mapbox-gl
Version:
A WebGL interactive maps library
338 lines (295 loc) • 12.2 kB
JavaScript
// @flow
import { Event, ErrorEvent, Evented } from '../util/evented';
import { extend } from '../util/util';
import EXTENT from '../data/extent';
import { ResourceType } from '../util/ajax';
import browser from '../util/browser';
import type {Source} from './source';
import type Map from '../ui/map';
import type Dispatcher from '../util/dispatcher';
import type Tile from './tile';
import type {Callback} from '../types/callback';
import type {GeoJSON, GeoJSONFeature} from '@mapbox/geojson-types';
import type {GeoJSONSourceSpecification} from '../style-spec/types';
/**
* A source containing GeoJSON.
* (See the [Style Specification](https://www.mapbox.com/mapbox-gl-style-spec/#sources-geojson) for detailed documentation of options.)
*
* @example
* map.addSource('some id', {
* type: 'geojson',
* data: 'https://d2ad6b4ur7yvpq.cloudfront.net/naturalearth-3.3.0/ne_10m_ports.geojson'
* });
*
* @example
* map.addSource('some id', {
* type: 'geojson',
* data: {
* "type": "FeatureCollection",
* "features": [{
* "type": "Feature",
* "properties": {},
* "geometry": {
* "type": "Point",
* "coordinates": [
* -76.53063297271729,
* 39.18174077994108
* ]
* }
* }]
* }
* });
*
* @example
* map.getSource('some id').setData({
* "type": "FeatureCollection",
* "features": [{
* "type": "Feature",
* "properties": { "name": "Null Island" },
* "geometry": {
* "type": "Point",
* "coordinates": [ 0, 0 ]
* }
* }]
* });
* @see [Draw GeoJSON points](https://www.mapbox.com/mapbox-gl-js/example/geojson-markers/)
* @see [Add a GeoJSON line](https://www.mapbox.com/mapbox-gl-js/example/geojson-line/)
* @see [Create a heatmap from points](https://www.mapbox.com/mapbox-gl-js/example/heatmap/)
* @see [Create and style clusters](https://www.mapbox.com/mapbox-gl-js/example/cluster/)
*/
class GeoJSONSource extends Evented implements Source {
type: 'geojson';
id: string;
minzoom: number;
maxzoom: number;
tileSize: number;
attribution: string;
isTileClipped: boolean;
reparseOverscaled: boolean;
_data: GeoJSON | string;
_options: any;
workerOptions: any;
dispatcher: Dispatcher;
map: Map;
workerID: number;
_loaded: boolean;
_collectResourceTiming: boolean;
_resourceTiming: Array<PerformanceResourceTiming>;
_removed: boolean;
/**
* @private
*/
constructor(id: string, options: GeoJSONSourceSpecification & {workerOptions?: any, collectResourceTiming: boolean}, dispatcher: Dispatcher, eventedParent: Evented) {
super();
this.id = id;
// `type` is a property rather than a constant to make it easy for 3rd
// parties to use GeoJSONSource to build their own source types.
this.type = 'geojson';
this.minzoom = 0;
this.maxzoom = 18;
this.tileSize = 512;
this.isTileClipped = true;
this.reparseOverscaled = true;
this._removed = false;
this.dispatcher = dispatcher;
this.setEventedParent(eventedParent);
this._data = (options.data: any);
this._options = extend({}, options);
this._collectResourceTiming = options.collectResourceTiming;
this._resourceTiming = [];
if (options.maxzoom !== undefined) this.maxzoom = options.maxzoom;
if (options.type) this.type = options.type;
if (options.attribution) this.attribution = options.attribution;
const scale = EXTENT / this.tileSize;
// sent to the worker, along with `url: ...` or `data: literal geojson`,
// so that it can load/parse/index the geojson data
// extending with `options.workerOptions` helps to make it easy for
// third-party sources to hack/reuse GeoJSONSource.
this.workerOptions = extend({
source: this.id,
cluster: options.cluster || false,
geojsonVtOptions: {
buffer: (options.buffer !== undefined ? options.buffer : 128) * scale,
tolerance: (options.tolerance !== undefined ? options.tolerance : 0.375) * scale,
extent: EXTENT,
maxZoom: this.maxzoom,
lineMetrics: options.lineMetrics || false,
generateId: options.generateId || false
},
superclusterOptions: {
maxZoom: options.clusterMaxZoom !== undefined ?
Math.min(options.clusterMaxZoom, this.maxzoom - 1) :
(this.maxzoom - 1),
extent: EXTENT,
radius: (options.clusterRadius || 50) * scale,
log: false
},
clusterProperties: options.clusterProperties
}, options.workerOptions);
}
load() {
this.fire(new Event('dataloading', {dataType: 'source'}));
this._updateWorkerData((err) => {
if (err) {
this.fire(new ErrorEvent(err));
return;
}
const data: Object = { dataType: 'source', sourceDataType: 'metadata' };
if (this._collectResourceTiming && this._resourceTiming && (this._resourceTiming.length > 0)) {
data.resourceTiming = this._resourceTiming;
this._resourceTiming = [];
}
// although GeoJSON sources contain no metadata, we fire this event to let the SourceCache
// know its ok to start requesting tiles.
this.fire(new Event('data', data));
});
}
onAdd(map: Map) {
this.map = map;
this.load();
}
/**
* Sets the GeoJSON data and re-renders the map.
*
* @param {Object|string} data A GeoJSON data object or a URL to one. The latter is preferable in the case of large GeoJSON files.
* @returns {GeoJSONSource} this
*/
setData(data: GeoJSON | string) {
this._data = data;
this.fire(new Event('dataloading', {dataType: 'source'}));
this._updateWorkerData((err) => {
if (err) {
this.fire(new ErrorEvent(err));
return;
}
const data: Object = { dataType: 'source', sourceDataType: 'content' };
if (this._collectResourceTiming && this._resourceTiming && (this._resourceTiming.length > 0)) {
data.resourceTiming = this._resourceTiming;
this._resourceTiming = [];
}
this.fire(new Event('data', data));
});
return this;
}
/**
* For clustered sources, fetches the zoom at which the given cluster expands.
*
* @param clusterId The value of the cluster's `cluster_id` property.
* @param callback A callback to be called when the zoom value is retrieved (`(error, zoom) => { ... }`).
* @returns {GeoJSONSource} this
*/
getClusterExpansionZoom(clusterId: number, callback: Callback<number>) {
this.dispatcher.send('geojson.getClusterExpansionZoom', { clusterId, source: this.id }, callback, this.workerID);
return this;
}
/**
* For clustered sources, fetches the children of the given cluster on the next zoom level (as an array of GeoJSON features).
*
* @param clusterId The value of the cluster's `cluster_id` property.
* @param callback A callback to be called when the features are retrieved (`(error, features) => { ... }`).
* @returns {GeoJSONSource} this
*/
getClusterChildren(clusterId: number, callback: Callback<Array<GeoJSONFeature>>) {
this.dispatcher.send('geojson.getClusterChildren', { clusterId, source: this.id }, callback, this.workerID);
return this;
}
/**
* For clustered sources, fetches the original points that belong to the cluster (as an array of GeoJSON features).
*
* @param clusterId The value of the cluster's `cluster_id` property.
* @param limit The maximum number of features to return.
* @param offset The number of features to skip (e.g. for pagination).
* @param callback A callback to be called when the features are retrieved (`(error, features) => { ... }`).
* @returns {GeoJSONSource} this
*/
getClusterLeaves(clusterId: number, limit: number, offset: number, callback: Callback<Array<GeoJSONFeature>>) {
this.dispatcher.send('geojson.getClusterLeaves', {
source: this.id,
clusterId,
limit,
offset
}, callback, this.workerID);
return this;
}
/*
* Responsible for invoking WorkerSource's geojson.loadData target, which
* handles loading the geojson data and preparing to serve it up as tiles,
* using geojson-vt or supercluster as appropriate.
*/
_updateWorkerData(callback: Callback<void>) {
const options = extend({}, this.workerOptions);
const data = this._data;
if (typeof data === 'string') {
options.request = this.map._requestManager.transformRequest(browser.resolveURL(data), ResourceType.Source);
options.request.collectResourceTiming = this._collectResourceTiming;
} else {
options.data = JSON.stringify(data);
}
// target {this.type}.loadData rather than literally geojson.loadData,
// so that other geojson-like source types can easily reuse this
// implementation
this.workerID = this.dispatcher.send(`${this.type}.loadData`, options, (err, result) => {
if (this._removed || (result && result.abandoned)) {
return;
}
this._loaded = true;
if (result && result.resourceTiming && result.resourceTiming[this.id])
this._resourceTiming = result.resourceTiming[this.id].slice(0);
// Any `loadData` calls that piled up while we were processing
// this one will get coalesced into a single call when this
// 'coalesce' message is processed.
// We would self-send from the worker if we had access to its
// message queue. Waiting instead for the 'coalesce' to round-trip
// through the foreground just means we're throttling the worker
// to run at a little less than full-throttle.
this.dispatcher.send(`${this.type}.coalesce`, { source: options.source }, null, this.workerID);
callback(err);
}, this.workerID);
}
loadTile(tile: Tile, callback: Callback<void>) {
const message = tile.workerID === undefined ? 'loadTile' : 'reloadTile';
const params = {
type: this.type,
uid: tile.uid,
tileID: tile.tileID,
zoom: tile.tileID.overscaledZ,
maxZoom: this.maxzoom,
tileSize: this.tileSize,
source: this.id,
pixelRatio: browser.devicePixelRatio,
showCollisionBoxes: this.map.showCollisionBoxes
};
tile.workerID = this.dispatcher.send(message, params, (err, data) => {
tile.unloadVectorData();
if (tile.aborted) {
return callback(null);
}
if (err) {
return callback(err);
}
tile.loadVectorData(data, this.map.painter, message === 'reloadTile');
return callback(null);
}, this.workerID);
}
abortTile(tile: Tile) {
tile.aborted = true;
}
unloadTile(tile: Tile) {
tile.unloadVectorData();
this.dispatcher.send('removeTile', { uid: tile.uid, type: this.type, source: this.id }, null, tile.workerID);
}
onRemove() {
this._removed = true;
this.dispatcher.send('removeSource', { type: this.type, source: this.id }, null, this.workerID);
}
serialize() {
return extend({}, this._options, {
type: this.type,
data: this._data
});
}
hasTransition() {
return false;
}
}
export default GeoJSONSource;