uriproj
Version:
Map projection functions from standard coordinate reference system URIs.
637 lines (550 loc) • 19.8 kB
JavaScript
(function (exports,proj4) {
'use strict';
proj4 = 'default' in proj4 ? proj4['default'] : proj4;
(function(self) {
'use strict';
if (self.fetch) {
return
}
var support = {
searchParams: 'URLSearchParams' in self,
iterable: 'Symbol' in self && 'iterator' in Symbol,
blob: 'FileReader' in self && 'Blob' in self && (function() {
try {
new Blob()
return true
} catch(e) {
return false
}
})(),
formData: 'FormData' in self,
arrayBuffer: 'ArrayBuffer' in self
}
function normalizeName(name) {
if (typeof name !== 'string') {
name = String(name)
}
if (/[^a-z0-9\-#$%&'*+.\^_`|~]/i.test(name)) {
throw new TypeError('Invalid character in header field name')
}
return name.toLowerCase()
}
function normalizeValue(value) {
if (typeof value !== 'string') {
value = String(value)
}
return value
}
// Build a destructive iterator for the value list
function iteratorFor(items) {
var iterator = {
next: function() {
var value = items.shift()
return {done: value === undefined, value: value}
}
}
if (support.iterable) {
iterator[Symbol.iterator] = function() {
return iterator
}
}
return iterator
}
function Headers(headers) {
this.map = {}
if (headers instanceof Headers) {
headers.forEach(function(value, name) {
this.append(name, value)
}, this)
} else if (headers) {
Object.getOwnPropertyNames(headers).forEach(function(name) {
this.append(name, headers[name])
}, this)
}
}
Headers.prototype.append = function(name, value) {
name = normalizeName(name)
value = normalizeValue(value)
var list = this.map[name]
if (!list) {
list = []
this.map[name] = list
}
list.push(value)
}
Headers.prototype['delete'] = function(name) {
delete this.map[normalizeName(name)]
}
Headers.prototype.get = function(name) {
var values = this.map[normalizeName(name)]
return values ? values[0] : null
}
Headers.prototype.getAll = function(name) {
return this.map[normalizeName(name)] || []
}
Headers.prototype.has = function(name) {
return this.map.hasOwnProperty(normalizeName(name))
}
Headers.prototype.set = function(name, value) {
this.map[normalizeName(name)] = [normalizeValue(value)]
}
Headers.prototype.forEach = function(callback, thisArg) {
Object.getOwnPropertyNames(this.map).forEach(function(name) {
this.map[name].forEach(function(value) {
callback.call(thisArg, value, name, this)
}, this)
}, this)
}
Headers.prototype.keys = function() {
var items = []
this.forEach(function(value, name) { items.push(name) })
return iteratorFor(items)
}
Headers.prototype.values = function() {
var items = []
this.forEach(function(value) { items.push(value) })
return iteratorFor(items)
}
Headers.prototype.entries = function() {
var items = []
this.forEach(function(value, name) { items.push([name, value]) })
return iteratorFor(items)
}
if (support.iterable) {
Headers.prototype[Symbol.iterator] = Headers.prototype.entries
}
function consumed(body) {
if (body.bodyUsed) {
return Promise.reject(new TypeError('Already read'))
}
body.bodyUsed = true
}
function fileReaderReady(reader) {
return new Promise(function(resolve, reject) {
reader.onload = function() {
resolve(reader.result)
}
reader.onerror = function() {
reject(reader.error)
}
})
}
function readBlobAsArrayBuffer(blob) {
var reader = new FileReader()
reader.readAsArrayBuffer(blob)
return fileReaderReady(reader)
}
function readBlobAsText(blob) {
var reader = new FileReader()
reader.readAsText(blob)
return fileReaderReady(reader)
}
function Body() {
this.bodyUsed = false
this._initBody = function(body) {
this._bodyInit = body
if (typeof body === 'string') {
this._bodyText = body
} else if (support.blob && Blob.prototype.isPrototypeOf(body)) {
this._bodyBlob = body
} else if (support.formData && FormData.prototype.isPrototypeOf(body)) {
this._bodyFormData = body
} else if (support.searchParams && URLSearchParams.prototype.isPrototypeOf(body)) {
this._bodyText = body.toString()
} else if (!body) {
this._bodyText = ''
} else if (support.arrayBuffer && ArrayBuffer.prototype.isPrototypeOf(body)) {
// Only support ArrayBuffers for POST method.
// Receiving ArrayBuffers happens via Blobs, instead.
} else {
throw new Error('unsupported BodyInit type')
}
if (!this.headers.get('content-type')) {
if (typeof body === 'string') {
this.headers.set('content-type', 'text/plain;charset=UTF-8')
} else if (this._bodyBlob && this._bodyBlob.type) {
this.headers.set('content-type', this._bodyBlob.type)
} else if (support.searchParams && URLSearchParams.prototype.isPrototypeOf(body)) {
this.headers.set('content-type', 'application/x-www-form-urlencoded;charset=UTF-8')
}
}
}
if (support.blob) {
this.blob = function() {
var rejected = consumed(this)
if (rejected) {
return rejected
}
if (this._bodyBlob) {
return Promise.resolve(this._bodyBlob)
} else if (this._bodyFormData) {
throw new Error('could not read FormData body as blob')
} else {
return Promise.resolve(new Blob([this._bodyText]))
}
}
this.arrayBuffer = function() {
return this.blob().then(readBlobAsArrayBuffer)
}
this.text = function() {
var rejected = consumed(this)
if (rejected) {
return rejected
}
if (this._bodyBlob) {
return readBlobAsText(this._bodyBlob)
} else if (this._bodyFormData) {
throw new Error('could not read FormData body as text')
} else {
return Promise.resolve(this._bodyText)
}
}
} else {
this.text = function() {
var rejected = consumed(this)
return rejected ? rejected : Promise.resolve(this._bodyText)
}
}
if (support.formData) {
this.formData = function() {
return this.text().then(decode)
}
}
this.json = function() {
return this.text().then(JSON.parse)
}
return this
}
// HTTP methods whose capitalization should be normalized
var methods = ['DELETE', 'GET', 'HEAD', 'OPTIONS', 'POST', 'PUT']
function normalizeMethod(method) {
var upcased = method.toUpperCase()
return (methods.indexOf(upcased) > -1) ? upcased : method
}
function Request(input, options) {
options = options || {}
var body = options.body
if (Request.prototype.isPrototypeOf(input)) {
if (input.bodyUsed) {
throw new TypeError('Already read')
}
this.url = input.url
this.credentials = input.credentials
if (!options.headers) {
this.headers = new Headers(input.headers)
}
this.method = input.method
this.mode = input.mode
if (!body) {
body = input._bodyInit
input.bodyUsed = true
}
} else {
this.url = input
}
this.credentials = options.credentials || this.credentials || 'omit'
if (options.headers || !this.headers) {
this.headers = new Headers(options.headers)
}
this.method = normalizeMethod(options.method || this.method || 'GET')
this.mode = options.mode || this.mode || null
this.referrer = null
if ((this.method === 'GET' || this.method === 'HEAD') && body) {
throw new TypeError('Body not allowed for GET or HEAD requests')
}
this._initBody(body)
}
Request.prototype.clone = function() {
return new Request(this)
}
function decode(body) {
var form = new FormData()
body.trim().split('&').forEach(function(bytes) {
if (bytes) {
var split = bytes.split('=')
var name = split.shift().replace(/\+/g, ' ')
var value = split.join('=').replace(/\+/g, ' ')
form.append(decodeURIComponent(name), decodeURIComponent(value))
}
})
return form
}
function headers(xhr) {
var head = new Headers()
var pairs = (xhr.getAllResponseHeaders() || '').trim().split('\n')
pairs.forEach(function(header) {
var split = header.trim().split(':')
var key = split.shift().trim()
var value = split.join(':').trim()
head.append(key, value)
})
return head
}
Body.call(Request.prototype)
function Response(bodyInit, options) {
if (!options) {
options = {}
}
this.type = 'default'
this.status = options.status
this.ok = this.status >= 200 && this.status < 300
this.statusText = options.statusText
this.headers = options.headers instanceof Headers ? options.headers : new Headers(options.headers)
this.url = options.url || ''
this._initBody(bodyInit)
}
Body.call(Response.prototype)
Response.prototype.clone = function() {
return new Response(this._bodyInit, {
status: this.status,
statusText: this.statusText,
headers: new Headers(this.headers),
url: this.url
})
}
Response.error = function() {
var response = new Response(null, {status: 0, statusText: ''})
response.type = 'error'
return response
}
var redirectStatuses = [301, 302, 303, 307, 308]
Response.redirect = function(url, status) {
if (redirectStatuses.indexOf(status) === -1) {
throw new RangeError('Invalid status code')
}
return new Response(null, {status: status, headers: {location: url}})
}
self.Headers = Headers
self.Request = Request
self.Response = Response
self.fetch = function(input, init) {
return new Promise(function(resolve, reject) {
var request
if (Request.prototype.isPrototypeOf(input) && !init) {
request = input
} else {
request = new Request(input, init)
}
var xhr = new XMLHttpRequest()
function responseURL() {
if ('responseURL' in xhr) {
return xhr.responseURL
}
// Avoid security warnings on getResponseHeader when not allowed by CORS
if (/^X-Request-URL:/m.test(xhr.getAllResponseHeaders())) {
return xhr.getResponseHeader('X-Request-URL')
}
return
}
xhr.onload = function() {
var options = {
status: xhr.status,
statusText: xhr.statusText,
headers: headers(xhr),
url: responseURL()
}
var body = 'response' in xhr ? xhr.response : xhr.responseText
resolve(new Response(body, options))
}
xhr.onerror = function() {
reject(new TypeError('Network request failed'))
}
xhr.ontimeout = function() {
reject(new TypeError('Network request failed'))
}
xhr.open(request.method, request.url, true)
if (request.credentials === 'include') {
xhr.withCredentials = true
}
if ('responseType' in xhr && support.blob) {
xhr.responseType = 'blob'
}
request.headers.forEach(function(value, name) {
xhr.setRequestHeader(name, value)
})
xhr.send(typeof request._bodyInit === 'undefined' ? null : request._bodyInit)
})
}
self.fetch.polyfill = true
})(typeof self !== 'undefined' ? self : this);
var defineProperty = function (obj, key, value) {
if (key in obj) {
Object.defineProperty(obj, key, {
value: value,
enumerable: true,
configurable: true,
writable: true
});
} else {
obj[key] = value;
}
return obj;
};
var ROOT_PREFIX = 'http://www.opengis.net/def/crs/';
var OGC_PREFIX = ROOT_PREFIX + 'OGC/';
var EPSG_PREFIX = ROOT_PREFIX + 'EPSG/0/';
/**
* @typedef {Object} Projection
* @property {function(lonlat: Array<number>): Array<number>} forward
* Transforms a geographic WGS84 [longitude, latitude] coordinate to an [x, y] projection coordinate.
* @property {function(xy: Array<number>): Array<number>} inverse
* Transforms an [x, y] projection coordinate to a geographic WGS84 [longitude, latitude] coordinate.
*/
// a cache of URI string -> Projection object mappings
var projCache = {};
// work-arounds for incorrect epsg.io / proj4 behaviour
var needsAxesReordering = defineProperty({}, EPSG_PREFIX + 4326, true);
// store some built-in projections which are not available on epsg.io
var LONLAT = proj4('+proj=longlat +datum=WGS84 +no_defs');
set(OGC_PREFIX + '1.3/CRS84', LONLAT);
set(EPSG_PREFIX + 4979, reverseAxes(LONLAT));
/**
* Returns a stored {@link Projection} for a given URI, or {@link undefined} if no {@link Projection} is stored for that URI.
*
* @param {string} crsUri The CRS URI for which to return a {@link Projection}.
* @return {Projection|undefined} A {@link Projection} object, or {@link undefined} if not stored by {@link load} or {@link set}.
*
* @example
* // has to be stored previously via load() or set()
* var proj = uriproj.get('http://www.opengis.net/def/crs/EPSG/0/27700')
* var [longitude, latitude] = [-1.54, 55.5]
* var [easting,northing] = proj.forward([longitude, latitude])
*/
function get(crsUri) {
return projCache[crsUri];
}
/**
* Returns a {@link Promise} that succeeds with an already stored {@link Projection} or, if not stored,
* that remotely loads the {@link Projection} (currently using https://epsg.io), stores it, and then succeeds with it.
*
* @param {string} crsUri The CRS URI for which to return a projection.
* @return {Promise<Projection,Error>} A {@link Promise} object succeeding with a {@link Projection} object,
* and failing with an {@link Error} object in case of network or PROJ.4 parsing problems.
*
* @example <caption>Loading a single projection</caption>
* uriproj.load('http://www.opengis.net/def/crs/EPSG/0/27700').then(proj => {
* var [longitude, latitude] = [-1.54, 55.5]
* var [easting,northing] = proj.forward([longitude, latitude])
* })
*
* @example <caption>Loading multiple projections</caption>
* var uris = [
* 'http://www.opengis.net/def/crs/EPSG/0/27700',
* 'http://www.opengis.net/def/crs/EPSG/0/7376',
* 'http://www.opengis.net/def/crs/EPSG/0/7375']
* Promise.all(uris.map(uriproj.load)).then(projs => {
* // all projections are loaded and stored now
*
* // get the first projection
* var proj1 = projs[0]
* // or:
* var proj1 = uriproj.get(uris[0])
* })
*
*/
function load(crsUri) {
if (crsUri in projCache) {
return Promise.resolve(projCache[crsUri]);
}
var epsg = crsUriToEPSG(crsUri);
var url = 'https://epsg.io/' + epsg + '.proj4';
return fetch(url).then(function (response) {
if (!response.ok) {
throw new Error('HTTP response code: ' + response.status);
}
return response.text();
}).then(function (proj4string) {
return set(crsUri, proj4string, { reverseAxes: crsUri in needsAxesReordering });
});
}
/**
* Stores a given projection for a given URI that can then be accessed via {@link get} and {@link load}.
* If the projection is given as proj4 string and does not require axis reversal, then it is stored
* as a named projection in proj4 itself under the given URI.
*
* @param {string} crsUri The CRS URI for which to store the projection.
* @param {string|Projection} proj A proj4 string or a {@link Projection} object.
* @param {Object} [options] Options object.
* @param {boolean} [options.reverseAxes=false] If proj is a proj4 string, whether to reverse the projection axes.
* @return {Projection} The newly stored projection.
* @throws {Error} If crsUri or proj is missing, or if a PROJ.4 string cannot be parsed by proj4js.
*
* @example <caption>Storing a projection using a PROJ.4 string</caption>
* var uri = 'http://www.opengis.net/def/crs/EPSG/0/27700'
* var proj4 = '+proj=tmerc +lat_0=49 +lon_0=-2 +k=0.9996012717 +x_0=400000 +y_0=-100000 ' +
* '+ellps=airy +towgs84=446.448,-125.157,542.06,0.15,0.247,0.842,-20.489 +units=m +no_defs'
* uriproj.set(uri, proj4)
*
* @example <caption>Storing a projection using a Projection object</caption>
* var uri = 'http://www.opengis.net/def/crs/EPSG/0/27700'
* var proj = {
* forward: ([lon,lat]) => [..., ...],
* inverse: ([x,y]) => [..., ...]
* }
* uriproj.set(uri, proj)
*/
function set(crsUri, proj) {
var options = arguments.length <= 2 || arguments[2] === undefined ? {} : arguments[2];
if (!crsUri || !proj) {
throw new Error('crsUri and proj cannot be empty');
}
var projobj = void 0;
if (typeof proj === 'string') {
projobj = proj4(proj);
if (!projobj) {
throw new Error('Unsupported proj4 string: ' + proj);
}
proj4.defs(crsUri, proj);
if (options.reverseAxes) {
projobj = reverseAxes(projobj);
}
} else {
projobj = proj;
}
projCache[crsUri] = projobj;
return projobj;
}
/**
* Return the EPSG code of an OGC CRS URI of the form
* http://www.opengis.net/def/crs/EPSG/0/1234 (would return 1234).
*
* @param {string} crsUri The CRS URI for which to return the EPSG code.
* @return {string} The EPSG code.
*/
function crsUriToEPSG(uri) {
var epsg = void 0;
if (uri.indexOf(EPSG_PREFIX) === 0) {
epsg = uri.substr(EPSG_PREFIX.length);
} else {
throw new Error('Unsupported CRS URI: ' + uri);
}
return epsg;
}
/**
* Reverses projection axis order.
*
* For example, a projection with lon, lat axis order is turned into one with lat, lon order.
* This is necessary since geographic projections in proj4 can only be defined with
* lon,lat order, however some CRSs have lat,lon order (like EPSG4326).
* Incorrectly, epsg.io returns a proj4 string (with lon,lat order) even if the CRS
* has lat,lon order. This function manually flips the axis order of a given projection.
* See also `needsAxesReordering` above.
*
* @param {Projection} proj The projection whose axis order to revert.
* @return {Projection} The projection with reversed axis order.
*/
function reverseAxes(proj) {
return {
forward: function forward(pos) {
return proj.forward(pos).reverse();
},
inverse: function inverse(pos) {
return proj.inverse([pos[1], pos[0]]);
}
};
}
exports.get = get;
exports.load = load;
exports.set = set;
}((this.uriproj = this.uriproj || {}),proj4));
//# sourceMappingURL=uriproj.src.js.map