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javascriptpythonerpnextfrappe

Unable to return an image from python django (frappe framework) server and display in js doctype


I am working on FrappeFramework 'ERPNext' customization.

I need to display QR code in sales invoice and also show it in print invoice.

Current flawed solution: Right now, I fetch an encoded string from server side. On the client side, I have a QR image HTML field as such:

HTML Field screenshot

Then in js, I use a js library ‘QRious’ to render HTML into that field and the QR code is displayed.

function generateQRCode(base64) {
  var qr = new QRious({
    element: document.getElementById("qr_code"),
    size: 200,
    value: "",
  });
  var qrtext = base64;
  qr.set({
    foreground: "black",
    size: 200,
    value: qrtext,
    mime: 'image/png'
  });
}

However, when trying to print the invoice, the QR code does not appear and I cannot figure out how to hook into the print page to render the image there.

My question is:

Can I do this in a way that ERPNext will save the rendered image without me having to regenerate it every time from encoded string.

If not, how do I hook into the print page to manually render the QR code over there. (encoded string is available on print page)

P.S. I can also fetch an rgb/gray array if that helps.


Solution

  • I was able to solve this problem by making a custom print format in "Print Format List" doctype.

    I wanted a printable QR code to put on items showing QR Code, Item Code, SN

    <style>
      .print-format {
        padding: 0px;
      }
    
      @media screen {
        .print-format {
          padding: 0in;
        }
      }
    
    </style>
    
    <div style="position: relative; top:0.25cm">
      <div style="width:6.35cm;height:3.81cm;">
        <img alt='' src='https://barcode.tec-it.com/barcode.ashx?data={{ doc.item_name }} SN%3A%20{{ doc.name }}&code=QRCode&translate-esc=on' />
        <br>
        Item:{{ doc.item_code  }}
        <br>
        SN:{{ doc.serial_no  }}
      </div>
    </div>