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Cut down for ES6 and ESLint compatibility
// download.js v4.21, by dandavis; 2008-2018. [MIT] see http://danml.com/download.html for tests/usage
// v1 landed a FF+Chrome compatible way of downloading strings to local un-named files, upgraded to use a hidden frame and optional mime
// v2 added named files via a[download], msSaveBlob, IE (10+) support, and window.URL support for larger+faster saves than dataURLs
// v3 added dataURL and Blob Input, bind-toggle arity, and legacy dataURL fallback was improved with force-download mime and base64 support. 3.1 improved safari handling.
// v4 adds AMD/UMD, commonJS, and plain browser support
// v4.1 adds url download capability via solo URL argument (same domain/CORS only)
// v4.2 adds semantic variable names, long (over 2MB) dataURL support, and hidden by default temp anchors
// https://github.com/rndme/download
export default function download (data, strFileName, strMimeType) {
const Blob = window.Blob
const XMLHttpRequest = window.XMLHttpRequest
var self = window // this script is only for browsers anyway...
var defaultMime = 'application/octet-stream' // this default mime also triggers iframe downloads
var mimeType = strMimeType || defaultMime
var payload = data
var url = !strFileName && !strMimeType && payload
var anchor = document.createElement('a')
var toString = function (a) {
return String(a)
}
var MyBlob = self.Blob || self.MozBlob || self.WebKitBlob || toString
var fileName = strFileName || 'download'
var blob
var reader
MyBlob = MyBlob.call ? MyBlob.bind(self) : Blob
if (String(this) === 'true') {
// reverse arguments, allowing download.bind(true, "text/xml", "export.xml") to act as a callback
payload = [payload, mimeType]
mimeType = payload[0]
payload = payload[1]
}
if (url && url.length < 2048) {
// if no filename and no mime, assume a url was passed as the only argument
fileName = url
.split('/')
.pop()
.split('?')[0]
anchor.href = url // assign href prop to temp anchor
if (anchor.href.indexOf(url) !== -1) {
// if the browser determines that it's a potentially valid url path:
var ajax = new XMLHttpRequest()
ajax.open('GET', url, true)
ajax.responseType = 'blob'
ajax.onload = function (e) {
download(e.target.response, fileName, defaultMime)
}
setTimeout(function () {
ajax.send()
}, 0) // allows setting custom ajax headers using the return:
return ajax
} // end if valid url?
} // end if url?
// go ahead and download dataURLs right away
if (/^data:([\w+-]+\/[\w+.-]+)?[,;]/.test(payload)) {
if (payload.length > 1024 * 1024 * 1.999 && MyBlob !== toString) {
payload = dataUrlToBlob(payload)
mimeType = payload.type || defaultMime
} else {
return navigator.msSaveBlob // IE10 can't do a[download], only Blobs:
? navigator.msSaveBlob(dataUrlToBlob(payload), fileName)
: saver(payload) // everyone else can save dataURLs un-processed
}
} else {
// not data url, is it a string with special needs?
if (/([\x80-\xff])/.test(payload)) {
var i = 0
var tempUiArr = new Uint8Array(payload.length)
var mx = tempUiArr.length
for (i; i < mx; ++i) tempUiArr[i] = payload.charCodeAt(i)
payload = new MyBlob([tempUiArr], { type: mimeType })
}
}
blob = payload instanceof MyBlob ? payload : new MyBlob([payload], { type: mimeType })
function dataUrlToBlob (strUrl) {
var parts = strUrl.split(/[:;,]/)
var type = parts[1]
var indexDecoder = strUrl.indexOf('charset') > 0 ? 3 : 2
var decoder = parts[indexDecoder] === 'base64' ? window.atob : decodeURIComponent
var binData = decoder(parts.pop())
var mx = binData.length
var i = 0
var uiArr = new Uint8Array(mx)
for (i; i < mx; ++i) uiArr[i] = binData.charCodeAt(i)
return new MyBlob([uiArr], { type: type })
}
function saver (url, winMode) {
if ('download' in anchor) {
// html5 A[download]
anchor.href = url
anchor.setAttribute('download', fileName)
anchor.className = 'download-js-link'
anchor.innerHTML = 'downloading...'
anchor.style.display = 'none'
var listener = anchor.addEventListener('click', function (e) {
e.stopPropagation()
this.removeEventListener('click', listener)
})
document.body.appendChild(anchor)
setTimeout(function () {
anchor.click()
document.body.removeChild(anchor)
if (winMode === true) {
setTimeout(function () {
self.URL.revokeObjectURL(anchor.href)
}, 250)
}
}, 66)
return true
}
// handle non-a[download] safari as best we can:
if (/(Version)\/(\d+)\.(\d+)(?:\.(\d+))?.*Safari\//.test(navigator.userAgent)) {
if (/^data:/.test(url)) url = 'data:' + url.replace(/^data:([\w/\-+]+)/, defaultMime)
if (!window.open(url)) {
// popup blocked, offer direct download:
if (window.confirm('Displaying New Document\n\nUse Save As... to download, then click back to return to this page.')) {
window.location.href = url
}
}
return true
}
// do iframe dataURL download (old ch+FF):
var f = document.createElement('iframe')
document.body.appendChild(f)
if (!winMode && /^data:/.test(url)) {
// force a mime that will download:
url = 'data:' + url.replace(/^data:([\w/\-+]+)/, defaultMime)
}
f.src = url
setTimeout(function () {
document.body.removeChild(f)
}, 333)
} // end saver
if (navigator.msSaveBlob) {
// IE10+ : (has Blob, but not a[download] or URL)
return navigator.msSaveBlob(blob, fileName)
}
if (self.URL) {
// simple fast and modern way using Blob and URL:
saver(self.URL.createObjectURL(blob), true)
} else {
// handle non-Blob()+non-URL browsers:
if (typeof blob === 'string' || blob.constructor === toString) {
try {
return saver('data:' + mimeType + ';base64,' + self.btoa(blob))
} catch (y) {
return saver('data:' + mimeType + ',' + encodeURIComponent(blob))
}
}
// Blob but not URL support:
reader = new window.FileReader()
reader.onload = function (e) {
saver(this.result)
}
reader.readAsDataURL(blob)
}
return true
} /* end download() */
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