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@qetr1ck-op
Created February 17, 2016 10:00
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(function(self) {
'use strict';
if (self.fetch) {
return
}
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
}
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)
}
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)
}
var support = {
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 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 (!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)
}
}
}
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.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);
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