[javascript] PDF Blob - Pop up window not showing content

I have been working on this problem for the last few days. With no luck on trying to display the stream on <embed src> tag, I just tried to display it on a new window.

The new window shows PDF controls only )

Any idea why the content of the pdf is not showing?

CODE:

$http.post('/fetchBlobURL',{myParams}).success(function (data) {
    var file = new Blob([data], {type: 'application/pdf'});
    var fileURL = URL.createObjectURL(file);
    window.open(fileURL);
});

If you set { responseType: 'blob' }, no need to create Blob on your own. You can simply create url based with response content:

$http({
    url: "...",
    method: "POST",
    responseType: "blob"
}).then(function(response) {
    var fileURL = URL.createObjectURL(response.data);
    window.open(fileURL);
});

// I used this code with the fpdf library.
// Este código lo usé con la libreria fpdf.

var datas = json1;
var xhr = new XMLHttpRequest();
xhr.open("POST", "carpeta/archivo.php");
xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xhr.responseType = "blob";
xhr.onload = function () {
    if (this.status === 200) {
        var blob = new Blob([xhr.response], {type: 'application/pdf'});
        const url = window.URL.createObjectURL(blob);
        window.open(url,"_blank");
        setTimeout(function () {
            // For Firefox it is necessary to delay revoking the ObjectURL
            window.URL.revokeObjectURL(datas)
                , 100
        })
    }
};
xhr.send("men="+datas);

I ended up just downloading my pdf using below code

function downloadPdfDocument(fileName){

var req = new XMLHttpRequest();
req.open("POST", "/pdf/" + fileName, true);
req.responseType = "blob";
fileName += "_" + new Date() + ".pdf";

req.onload = function (event) {

    var blob = req.response;

    //for IE
    if (window.navigator && window.navigator.msSaveOrOpenBlob) {
        window.navigator.msSaveOrOpenBlob(blob, fileName);
    } else {

        var link = document.createElement('a');
        link.href = window.URL.createObjectURL(blob);
        link.download = fileName;
        link.click();
    }
};

req.send();

}

I have been struggling for days finally the solution which worked for me is given below. I had to make the window.print() for PDF in new window needs to work.

 var xhr = new XMLHttpRequest();
      xhr.open('GET', pdfUrl, true);
      xhr.responseType = 'blob';

      xhr.onload = function(e) {
        if (this['status'] == 200) {          
          var blob = new Blob([this['response']], {type: 'application/pdf'});
          var url = URL.createObjectURL(blob);
          var printWindow = window.open(url, '', 'width=800,height=500');
          printWindow.print()
        }
      };

      xhr.send();

Some notes on loading PDF & printing in a new window.

• Loading pdf in a new window via an iframe will work, but the print will not work if url is an external url.
• Browser pop ups must be allowed, then only it will work.
• If you try to load iframe from external url and try window.print() you will get empty print or elements which excludes iframe. But you can trigger print manually, which will work.

I use AngularJS v1.3.4

HTML:

<button ng-click="downloadPdf()" class="btn btn-primary">download PDF</button>

JS controller:

'use strict';
angular.module('xxxxxxxxApp')
    .controller('MathController', function ($scope, MathServicePDF) {
        $scope.downloadPdf = function () {
            var fileName = "test.pdf";
            var a = document.createElement("a");
            document.body.appendChild(a);
            MathServicePDF.downloadPdf().then(function (result) {
                var file = new Blob([result.data], {type: 'application/pdf'});
                var fileURL = window.URL.createObjectURL(file);
                a.href = fileURL;
                a.download = fileName;
                a.click();
            });
        };
});

JS services:

angular.module('xxxxxxxxApp')
    .factory('MathServicePDF', function ($http) {
        return {
            downloadPdf: function () {
            return $http.get('api/downloadPDF', { responseType: 'arraybuffer' }).then(function (response) {
                return response;
            });
        }
    };
});

Java REST Web Services - Spring MVC:

@RequestMapping(value = "/downloadPDF", method = RequestMethod.GET, produces = "application/pdf")
    public ResponseEntity<byte[]> getPDF() {
        FileInputStream fileStream;
        try {
            fileStream = new FileInputStream(new File("C:\\xxxxx\\xxxxxx\\test.pdf"));
            byte[] contents = IOUtils.toByteArray(fileStream);
            HttpHeaders headers = new HttpHeaders();
            headers.setContentType(MediaType.parseMediaType("application/pdf"));
            String filename = "test.pdf";
            headers.setContentDispositionFormData(filename, filename);
            ResponseEntity<byte[]> response = new ResponseEntity<byte[]>(contents, headers, HttpStatus.OK);
            return response;
        } catch (FileNotFoundException e) {
           System.err.println(e);
        } catch (IOException e) {
            System.err.println(e);
        }
        return null;
    }

problem is, it is not converted to proper format. Use function "printPreview(binaryPDFData)" to get print preview dialog of binary pdf data. you can comment script part if you don't want print dialog open.

printPreview = (data, type = 'application/pdf') => {
    let blob = null;
    blob = this.b64toBlob(data, type);
    const blobURL = URL.createObjectURL(blob);
    const theWindow = window.open(blobURL);
    const theDoc = theWindow.document;
    const theScript = document.createElement('script');
    function injectThis() {
        window.print();
    }
    theScript.innerHTML = `window.onload = ${injectThis.toString()};`;
    theDoc.body.appendChild(theScript);
};

b64toBlob = (content, contentType) => {
    contentType = contentType || '';
    const sliceSize = 512;
     // method which converts base64 to binary
    const byteCharacters = window.atob(content); 

    const byteArrays = [];
    for (let offset = 0; offset < byteCharacters.length; offset += sliceSize) {
        const slice = byteCharacters.slice(offset, offset + sliceSize);
        const byteNumbers = new Array(slice.length);
        for (let i = 0; i < slice.length; i++) {
            byteNumbers[i] = slice.charCodeAt(i);
        }
        const byteArray = new Uint8Array(byteNumbers);
        byteArrays.push(byteArray);
    }
    const blob = new Blob(byteArrays, {
        type: contentType
    }); // statement which creates the blob
    return blob;
};