Print PDF directly from JavaScript

Based on comments below, it no longer works in modern browsers
This question demonstrates an approach that might be helpful to you: Silent print an embedded PDF

It uses the <embed> tag to embed the PDF in the document:

<embed
    type="application/pdf"
    src="path_to_pdf_document.pdf"
    id="pdfDocument"
    width="100%"
    height="100%" />

Then you call the .print() method on the element in Javascript when the PDF is loaded:

function printDocument(documentId) {
    var doc = document.getElementById(documentId);

    //Wait until PDF is ready to print    
    if (typeof doc.print === 'undefined') {    
        setTimeout(function(){printDocument(documentId);}, 1000);
    } else {
        doc.print();
    }
}

You could place the embed in a hidden iframe and print it from there, giving you a seamless experience.

Here is a function to print a PDF from an iframe.

You just need to pass the URL of the PDF to the function. It will create an iframe and trigger print once the PDF is load.

Note that the function doesn't destroy the iframe. Instead, it reuses it each time the function is call. It's hard to destroy the iframe because it is needed until the printing is done, and the print method doesn't has callback support (as far as I know).

printPdf = function (url) {
  var iframe = this._printIframe;
  if (!this._printIframe) {
    iframe = this._printIframe = document.createElement('iframe');
    document.body.appendChild(iframe);

    iframe.style.display = 'none';
    iframe.onload = function() {
      setTimeout(function() {
        iframe.focus();
        iframe.contentWindow.print();
      }, 1);
    };
  }

  iframe.src = url;
}

You can use Print.js (npm install print-js). It's 128kB unpacked and you can find the docs at http://printjs.crabbly.com/.

It doesn't print on IE though, in those cases you'll have to download the PDF instead.

$http({
    url: "",
    method: "GET",
    headers: {
        "Content-type": "application/pdf"
    },
    responseType: "arraybuffer"
}).success(function (data, status, headers, config) {
    var pdfFile = new Blob([data], {
        type: "application/pdf"
    });
    var pdfUrl = URL.createObjectURL(pdfFile);
    //window.open(pdfUrl);
    printJS(pdfUrl);
    //var printwWindow = $window.open(pdfUrl);
    //printwWindow.print();
}).error(function (data, status, headers, config) {
    alert("Sorry, something went wrong")
});

https://github.com/mozilla/pdf.js/

for a live demo http://mozilla.github.io/pdf.js/

it's probably what you want, but I can't see the point of this since modern browsers include such functionality, also it will run terribly slow on low-powered devices like mobile devices that, by the way, have their own optimized plugins and apps.

I used this function to download pdf stream from server.

function printPdf(url) {
        var iframe = document.createElement('iframe');
        // iframe.id = 'pdfIframe'
        iframe.className='pdfIframe'
        document.body.appendChild(iframe);
        iframe.style.display = 'none';
        iframe.onload = function () {
            setTimeout(function () {
                iframe.focus();
                iframe.contentWindow.print();
                URL.revokeObjectURL(url)
                // document.body.removeChild(iframe)
            }, 1);
        };
        iframe.src = url;
        // URL.revokeObjectURL(url)
    }