TypeError: qz.security.setCertificatePromise(...) is undefined

Question

I try to make a static simple page using HTML, JS, QZ-Tray that can print a mock data into LQ-310 printer.

I've been follow how to sign in JS from QZ-Tray wiki. However, I still have pop up message like below:

I've changed the flow from server side to client side to sign and remove this pop up, but it has no effect

NOTE:

• I successfully print the page I want to print
• Repo for the issue: Rusydy/print-qz-static

Answer 1

The project works just fine on my computer. These are the steps I ran:

1. Clone the code:

   git clone https://github.com/Rusydy/print-qz-static
   

2. Extract the certificate file used for signing messages by removing the quotes and newlines from the x509 certificate in qz-cert.js and saving it as certificate.crt.
3. Install and open QZ Tray
4. Open the Site Manager dialog in QZ Tray (QZ Tray icon, Advanced, Site Manager)
5. Drag-and-drop the certificate.crt file into the Site Manager dialog.
6. Open index.html, click "Test printer"

I did receive a JavaScript error, however it did not result in a pop-up warning dialog. The document prints first time, no pop-ups.

qz-cert.js:27 Uncaught TypeError: Cannot read properties of undefined (reading 'then')
    at qz-cert.js:27:3

This error message is fairly benign, but it's because you're using a .then(...) on your setCertificatePromise() call here. The function call setCertificatePromise() does not return a promise, so any error detection must be internal (e.g. manually throw an exception raised by fetch() or $.ajax(), etc when loading this certificate from a URL). Since you're loading the certificate from a string value, no exception handling is needed, but regardless, .then() must be removed from this file to remove the error.

In regards to the pop-up you are receiving, this is a sign that the certificate you've created hasn't been installed into QZ Tray. You may drag-and drop it into the Site Manager dialog to install it to your system (or manually by copying it to <appdir>\override.crt and restarting QZ Tray).