counts of each row
if (rows.every(rowArr => rowArr.length === fc)) {
// regex values
const latValueRegex = new RegExp(/^(\+|-)?(?:90(?:(?:\.0{1,6})?)|(?:[0-9]|[1-8][0-9])(?:(?:\.[0-9]{1,6})?))$/);
const longValueRegex = new RegExp(/^(\+|-)?(?:180(?:(?:\.0{1,6})?)|(?:[0-9]|[1-9][0-9]|1[0-7][0-9])(?:(?:\.[0-9]{1,6})?))$/);
// candidate fields for latitude and longitude
const latCandidates = findCandidates(rows, latValueRegex);
const longCandidates = findCandidates(rows, longValueRegex);
// reject if no latitude or longitude candidates were found
if (latCandidates.length === 0 || longCandidates.length === 0) {
return Promise.reject(new Error('Invalid csv format'));
}
const res = {
formattedData,
// default display fields
smartDefaults: guessCSVfields(rows, latCandidates, longCandidates),
// candidate fields for latitude and longitude wrapped in an object with an esri type
latFields: latCandidates.map(field => ({
name: field,
type: 'esriFieldTypeString'
})),
longFields: longCandidates.map(field => ({
name: field,
type: 'esriFieldTypeString'
})),
// make field list esri-ish for consistancy
fields: rows[0].map(field => ({
name: field,
type: 'esriFieldTypeString'
})),
geometryType: 'esriGeometryPoint' // always point for CSV
};
return Promise.resolve(res);
} else {
errorMessage = 'File has inconsistent column counts';
}
}
}
return Promise.reject(new Error(errorMessage));
}
/**
* Validates file content. Does some basic checking for errors. Attempts to get field list, and
* if possible, provide the file in a more useful format. Promise rejection indicates failed validation
*
* - formattedData: file contents in a more useful format. JSON for GeoJSON and Shapefile. String for CSV
* - fields: array of field definitions for the file. conforms to ESRI's REST field standard.
* - geometryType: describes the geometry of the file (string). conforms to ESRI's REST geometry type enum values.
*
* @method validateFile
* @param {String} type the format of file. aligns to serviceType enum (CSV, Shapefile, GeoJSON)
* @param {Arraybuffer} data the file content in binary
* @returns {Promise} a promise resolving with an infomation object
*/
function validateFile(type, data) {
const fileHandler = { // maps handlers for different file types
[serviceType.CSV]: data => validateCSV(data),
[serviceType.GeoJSON]: data => {
const geoJson = JSON.parse(arrayBufferToString(data));
return validateGeoJson(geoJson);
},
// convert from arraybuffer (containing zipped shapefile) to json (using shp library)
[serviceType.Shapefile]: data =>
shp(data).then(geoJson =>
validateGeoJson(geoJson))
};
// trigger off the appropriate handler, return promise
return fileHandler[type](data);
}
/**
* From provided CSV data, guesses which columns are long and lat with in the canadidates.
* If guessing is no successful, returns null for one or both fields.
*
* @method guessCSVfields
* @private
* @param {Array} rows csv data
* @param {Array} latCandidates list of all the valid latitude fields
* @param {Array} longCandidates list of all the valid longitude fields
* @return {Object} an object with lat and long string properties indicating corresponding field names
*/
function guessCSVfields(rows, latCandidates, longCandidates) {
const latNameRegex = new RegExp(/^.*(y|lat).*$/i);
const longNameRegex = new RegExp(/^.*(x|long).*$/i);
// pick the candidate most likely to be the latitude
let lat = latCandidates[0] || null;
for (let i in latCandidates) {
if (latNameRegex.test(latCandidates[i])) {
lat = latCandidates[i];
break;
}
}
// pick the candidate most likely to be the longitude
let long = longCandidates.find(field => field !== lat) || null;
for (let j in longCandidates) {
if (longNameRegex.test(longCandidates[j]) && longCandidates[j] !== lat) {
long = longCandidates[j];
break;
}
}
// for primary field, pick the first on that is not lat or long field or null
const primary = rows[0].find(field => field !== lat && field !== long) || null;
return {
lat,
long,
primary
};
}
/**
* Find the suitable candidate fields that passes the regular expressions specified
*
* @method findCandidates
* @private
* @param {Array} rows csv data
* @param {RegExp} regular expression for the value of the field
* @return {Array} a list of suitable candidate fields
*/
function findCandidates(rows, valueRegex) {
const fields = rows[0]; // first row must be headers
const candidates =
fields.filter((field, index) =>
rows.every((row, rowIndex) =>
rowIndex === 0 || valueRegex.test(row[index]))); // skip first row as its just headers
return candidates;
}
function serverLayerIdentifyBuilder(esriBundle) {
// TODO we are using layerIds option property as it aligns with what the ESRI identify parameter
// object uses. However, in r2 terminology, a layerId is specific to a full map layer, not
// indexes of a single dynamic layer. for clarity, could consider renaming to .visibleLayers
// and then map the value to the .layerIds property inside this function.
/**
* Perform a server-side identify on a layer (usually an ESRI dynamic layer)
* Accepts the following options:
* - geometry: Required. geometry in map co-ordinates for the area to identify.
* will usually be an ESRI Point, though a polygon would work.
* - mapExtent: Required. ESRI Extent of the current map view
* - width: Required. Width of the map in pixels
* - height: Required. Height of the map in pixels
* - layerIds: an array of integers specifying the layer indexes to be examined. Will override the current
* visible indexes in the layer parameter
* - returnGeometry: a boolean indicating if result geometery should be returned with results. Defaults to false
* - tolerance: an integer indicating how many screen pixels away from the mouse is valid for a hit. Defaults to 5
*
* @method serverLayerIdentify
* @param {Object} layer an ESRI dynamic layer object
* @param {Object} opts An object for supplying additional parameters
* @returns {Promise} a promise resolving with an array of identify results (empty array if no hits)
*/
return (layer, opts) => {
const identParams = new esriBundle.IdentifyParameters();
// pluck treats from options parameter
if (opts) {
const reqOpts = ['geometry', 'mapExtent', 'height', 'width'];
reqOpts.forEach(optProp => {
if (opts[optProp]) {
identParams[optProp] = opts[optProp];
} else {
throw new Error(`serverLayerIdentify - missing opts.${ optProp } arguement`);
}
});
identParams.layerIds = opts.layerIds || layer.visibleLayers;
identParams.returnGeometry = opts.returnGeometry || false;
identParams.layerOption = esriBundle.IdentifyParameters.LAYER_OPTION_ALL;
identParams.spatialReference = opts.geometry.spatialReference;
identParams.tolerance = opts.tolerance || 5;
// TODO add support for identParams.layerDefinitions once attribute filtering is implemented
} else {
throw new Error('serverLayerIdentify - missing opts arguement');
}
// asynch an identify task
return new Promise((resolve, reject) => {
const identify = new esriBundle.IdentifyTask(layer.url);
// TODO possibly tack on the layer.id to the resolved thing so we know which parent layer returned?
// would only be required if the caller is mashing promises together and using Promise.all()
identify.on('complete', result => {
resolve(result.results);
});
identify.on('error', err => {
reject(err.error);
});
identify.execute(identParams);
});
};
}
/**
* Performs in place assignment of integer ids for a GeoJSON FeatureCollection.
* If at least one feature has an existing id outside the geoJson properties section,
* the original id value is copied in a newly created property ID_FILE of the properties object
* and the existing id value is replaced by an autogenerated number.
* Features without existing id from that same dataset will get a new properties ID_FILE
* with an empty string as value.
**************************************
* If at least one feature has an existing OBJECTID inside the geoJson properties section,
* the original OBJECTID value is copied in a newly created property OBJECTID_FILE of the properties object
* and the existing OBJECTID value is replaced by an autogenerated number.
* Features without existing OBJECTID from that same dataset will get a new properties OBJECTID_FILE
* with an empty string as value.
*/
function assignIds(geoJson) {
if (geoJson.type !== 'FeatureCollection') {
throw new Error('Assignment can only be performed on FeatureCollections');
}
let emptyID = true;
let emptyObjID = true;
// for every feature, if it does not have an id property, add it.
// 0 is not a valid object id
geoJson.features.forEach(function (val, idx) {
Object.assign(val.properties, { ID_FILE: '', OBJECTID_FILE: '' });
// to avoid double ID columns outside properties
if ('id' in val && typeof val.id !== 'undefined') {
val.properties.ID_FILE = val.id;
emptyID = false;
}
// to avoid double OBJECTID columns. Useful for both geojson and CSV file.
if ('OBJECTID' in val.properties) {
val.properties.OBJECTID_FILE = val.properties.OBJECTID;
delete val.properties.OBJECTID;
emptyObjID = false;
}
val.id = idx + 1;
});
// remove ID_FILE if all empty
if (emptyID) {
geoJson.features.forEach(function (val) {
delete val.properties.ID_FILE;
});
}
// remove OBJECTID_FILE if all empty
if (emptyObjID) {
geoJson.features.forEach(function (val) {
delete val.properties.OBJECTID_FILE;
});
}
}
/**
* Extracts fields from the first feature in the feature collection, does no
* guesswork on property types and calls everything a string.
*/
function extractFields(geoJson) {
if (geoJson.features.length < 1) {
throw new Error('Field extraction requires at least one feature');
}
if (geoJson.features[0].properties) {
return Object.keys(geoJson.features[0].properties).map(function (prop) {
return { name: prop, type: 'esriFieldTypeString' };
});
} else {
return [];
}
}
/**
* Rename any fields with invalid names. Both parameters are modified in place.
*
* @function cleanUpFields
* @param {Object} geoJson layer data in geoJson format
* @param {Object} layerDefinition layer definition of feature layer not yet created
*/
function cleanUpFields(geoJson, layerDefinition) {
const badField = name => {
// basic for now. check for spaces.
return name.indexOf(' ') > -1;
};
layerDefinition.fields.forEach(f => {
if (badField(f.name)) {
const oldField = f.name;
let newField;
let underscore = '_';
let badNewName;
// determine a new field name that is not bad and is unique, then update the field definition
do {
newField = oldField.replace(/ /g, underscore);
badNewName = layerDefinition.fields.find(f2 => f2.name === newField);
if (badNewName) {
// new field already exists. enhance it
underscore += '_';
}
} while (badNewName)
f.alias = oldField;
f.name = newField;
// update the geoJson to reflect the field name change.
geoJson.features.forEach(gf => {
gf.properties[newField] = gf.properties[oldField];
delete gf.properties[oldField];
});
}
});
}
/**
* Makes an attempt to load and register a projection definition.
* Returns promise resolving when process is complete
* projModule - proj module from geoApi
* projCode - the string or int epsg code we want to lookup
* epsgLookup - function that will do the epsg lookup, taking code and returning promise of result or null
*/
function projectionLookup(projModule, projCode, epsgLookup) {
// look up projection definitions if it's not already loaded and we have enough info
if (!projModule.getProjection(projCode) && epsgLookup && projCode) {
return epsgLookup(projCode).then(projDef => {
if (projDef) {
// register projection
projModule.addProjection(projCode, projDef);
}
return projDef;
});
} else {
return Promise.resolve(null);
}
}
function makeGeoJsonLayerBuilder(esriBundle, geoApi) {
/**
* Converts a GeoJSON object into a FeatureLayer. Expects GeoJSON to be formed as a FeatureCollection
* containing a uniform feature type (FeatureLayer type will be set according to the type of the first
* feature entry). Accepts the following options:
* - targetWkid: Required. an integer for an ESRI wkid to project geometries to
* - renderer: a string identifying one of the properties in defaultRenders
* - sourceProjection: a string matching a proj4.defs projection to be used for the source data (overrides
* geoJson.crs)
* - epsgLookup: a function that takes an EPSG code (string or number) and returns a promise of a proj4 style
* definition or null if not found
* - layerId: a string to use as the layerId
* - colour: a hex string to define the symbol colour. e.g. '#33DD6A'
*
* @method makeGeoJsonLayer
* @param {Object} geoJson An object following the GeoJSON specification, should be a FeatureCollection with
* Features of only one type
* @param {Object} opts An object for supplying additional parameters
* @returns {Promise} a promise resolving with a {FeatureLayer}
*/
return (geoJson, opts) => {
// NOTE we used to have a 'fields' option where a caller could specify a custom field list.
// this was problematic as changes made by assignIds would not be reflected in the
// supplied list. Our UI currently has no way of doing custom lists; it just
// throws every field in, so technically it's not used / not required.
// If we decide we need this, we can add it back, and will need to either
// a) stop the standard file load wizard from passing the .fields option.
// b) write code here that synchs the .fields option with any changes
// made by assignIds
// TODO add documentation on why we only support layers with WKID (and not WKT).
let targetWkid;
let srcProj = 'EPSG:4326'; // 4326 is the default for GeoJSON with no projection defined
let layerId;
const layerDefinition = {
objectIdField: 'OBJECTID',
fields: [
{
name: 'OBJECTID',
type: 'esriFieldTypeOID',
},
],
};
// ensure our features have ids
assignIds(geoJson);
layerDefinition.drawingInfo =
defaultRenderers[featureTypeToRenderer[geoJson.features[0].geometry.type]];
// attempt to get spatial reference from geoJson
if (geoJson.crs && geoJson.crs.type === 'name') {
srcProj = geoJson.crs.properties.name;
}
// pluck treats from options parameter
if (opts) {
if (opts.sourceProjection) {
srcProj = opts.sourceProjection;
}
if (opts.targetWkid) {
targetWkid = opts.targetWkid;
} else {
throw new Error('makeGeoJsonLayer - missing opts.targetWkid arguement');
}
if (opts.layerId) {
layerId = opts.layerId;
} else {
layerId = geoApi.shared.generateUUID();
}
// TODO add support for renderer option, or drop the option
} else {
throw new Error('makeGeoJsonLayer - missing opts arguement');
}
if (layerDefinition.fields.length === 1) {
// caller has not supplied custom field list. so take them all.
layerDefinition.fields = layerDefinition.fields.concat(extractFields(geoJson));
}
// clean the fields. in particular, CSV files can be loaded with spaces in
// the field names
cleanUpFields(geoJson, layerDefinition);
const destProj = 'EPSG:' + targetWkid;
// look up projection definitions if they don't already exist and we have enough info
const srcLookup = projectionLookup(geoApi.proj, srcProj, opts.epsgLookup);
const destLookup = projectionLookup(geoApi.proj, destProj, opts.epsgLookup);
// make the layer
const buildLayer = () => {
return new Promise(resolve => {
// project data and convert to esri json format
// console.log('reprojecting ' + srcProj + ' -> EPSG:' + targetWkid);
geoApi.proj.projectGeojson(geoJson, destProj, srcProj);
const esriJson = Terraformer.ArcGIS.convert(geoJson, { sr: targetWkid });
const geometryType = layerDefinition.drawingInfo.geometryType;
const fs = {
features: esriJson,
geometryType
};
const layer = new esriBundle.FeatureLayer(
{
layerDefinition: layerDefinition,
featureSet: fs
}, {
mode: esriBundle.FeatureLayer.MODE_SNAPSHOT,
id: layerId
});
// ＼(｀O´)／ manually setting SR because it will come out as 4326
layer.spatialReference = new esriBundle.SpatialReference({ wkid: targetWkid });
if (opts.colour) {
layer.renderer.symbol.color = new esriBundle.Color(opts.colour);
}
// initializing layer using JSON does not set this property. do it manually.
layer.geometryType = geometryType;
resolve(layer);
});
};
// call promises in order
return srcLookup
.then(() => destLookup)
.then(() => buildLayer());
};
}
function makeCsvLayerBuilder(esriBundle, geoApi) {
/**
* Constructs a FeatureLayer from CSV data. Accepts the following options:
* - targetWkid: Required. an integer for an ESRI wkid the spatial reference the returned layer should be in
* - renderer: a string identifying one of the properties in defaultRenders
* - latfield: a string identifying the field containing latitude values ('Lat' by default)
* - lonfield: a string identifying the field containing longitude values ('Long' by default)
* - delimiter: a string defining the delimiter character of the file (',' by default)
* - epsgLookup: a function that takes an EPSG code (string or number) and returns a promise of a proj4 style
* definition or null if not found
* - layerId: a string to use as the layerId
* - colour: a hex string to define the symbol colour. e.g. '#33DD6A'
* @param {string} csvData the CSV data to be processed
* @param {object} opts options to be set for the parser
* @returns {Promise} a promise resolving with a {FeatureLayer}
*/
return (csvData, opts) => {
const csvOpts = { // default values
latfield: 'Lat',
lonfield: 'Long',
delimiter: ','
};
// user options if
if (opts) {
if (opts.latfield) {
csvOpts.latfield = opts.latfield;
}
if (opts.lonfield) {
csvOpts.lonfield = opts.lonfield;
}
if (opts.delimiter) {
csvOpts.delimiter = opts.delimiter;
}
}
return new Promise((resolve, reject) => {
csv2geojson.csv2geojson(csvData, csvOpts, (err, data) => {
if (err) {
console.warn('csv conversion error');
console.log(err);
reject(err);
} else {
// csv2geojson will not include the lat and long in the feature
data.features.map(feature => {
// add new property Long and Lat before layer is generated
feature.properties[csvOpts.lonfield] = feature.geometry.coordinates[0];
feature.properties[csvOpts.latfield] = feature.geometry.coordinates[1];
});
// TODO are we at risk adding params to the var that was passed in? should we make a copy and modify the copy?
opts.sourceProjection = 'EPSG:4326'; // csv is always latlong
opts.renderer = 'circlePoint'; // csv is always latlong
// NOTE: since makeGeoJsonLayer is a "built" function, grab the built version from our link to api object
geoApi.layer.makeGeoJsonLayer(data, opts).then(jsonLayer => {
resolve(jsonLayer);
});
}
});
});
};
}
/**
* Peek at the CSV output (useful for checking headers)
* @param {string} csvData the CSV data to be processed
* @param {string} delimiter the delimiter used by the data
* @returns {Array} an array of arrays containing the parsed CSV
*/
function csvPeek(csvData, delimiter) {
return csv2geojson.dsv.dsvFormat(delimiter).parseRows(csvData);
}
function makeShapeLayerBuilder(esriBundle, geoApi) {
/**
* Constructs a FeatureLayer from Shapefile data. Accepts the following options:
* - targetWkid: Required. an integer for an ESRI wkid the spatial reference the returned layer should be in
* - renderer: a string identifying one of the properties in defaultRenders
* - sourceProjection: a string matching a proj4.defs projection to be used for the source data (overrides
* geoJson.crs)
* - epsgLookup: a function that takes an EPSG code (string or number) and returns a promise of a proj4 style
* definition or null if not found
* - layerId: a string to use as the layerId
* - colour: a hex string to define the symbol colour. e.g. '#33DD6A'
* @param {ArrayBuffer} shapeData an ArrayBuffer of the Shapefile in zip format
* @param {object} opts options to be set for the parser
* @returns {Promise} a promise resolving with a {FeatureLayer}
*/
return (shapeData, opts) => {
return new Promise((resolve, reject) => {
// turn shape into geojson
shp(shapeData).then(geoJson => {
// turn geojson into feature layer
// NOTE: since makeGeoJsonLayer is a "built" function, grab the built version from our link to api object
geoApi.layer.makeGeoJsonLayer(geoJson, opts).then(jsonLayer => {
resolve(jsonLayer);
});
}).catch(err => {
reject(err);
});
});
};
}
function createImageRecordBuilder(esriBundle, geoApi, classBundle) {
/**
* Creates an Image Layer Record class
* @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)
* @returns {Object} instantited ImageRecord class
*/
return (config, esriLayer, epsgLookup) => {
return new classBundle.ImageRecord(esriBundle.ArcGISImageServiceLayer, geoApi, config, esriLayer, epsgLookup);
};
}
function createFeatureRecordBuilder(esriBundle, geoApi, classBundle) {
/**
* Creates an Feature Layer Record class
* @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)
* @returns {Object} instantited FeatureRecord class
*/
return (config, esriLayer, epsgLookup) => {
return new classBundle.FeatureRecord(esriBundle.FeatureLayer, esriBundle.esriRequest,
geoApi, config, esriLayer, epsgLookup);
};
}
function createDynamicRecordBuilder(esriBundle, geoApi, classBundle) {
/**
* Creates an Dynamic Layer Record class
* See DynamicRecord constructor for more detailed info on configIsComplete.
*
* @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)
* @param {Boolean} configIsComplete an optional flag to indicate all child state values are provided in the config and should be used.
* @returns {Object} instantited DynamicRecord class
*/
return (config, esriLayer, epsgLookup, configIsComplete = false) => {
return new classBundle.DynamicRecord(esriBundle.ArcGISDynamicMapServiceLayer, esriBundle.esriRequest,
geoApi, config, esriLayer, epsgLookup, configIsComplete);
};
}
function createTileRecordBuilder(esriBundle, geoApi, classBundle) {
/**
* Creates an Tile Layer Record class
* @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)
* @returns {Object} instantited TileRecord class
*/
return (config, esriLayer, epsgLookup) => {
return new classBundle.TileRecord(esriBundle.ArcGISTiledMapServiceLayer, geoApi, config,
esriLayer, epsgLookup);
};
}
function createWmsRecordBuilder(esriBundle, geoApi, classBundle) {
/**
* Creates an WMS Layer Record class
* @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)
* @returns {Object} instantited WmsRecord class
*/
return (config, esriLayer, epsgLookup) => {
return new classBundle.WmsRecord(esriBundle.WmsLayer, geoApi, config, esriLayer, epsgLookup);
};
}
/**
* Given 2D array in column x row format, check if all entries in the two given columns are numeric.
*
* @param {Array} arr is a 2D array based on the CSV file that contains row information for all of the rows
* @param {Integer} ind1 is a user specified index when uploading the CSV that specifies lat or long column (whichever isn't specified by ind2)
* @param {Integer} ind2 is a user specified index when uploading the CSV that specifies lat or long column (whichever isn't specified by ind1)
* @return {Boolean} returns true or false based on whether or not all all columns at ind1 and ind2 are numbers
*/
function validateLatLong(arr, ind1, ind2) {
return arr.every(row => {
return !(isNaN(row[ind1]) || isNaN(row[ind2]));
});
}
// CAREFUL NOW!
// we are passing in a reference to geoApi. it is a pointer to the object that contains this module,
// along with other modules. it lets us access other modules without re-instantiating them in here.
module.exports = function (esriBundle, geoApi) {
const layerClassBundle = layerRecord(esriBundle, geoApi);
return {
ArcGISDynamicMapServiceLayer: esriBundle.ArcGISDynamicMapServiceLayer,
ArcGISImageServiceLayer: esriBundle.ArcGISImageServiceLayer,
GraphicsLayer: esriBundle.GraphicsLayer,
FeatureLayer: esriBundle.FeatureLayer,
ScreenPoint: esriBundle.ScreenPoint,
Query: esriBundle.Query,
TileLayer: esriBundle.ArcGISTiledMapServiceLayer,
ogc: ogc(esriBundle),
bbox: bbox(esriBundle, geoApi),
createImageRecord: createImageRecordBuilder(esriBundle, geoApi, layerClassBundle),
createWmsRecord: createWmsRecordBuilder(esriBundle, geoApi, layerClassBundle),
createTileRecord: createTileRecordBuilder(esriBundle, geoApi, layerClassBundle),
createDynamicRecord: createDynamicRecordBuilder(esriBundle, geoApi, layerClassBundle),
createFeatureRecord: createFeatureRecordBuilder(esriBundle, geoApi, layerClassBundle),
LayerDrawingOptions: esriBundle.LayerDrawingOptions,
makeGeoJsonLayer: makeGeoJsonLayerBuilder(esriBundle, geoApi),
makeCsvLayer: makeCsvLayerBuilder(esriBundle, geoApi),
makeShapeLayer: makeShapeLayerBuilder(esriBundle, geoApi),
serverLayerIdentify: serverLayerIdentifyBuilder(esriBundle),
predictLayerUrl: predictLayerUrlBuilder(esriBundle),
validateFile,
csvPeek,
serviceType,
validateLatLong
};
};