Opening a pdf with angular ngResource from an MVC post request - angularjs

Question

I have a POST request for a PDF document in an APIController, here's the code:
Generator pdfGenerator = new Generator();
MemoryStream ms = pdfGenerator.Generate();
var response = new HttpResponseMessage
{
StatusCode = HttpStatusCode.OK,
Content = new StreamContent(ms)
};
response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment")
{
FileName = "Tag.pdf"
};
response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");
return response;
when I send my file to angular with a GET request everything works fine and I can download the pdf using:
$window.open('my_url');
A well formed 28K pdf file is created in the download folder.
But when I changed my request to a POST the file is malformed.
var pdfGetter = $resource('my_url', {}, {
sendPDFTag: { method: 'POST', url: 'my_url', responseType: 'arraybuffer' }
});
pdfGetter.sendPDFTag(info, function(data) {
var file = new Blob([data], { type: 'application/pdf' });
var fileURL = URL.createObjectURL(file);
$window.open(fileURL);;
});
I tried using the FileSaver.js and I get a bad 1K pdf file in my download folder.
pdfGetter.sendPDFTag(info, function(data) {
var file = new Blob([data], { type: 'application/pdf' });
saveAs(file, 'Tag.pdf');
});
What could the problem be?
Thanks

Answer 1

I found the solution to my problem in this question: pdf-js-render-pdf-using-an-arraybuffer-or-blob-instead-of-url
The problem was with the ng-resource that returns a promise instead of the arraybuffer, so you need to transform the data before you process the promise.
Here is the corrected code:
var pdfGetter = $resource(myUrl, {}, {
sendPDFTag: { method: 'POST', url: myUrl + "/getPdfWithPost", responseType: 'arraybuffer',
transformResponse: function(data, headersGetter) {
// Stores the ArrayBuffer object in a property called "data"
return { data : data };
}
}
});
var pdfGetter = pdfGetter.sendPDFTag(info);
pdfGetter.$promise.then(function () {
var data = pdfGetter.data;
var file = new Blob([data], { type: 'application/pdf' });
var fileURL = URL.createObjectURL(file);
$window.open(fileURL);
});
Thank you