There are two ways to download a file where the HTTP request requires that a header be set.
The credit for the first goes to @guest271314, and credit for the second goes to @dandavis.
The first method is to use the HTML5 File API to create a temporary local file, and the second is to use base64 encoding in conjunction with a data URI.
The solution I used in my project uses the base64 encoding approach for small files, or when the File API is not available, otherwise using the the File API approach.
Solution:
var id = 123;
var req = ic.ajax.raw({
type: 'GET',
url: '/api/dowloads/'+id,
beforeSend: function (request) {
request.setRequestHeader('token', 'token for '+id);
},
processData: false
});
var maxSizeForBase64 = 1048576; //1024 * 1024
req.then(
function resolve(result) {
var str = result.response;
var anchor = $('.vcard-hyperlink');
var windowUrl = window.URL || window.webkitURL;
if (str.length > maxSizeForBase64 && typeof windowUrl.createObjectURL === 'function') {
var blob = new Blob([result.response], { type: 'text/bin' });
var url = windowUrl.createObjectURL(blob);
anchor.prop('href', url);
anchor.prop('download', id+'.bin');
anchor.get(0).click();
windowUrl.revokeObjectURL(url);
}
else {
//use base64 encoding when less than set limit or file API is not available
anchor.attr({
href: 'data:text/plain;base64,'+FormatUtils.utf8toBase64(result.response),
download: id+'.bin',
});
anchor.get(0).click();
}
}.bind(this),
function reject(err) {
console.log(err);
}
);
Note that I'm not using a raw XMLHttpRequest,
and instead using ic-ajax,
and should be quite similar to a jQuery.ajax solution.
Note also that you should substitute text/bin and .bin with whatever corresponds to the file type being downloaded.
The implementation of FormatUtils.utf8toBase64
can be found here