Files
openlayers/src/ol/source/WMTS.js
2018-11-16 14:05:06 +01:00

526 lines
16 KiB
JavaScript

/**
* @module ol/source/WMTS
*/
import {expandUrl, createFromTileUrlFunctions, nullTileUrlFunction} from '../tileurlfunction.js';
import {find, findIndex, includes} from '../array.js';
import {containsExtent} from '../extent.js';
import {assign} from '../obj.js';
import {get as getProjection, equivalent, transformExtent} from '../proj.js';
import TileImage from './TileImage.js';
import WMTSRequestEncoding from './WMTSRequestEncoding.js';
import {createFromCapabilitiesMatrixSet} from '../tilegrid/WMTS.js';
import {appendParams} from '../uri.js';
/**
* @typedef {Object} Options
* @property {import("./Source.js").AttributionLike} [attributions] Attributions.
* @property {number} [cacheSize=2048] Cache size.
* @property {null|string} [crossOrigin] The `crossOrigin` attribute for loaded images. Note that
* you must provide a `crossOrigin` value if you want to access pixel data with the Canvas renderer.
* See https://developer.mozilla.org/en-US/docs/Web/HTML/CORS_enabled_image for more detail.
* @property {import("../tilegrid/WMTS.js").default} tileGrid Tile grid.
* @property {import("../proj.js").ProjectionLike} projection Projection.
* @property {number} [reprojectionErrorThreshold=0.5] Maximum allowed reprojection error (in pixels).
* Higher values can increase reprojection performance, but decrease precision.
* @property {import("./WMTSRequestEncoding.js").default|string} [requestEncoding='KVP'] Request encoding.
* @property {string} layer Layer name as advertised in the WMTS capabilities.
* @property {string} style Style name as advertised in the WMTS capabilities.
* @property {typeof import("../ImageTile.js").default} [tileClass] Class used to instantiate image tiles. Default is {@link module:ol/ImageTile~ImageTile}.
* @property {number} [tilePixelRatio=1] The pixel ratio used by the tile service.
* For example, if the tile service advertizes 256px by 256px tiles but actually sends 512px
* by 512px images (for retina/hidpi devices) then `tilePixelRatio`
* should be set to `2`.
* @property {string} [format='image/jpeg'] Image format. Only used when `requestEncoding` is `'KVP'`.
* @property {string} [version='1.0.0'] WMTS version.
* @property {string} matrixSet Matrix set.
* @property {!Object} [dimensions] Additional "dimensions" for tile requests.
* This is an object with properties named like the advertised WMTS dimensions.
* @property {string} [url] A URL for the service.
* For the RESTful request encoding, this is a URL
* template. For KVP encoding, it is normal URL. A `{?-?}` template pattern,
* for example `subdomain{a-f}.domain.com`, may be used instead of defining
* each one separately in the `urls` option.
* @property {import("../Tile.js").LoadFunction} [tileLoadFunction] Optional function to load a tile given a URL. The default is
* ```js
* function(imageTile, src) {
* imageTile.getImage().src = src;
* };
* ```
* @property {Array<string>} [urls] An array of URLs.
* Requests will be distributed among the URLs in this array.
* @property {boolean} [wrapX=false] Whether to wrap the world horizontally.
* @property {number} [transition] Duration of the opacity transition for rendering.
* To disable the opacity transition, pass `transition: 0`.
*/
/**
* @classdesc
* Layer source for tile data from WMTS servers.
* @api
*/
class WMTS extends TileImage {
/**
* @param {Options} options WMTS options.
*/
constructor(options) {
// TODO: add support for TileMatrixLimits
const requestEncoding = options.requestEncoding !== undefined ?
/** @type {import("./WMTSRequestEncoding.js").default} */ (options.requestEncoding) :
WMTSRequestEncoding.KVP;
// FIXME: should we create a default tileGrid?
// we could issue a getCapabilities xhr to retrieve missing configuration
const tileGrid = options.tileGrid;
let urls = options.urls;
if (urls === undefined && options.url !== undefined) {
urls = expandUrl(options.url);
}
super({
attributions: options.attributions,
cacheSize: options.cacheSize,
crossOrigin: options.crossOrigin,
projection: options.projection,
reprojectionErrorThreshold: options.reprojectionErrorThreshold,
tileClass: options.tileClass,
tileGrid: tileGrid,
tileLoadFunction: options.tileLoadFunction,
tilePixelRatio: options.tilePixelRatio,
tileUrlFunction: nullTileUrlFunction,
urls: urls,
wrapX: options.wrapX !== undefined ? options.wrapX : false,
transition: options.transition
});
/**
* @private
* @type {string}
*/
this.version_ = options.version !== undefined ? options.version : '1.0.0';
/**
* @private
* @type {string}
*/
this.format_ = options.format !== undefined ? options.format : 'image/jpeg';
/**
* @private
* @type {!Object}
*/
this.dimensions_ = options.dimensions !== undefined ? options.dimensions : {};
/**
* @private
* @type {string}
*/
this.layer_ = options.layer;
/**
* @private
* @type {string}
*/
this.matrixSet_ = options.matrixSet;
/**
* @private
* @type {string}
*/
this.style_ = options.style;
// FIXME: should we guess this requestEncoding from options.url(s)
// structure? that would mean KVP only if a template is not provided.
/**
* @private
* @type {import("./WMTSRequestEncoding.js").default}
*/
this.requestEncoding_ = requestEncoding;
this.setKey(this.getKeyForDimensions_());
if (urls && urls.length > 0) {
this.tileUrlFunction = createFromTileUrlFunctions(urls.map(createFromWMTSTemplate.bind(this)));
}
}
/**
* Set the URLs to use for requests.
* URLs may contain OCG conform URL Template Variables: {TileMatrix}, {TileRow}, {TileCol}.
* @override
*/
setUrls(urls) {
this.urls = urls;
const key = urls.join('\n');
this.setTileUrlFunction(createFromTileUrlFunctions(urls.map(createFromWMTSTemplate.bind(this))), key);
}
/**
* Get the dimensions, i.e. those passed to the constructor through the
* "dimensions" option, and possibly updated using the updateDimensions
* method.
* @return {!Object} Dimensions.
* @api
*/
getDimensions() {
return this.dimensions_;
}
/**
* Return the image format of the WMTS source.
* @return {string} Format.
* @api
*/
getFormat() {
return this.format_;
}
/**
* Return the layer of the WMTS source.
* @return {string} Layer.
* @api
*/
getLayer() {
return this.layer_;
}
/**
* Return the matrix set of the WMTS source.
* @return {string} MatrixSet.
* @api
*/
getMatrixSet() {
return this.matrixSet_;
}
/**
* Return the request encoding, either "KVP" or "REST".
* @return {import("./WMTSRequestEncoding.js").default} Request encoding.
* @api
*/
getRequestEncoding() {
return this.requestEncoding_;
}
/**
* Return the style of the WMTS source.
* @return {string} Style.
* @api
*/
getStyle() {
return this.style_;
}
/**
* Return the version of the WMTS source.
* @return {string} Version.
* @api
*/
getVersion() {
return this.version_;
}
/**
* @private
* @return {string} The key for the current dimensions.
*/
getKeyForDimensions_() {
let i = 0;
const res = [];
for (const key in this.dimensions_) {
res[i++] = key + '-' + this.dimensions_[key];
}
return res.join('/');
}
/**
* Update the dimensions.
* @param {Object} dimensions Dimensions.
* @api
*/
updateDimensions(dimensions) {
assign(this.dimensions_, dimensions);
this.setKey(this.getKeyForDimensions_());
}
}
export default WMTS;
/**
* Generate source options from a capabilities object.
* @param {Object} wmtsCap An object representing the capabilities document.
* @param {!Object} config Configuration properties for the layer. Defaults for
* the layer will apply if not provided.
*
* Required config properties:
* - layer - {string} The layer identifier.
*
* Optional config properties:
* - matrixSet - {string} The matrix set identifier, required if there is
* more than one matrix set in the layer capabilities.
* - projection - {string} The desired CRS when no matrixSet is specified.
* eg: "EPSG:3857". If the desired projection is not available,
* an error is thrown.
* - requestEncoding - {string} url encoding format for the layer. Default is
* the first tile url format found in the GetCapabilities response.
* - style - {string} The name of the style
* - format - {string} Image format for the layer. Default is the first
* format returned in the GetCapabilities response.
* - crossOrigin - {string|null|undefined} Cross origin. Default is `undefined`.
* @return {?Options} WMTS source options object or `null` if the layer was not found.
* @api
*/
export function optionsFromCapabilities(wmtsCap, config) {
const layers = wmtsCap['Contents']['Layer'];
const l = find(layers, function(elt, index, array) {
return elt['Identifier'] == config['layer'];
});
if (l === null) {
return null;
}
const tileMatrixSets = wmtsCap['Contents']['TileMatrixSet'];
let idx;
if (l['TileMatrixSetLink'].length > 1) {
if ('projection' in config) {
idx = findIndex(l['TileMatrixSetLink'],
function(elt, index, array) {
const tileMatrixSet = find(tileMatrixSets, function(el) {
return el['Identifier'] == elt['TileMatrixSet'];
});
const supportedCRS = tileMatrixSet['SupportedCRS'];
const proj1 = getProjection(supportedCRS.replace(/urn:ogc:def:crs:(\w+):(.*:)?(\w+)$/, '$1:$3')) ||
getProjection(supportedCRS);
const proj2 = getProjection(config['projection']);
if (proj1 && proj2) {
return equivalent(proj1, proj2);
} else {
return supportedCRS == config['projection'];
}
});
} else {
idx = findIndex(l['TileMatrixSetLink'],
function(elt, index, array) {
return elt['TileMatrixSet'] == config['matrixSet'];
});
}
} else {
idx = 0;
}
if (idx < 0) {
idx = 0;
}
const matrixSet = /** @type {string} */
(l['TileMatrixSetLink'][idx]['TileMatrixSet']);
const matrixLimits = /** @type {Array<Object>} */
(l['TileMatrixSetLink'][idx]['TileMatrixSetLimits']);
let format = /** @type {string} */ (l['Format'][0]);
if ('format' in config) {
format = config['format'];
}
idx = findIndex(l['Style'], function(elt, index, array) {
if ('style' in config) {
return elt['Title'] == config['style'];
} else {
return elt['isDefault'];
}
});
if (idx < 0) {
idx = 0;
}
const style = /** @type {string} */ (l['Style'][idx]['Identifier']);
const dimensions = {};
if ('Dimension' in l) {
l['Dimension'].forEach(function(elt, index, array) {
const key = elt['Identifier'];
let value = elt['Default'];
if (value === undefined) {
value = elt['Value'][0];
}
dimensions[key] = value;
});
}
const matrixSets = wmtsCap['Contents']['TileMatrixSet'];
const matrixSetObj = find(matrixSets, function(elt, index, array) {
return elt['Identifier'] == matrixSet;
});
let projection;
const code = matrixSetObj['SupportedCRS'];
if (code) {
projection = getProjection(code.replace(/urn:ogc:def:crs:(\w+):(.*:)?(\w+)$/, '$1:$3')) ||
getProjection(code);
}
if ('projection' in config) {
const projConfig = getProjection(config['projection']);
if (projConfig) {
if (!projection || equivalent(projConfig, projection)) {
projection = projConfig;
}
}
}
const wgs84BoundingBox = l['WGS84BoundingBox'];
let extent, wrapX;
if (wgs84BoundingBox !== undefined) {
const wgs84ProjectionExtent = getProjection('EPSG:4326').getExtent();
wrapX = (wgs84BoundingBox[0] == wgs84ProjectionExtent[0] &&
wgs84BoundingBox[2] == wgs84ProjectionExtent[2]);
extent = transformExtent(
wgs84BoundingBox, 'EPSG:4326', projection);
const projectionExtent = projection.getExtent();
if (projectionExtent) {
// If possible, do a sanity check on the extent - it should never be
// bigger than the validity extent of the projection of a matrix set.
if (!containsExtent(projectionExtent, extent)) {
extent = undefined;
}
}
}
const tileGrid = createFromCapabilitiesMatrixSet(matrixSetObj, extent, matrixLimits);
/** @type {!Array<string>} */
const urls = [];
let requestEncoding = config['requestEncoding'];
requestEncoding = requestEncoding !== undefined ? requestEncoding : '';
if ('OperationsMetadata' in wmtsCap && 'GetTile' in wmtsCap['OperationsMetadata']) {
const gets = wmtsCap['OperationsMetadata']['GetTile']['DCP']['HTTP']['Get'];
for (let i = 0, ii = gets.length; i < ii; ++i) {
if (gets[i]['Constraint']) {
const constraint = find(gets[i]['Constraint'], function(element) {
return element['name'] == 'GetEncoding';
});
const encodings = constraint['AllowedValues']['Value'];
if (requestEncoding === '') {
// requestEncoding not provided, use the first encoding from the list
requestEncoding = encodings[0];
}
if (requestEncoding === WMTSRequestEncoding.KVP) {
if (includes(encodings, WMTSRequestEncoding.KVP)) {
urls.push(/** @type {string} */ (gets[i]['href']));
}
} else {
break;
}
} else if (gets[i]['href']) {
requestEncoding = WMTSRequestEncoding.KVP;
urls.push(/** @type {string} */ (gets[i]['href']));
}
}
}
if (urls.length === 0) {
requestEncoding = WMTSRequestEncoding.REST;
l['ResourceURL'].forEach(function(element) {
if (element['resourceType'] === 'tile') {
format = element['format'];
urls.push(/** @type {string} */ (element['template']));
}
});
}
return {
urls: urls,
layer: config['layer'],
matrixSet: matrixSet,
format: format,
projection: projection,
requestEncoding: requestEncoding,
tileGrid: tileGrid,
style: style,
dimensions: dimensions,
wrapX: wrapX,
crossOrigin: config['crossOrigin']
};
}
/**
* @param {string} template Template.
* @return {import("../Tile.js").UrlFunction} Tile URL function.
* @this {WMTS}
*/
function createFromWMTSTemplate(template) {
const requestEncoding = this.requestEncoding_;
// context property names are lower case to allow for a case insensitive
// replacement as some services use different naming conventions
const context = {
'layer': this.layer_,
'style': this.style_,
'tilematrixset': this.matrixSet_
};
if (requestEncoding == WMTSRequestEncoding.KVP) {
assign(context, {
'Service': 'WMTS',
'Request': 'GetTile',
'Version': this.version_,
'Format': this.format_
});
}
// TODO: we may want to create our own appendParams function so that params
// order conforms to wmts spec guidance, and so that we can avoid to escape
// special template params
template = (requestEncoding == WMTSRequestEncoding.KVP) ?
appendParams(template, context) :
template.replace(/\{(\w+?)\}/g, function(m, p) {
return (p.toLowerCase() in context) ? context[p.toLowerCase()] : m;
});
const tileGrid = /** @type {import("../tilegrid/WMTS.js").default} */ (
this.tileGrid);
const dimensions = this.dimensions_;
return (
/**
* @param {import("../tilecoord.js").TileCoord} tileCoord Tile coordinate.
* @param {number} pixelRatio Pixel ratio.
* @param {import("../proj/Projection.js").default} projection Projection.
* @return {string|undefined} Tile URL.
*/
function(tileCoord, pixelRatio, projection) {
if (!tileCoord) {
return undefined;
} else {
const localContext = {
'TileMatrix': tileGrid.getMatrixId(tileCoord[0]),
'TileCol': tileCoord[1],
'TileRow': -tileCoord[2] - 1
};
assign(localContext, dimensions);
let url = template;
if (requestEncoding == WMTSRequestEncoding.KVP) {
url = appendParams(url, localContext);
} else {
url = url.replace(/\{(\w+?)\}/g, function(m, p) {
return localContext[p];
});
}
return url;
}
}
);
}