cups-queue-listener

Enables node scripts to listen to CUPS specific events, like succesfull prints, errored prints and queue length.

usage

The exported value from this module is an eventEmitter. You can add listeners to it to be notified of the following events print-error and print-success.
When you add some file to the CUPS queue (for instance by $ lp filename.pdf or by using the cups-print module), you will get the job id and the destination it is queued for.
Emit an print-queued event (see example below) on the cups-queue-listener with that id and destination to enable it sending the following events:

• queue-update, with the folling data; queue: the number of items currently in the queue, queued: the number of items in the queue which are not yet printed, printed: the number of printed items, destination: the printer for which these items are queued.
• queue-almost-empty, with data; destination: the destination for which the queue is almost empty (5 items left).
• all-printed, with data; destination: the destination for which the queue is all printed.

These events are also emitted as destination specific events. they have the same data as above but lack the destination property.

• queue-update-${destination}
• queue-almost-empty-${destination}
• all-printed-${destination}

queueListener.on('queue-update-somePrinterName', (data) => {
  console.log(data);
});

examples

import queueListener from 'cups-queue-listener';
import print from 'cups-print';


queListener
  .on("print-error", (data) => {
     console.log("error printing", data);
   })
   .on("print-success", (data) => {
     console.log("\\o/", data);
   })
   .on("queue-update", (data) => {
     console.log(data);
   })
   .on("queue-almost-empty", ({ destination }) => {
     console.log(`${destination} queue is almost empty`);
   });


// do some print action
const { id, destination } = print('some-pdf-File.pdf');
queueListener.emit('print-queued', { id, destination });