Driverless wifi printing

stanwood

Hi, I just come back with this request, which is from my opinion maybe the only important missing feature of UT: Wireless printing.
Indeed, there are several wireless printing protocols, mostly IP, that do not require any driver. Most commun are Airprint, IPP, GCP, etc... https://wiki.debian.org/CUPSDriverlessPrinting My Ubuntu desktop uses a driverless protocol to communicate with my HP printer. By the way, I guess most apps should integrate this feature as well, which would be a hard job for devs. Are there any plans to integrate this kind of printing solution in the future?

thilov

+1

It was integrated some time ago if I remember right:
https://github.com/ubports/ubuntu-printing-app

Maybe @Flohack has more information.

stanwood

Ok thank you. Looks like the project has been started by Canonical but not continued. Strangely they prioritized it as "optional". But it's perhaps not dead anyway as I could find these repo on Github: https://github.com/ubports/ubuntu-printing-app/issues/5 and https://github.com/ubports/system-settings/blob/xenial/plugins/printing/printing.svg Hope we would start again the development, it would be nice to print out a document, mail or picture from UT

dobey

I think there's currently not enough space available to include it in the rootfs.

Flohack

Some devices have a very small cache partition which is used to update them. When we would find a way to make updates via the userdata partition this would be possible for most devices. Or find a way how to install additional debs outside of the rootfs image.

stanwood

@Flohack Thank you Flohack. Ok I understand basically the technical challenge: Allocate a temp memory range in UT image to store print datas during the spooler-service process. Nice to see that although it won’t come in the immediate future, project has not been completely abandoned. Happy Easter everyone!

Flohack

@stanwood Hello, no thats not the issue I am referring to. Once installed the print jobs will be spooled as usual in /tmp or /var/spool.

BTW its a CUPS setup, so it will already be working with a lot of printers out of the box.

What I am talking about is that during an OTA image upgrade the root file system is copied to the cache partition of the device, and that one is pretty small with Android on some devices. We cannot add new stuff to the roof filesystem without risking to break that limit so it must be done careful. Printing was announced already for end of 2018 if I remember right, but we had to remove it again.

stanwood

@Flohack Ok thank you Flohack. I do better understand technically the challenge now.

@Flohack
Could it not be provided in the form of a downloadable app, which could access documents via the content hub?

dobey

@3arn0wl said in Driverless wifi printing:

@Flohack
Could it not be provided in the form of a downloadable app, which could access documents via the content hub?

No. The "app" itself is only one small part of the printing stack. The cups packages, PPDs, etc... all need to be in the rootfs, and it runs as a system service. Also, as click packages cannot provide services and such things, trying to shove parts of this into there will only be extremely messy and hard to clean up in the future.

Thanks for that, @dobey.

stanwood

@3arn0wl So, in the meantime, we can use some workarounds. Several printers providers do offer remote printing solutions: Ex. Hewlett Packard and it's Smart print application, Canon and Brother with Google Cloud Print, etc... Some of them nevertheless need the installation of an app or software, which can not be executed with UT. Or the other way is to transfer files from UT to any cloud/drive.., than print it from another device.

stanwood

I was thinking to another way to print: And why not send the file by bluetooth using the native UT app "bluetooth transfer" to a compatible printer? Than no need any spooler service, as printer do all the work. Could that work?

dobey

@stanwood said in Driverless wifi printing:

I was thinking to another way to print: And why not send the file by bluetooth using the native UT app "bluetooth transfer" to a compatible printer? Than no need any spooler service, as printer do all the work. Could that work?

No. Bluetooth printing does not work by file transfer. Still cups would be required, to provide the print service which talks to the printer. Also, it requires extra integration to enable connecting printers from the Bluetooth settings UI.

stanwood

@dobey Ok thank you. I admit my idea was a little naive...

arubislander

Another workaround to print from your Ubuntu Touch device can be found here

stanwood

@arubislander Thank you very much for this input. So basically create a libertine container and activate softwares (such as libreoffice) to communicate to printer network. As I’m newbie I’m not sure I have the technical knowledge yet to use libertine, but will definitely keep those instructions to do it later on.