Re: [cups-devel] cups-devel Digest, Vol 27, Issue 3

"tong@hue" <[email protected]> Fri, 05 Feb 2016 18:07:37 +0800
Newsgroups	gmane.comp.printing.cups.devel
Message-ID	<CAO6GHWA-=Ot3wOVNc15wBMUL0LPHREmTgpNhBDPARzEnXxTi-A@mail.gmail.com>
Most POS printers could receive either raster data or ESC/POS commands but
for my application, I will be working primarily with esc/pos data.

I stumbled on tea4cups and from what I have learned, offers print data
manipulation
using the backend filter.

Would that be sufficient to handle step l & IV?

As for step II & III, I am planning to use either Python ESC/POS(
https://github.com/python-escpos/python-escpos) or ESC/POS PHP library (
https://github.com/mike42/escpos-php) to create and append the QR code.

Thanks!

TG



On 5 February 2016 at 04:00, <[email protected]> wrote:

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> Today's Topics:
>
>    1. Re: [UNKN] STR #4764: allow setting of default user       name from
>       per instance options (Vincent Danjean)
>    2. Re: [UNKN] STR #4764: allow setting of default user       name from
>       per instance options (Vincent Danjean)
>    3. [UNKN] STR #4767: Possible nonconformance of      'hold-new-jobs'
>       to RFC3998/3.3.1 (Arney)
>    4. [UNKN] STR #4768: Brazilian Portuguese (pt_BR)    translation
>       for CUPS (Rafael Fontenelle)
>    5. Capture raw print data,   append QR code before sending to
>       printer (CK TONG)
>    6. Re: [UNKN] STR #4764: allow setting of default user       name from
>       per instance options (Michael Sweet)
>    7. Re: [UNKN] STR #4764: allow setting of default user       name from
>       per instance options (Vincent Danjean)
>    8. Re: Capture raw print data,       append QR code before sending to
>       printer (Helge Blischke)
>
>
> ----------------------------------------------------------------------
>
> Message: 1
> Date: Thu,  4 Feb 2016 03:43:18 -0800 (PST)
> From: Vincent Danjean <[email protected]>
> To: [email protected]
> Cc: [email protected], [email protected]
> Subject: Re: [cups-devel] [UNKN] STR #4764: allow setting of default
>         user    name from per instance options
> Message-ID: <20160204114318.1587814706E-NXuN9tI6zXJg9hUCZPvPmw@public.gmane.org>
> Content-Type: text/plain
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA512
>
> DO NOT REPLY TO THIS MESSAGE.  INSTEAD, POST ANY RESPONSES TO THE LINK
> BELOW.
>
> [STR Unresolved]
>
> Argh. I really do not understand to design to allow to choose a username
> system-wide (/etc/client.conf) or account-wide ($HOME/.cups/client.conf)
> but not per queue, unless you do not consider the use-case of a computer
> (laptop) that connect to different environments.
>
> I tried to dig into the code, but I did not see any easy way to turn
> arround this problem. In my case, the backend is lpd that use the name from
> the second parameter of its invocation. As the backend is launched by the
> cups scheduler at the same time as the filters (connected by pipes), there
> is no way a filter can 'update' the login name for the lpd backend. The
> only 'trick' I can think of is that a filter add the modified username
> (taken from a cups option and/or a ppd field) to its output and that a
> wrapper lpd backend first read the name from the job that comes and invoke
> the real backend with the user name modified...
>
> I will perhaps try that if I fond the time to do it. But it will be
> specific to my usecase, not something that can be integrated upstream.
>
> Link: https://www.cups.org/str.php?L4764
> Version: 2.1.2
> Fix Version: None
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>
>
> ------------------------------
>
> Message: 2
> Date: Thu,  4 Feb 2016 04:25:43 -0800 (PST)
> From: Vincent Danjean <[email protected]>
> To: [email protected]
> Cc: [email protected], [email protected]
> Subject: Re: [cups-devel] [UNKN] STR #4764: allow setting of default
>         user    name from per instance options
> Message-ID: <20160204122543.0D44E140196-NXuN9tI6zXJg9hUCZPvPmw@public.gmane.org>
> Content-Type: text/plain
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA512
>
> DO NOT REPLY TO THIS MESSAGE.  INSTEAD, POST ANY RESPONSES TO THE LINK
> BELOW.
>
> [STR Unresolved]
>
> Still the 'Unable to save file to STR: Browser-supplied MIME media type
> does not match filename extension.'.
> Trying as a tar.gz...
>
> Link: https://www.cups.org/str.php?L4764
> Version: 2.1.2
> Fix Version: None
> Attachment: https://www.cups.org/strfiles.php/3603/username-wrapper.tar.gz
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>
> ------------------------------
>
> Message: 3
> Date: Thu,  4 Feb 2016 05:07:15 -0800 (PST)
> From: Arney <[email protected]>
> To: [email protected]
> Subject: [cups-devel] [UNKN] STR #4767: Possible nonconformance of
>         'hold-new-jobs' to RFC3998/3.3.1
> Message-ID: <20160204130715.1632C141227-NXuN9tI6zXJg9hUCZPvPmw@public.gmane.org>
> Content-Type: text/plain
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA512
>
> DO NOT REPLY TO THIS MESSAGE.  INSTEAD, POST ANY RESPONSES TO THE LINK
> BELOW.
>
> [STR New]
>
> Given the scenario
>
> sudo lpadmin -p TestPrinter -m drv:///sample.drv/generic.ppd
> sudo lpadmin -d TestPrinter
> sudo cupsaccept TestPrinter
> lp sometext.txt
> lp sometext.txt
> lp sometext.txt
> sudo cupsdisable --hold TestPrinter
> lp sometext.txt
> lp sometext.txt
> lp sometext.txt
> sudo cupsenable TestPrinter
>
> I would expect the first three pending jobs to start printing while the
> later three jobs should remain pending-held.
>
> Actual behavior: All jobs remain queued until the queue gets released.
>
> Tested on:
> - - Ubuntu 14.04 (CUPS 1.7.4)
> - - Ubuntu 15.10 (CUPS 2.0.2)
> - - Centos7 (CUPS 1.6.3)
>
> Link: https://www.cups.org/str.php?L4767
> Version: 2.0.2
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>
>
> ------------------------------
>
> Message: 4
> Date: Thu,  4 Feb 2016 05:26:00 -0800 (PST)
> From: Rafael Fontenelle <[email protected]>
> To: [email protected]
> Subject: [cups-devel] [UNKN] STR #4768: Brazilian Portuguese (pt_BR)
>         translation for CUPS
> Message-ID: <20160204132600.08C68140196-NXuN9tI6zXJg9hUCZPvPmw@public.gmane.org>
> Content-Type: text/plain
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA512
>
> DO NOT REPLY TO THIS MESSAGE.  INSTEAD, POST ANY RESPONSES TO THE LINK
> BELOW.
>
> [STR New]
>
> The attached tarball contains desktop file, index.html.in, templates and
> PO
> file translation for Brazilian Portuguese. Translation is ready for version
> 2.1.2.
>
> Link: https://www.cups.org/str.php?L4768
> Version: 2.1.2
> Attachment: https://www.cups.org/strfiles.php/3604/pt_BR.tar.gz
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>
>
> ------------------------------
>
> Message: 5
> Date: Thu, 4 Feb 2016 17:09:33 +0800
> From: CK TONG <mail-/OGFVUI/Gc/[email protected]>
> To: [email protected]
> Subject: [cups-devel] Capture raw print data,   append QR code before
>         sending to printer
> Message-ID:
>         <
> CAO6GHWCxoVHGPBKHqgdsyOVKC94rhJLfi4DWSafq9RQkKTJFOQ-JsoAwUIsXosN+BqQ9rBEUg@public.gmane.org>
> Content-Type: text/plain; charset=UTF-8
>
> I am trying to intercept raw print data stream from a POS system, modify it
> before sending it to a networked Epson thermal receipt printer as described
> below:
>
>
> i) Intercept print data,
>
> ii) use the data to encode a QR code,
>
> iii) append it to the captured data,
>
> iv) send to printer
>
>
> I have limited knowledge on linux and CUPS. Appreciate if someone could
> direct me to relevant resource for further research.
>
>
> Thanks in advance!
>
>
> TG
>
>
> ------------------------------
>
> Message: 6
> Date: Thu,  4 Feb 2016 07:16:04 -0800 (PST)
> From: Michael Sweet <[email protected]>
> To: [email protected]
> Cc: [email protected], [email protected]
> Subject: Re: [cups-devel] [UNKN] STR #4764: allow setting of default
>         user    name from per instance options
> Message-ID: <20160204151604.E813D141203-NXuN9tI6zXJg9hUCZPvPmw@public.gmane.org>
> Content-Type: text/plain
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA512
>
> DO NOT REPLY TO THIS MESSAGE.  INSTEAD, POST ANY RESPONSES TO THE LINK
> BELOW.
>
> [STR Unresolved]
>
> If you use a modern network printing protocol (i.e. IPP) then the username
> can be requested and authenticated by the server.  LPD is "print and pray"
> and has no way to tell the client it needs a different user or to
> authenticate the user that is provided.
>
> Link: https://www.cups.org/str.php?L4764
> Version: 2.1.2
> Fix Version: None
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>
>
> ------------------------------
>
> Message: 7
> Date: Thu,  4 Feb 2016 07:50:32 -0800 (PST)
> From: Vincent Danjean <[email protected]>
> To: [email protected]
> Cc: [email protected], [email protected]
> Subject: Re: [cups-devel] [UNKN] STR #4764: allow setting of default
>         user    name from per instance options
> Message-ID: <20160204155032.591A5140196-NXuN9tI6zXJg9hUCZPvPmw@public.gmane.org>
> Content-Type: text/plain
>
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA512
>
> DO NOT REPLY TO THIS MESSAGE.  INSTEAD, POST ANY RESPONSES TO THE LINK
> BELOW.
>
> [STR Unresolved]
>
> I've lots of constraints due to the fact that I cannot configure/manage the
> main printer server. The main printer server can be reached by either lpd
> or ipp (both services provided by a windows server that allows to print the
> job on any of all printers of the building after authentification on the
> printer)
>   So, to get its print, a user must submit its job with the username he
> will be able to authentificate itself on the printer (but the main print
> server do not require authentification at submission time, only at printing
> time on the printers themselves).
>
>   As the building has several subnetworks and DNS-SD is not used, we
> installed on our subnet a local cups server that relay jobs to the main
> server (so no local configuration on client is required to be able to
> print, avahi being used to propose the printer).
>   But, sometimes, user do not have the same login on their laptop and on
> the print server.
>   So, to avoid the needed to write config files (and to allow to have
> different username for different printers as we have the same kind of setup
> in another building with different logins), I managed to write a wrapper
> against the lpd backend (cf my previous message). I suppose (but I did not
> test) that the same trick could possibly be used by the ipp backend (I'm
> not sure here as the ipp backend is probably more complex as it is
> bidirectionnal).
>
>   That said, sometimes, on the middle (local) cups server, I detect the
> submitted user name is wrong. I would like to report this error to the user
> (so the error detection occurs *before* the lpd protocol is used). For now,
> I did not find how to do it. The job is just quietly discarded. The user do
> not see in a job list for example that its job have been discarded. It is
> displayed as if it has been sent to the main print server.
>   I was asking if there is a correct way for a backend or a filter to
> report back to the user that its job has been discarded instead of being
> sent to the printer.
>
> Link: https://www.cups.org/str.php?L4764
> Version: 2.1.2
> Fix Version: None
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>
>
> ------------------------------
>
> Message: 8
> Date: Thu, 4 Feb 2016 20:40:15 +0100
> From: Helge Blischke <helgeblischke-S0/[email protected]>
> To: "The CUPS developer list." <[email protected]>
> Subject: Re: [cups-devel] Capture raw print data,       append QR code
>         before sending to printer
> Message-ID: <1056905C-5591-4596-B510-220C4789FADA-S0/[email protected]>
> Content-Type: text/plain; charset=us-ascii
>
>
> > Am 04.02.2016 um 10:09 schrieb CK TONG <mail-/OGFVUI/Gc/[email protected]>:
> >
> > I am trying to intercept raw print data stream from a POS system, modify
> it
> > before sending it to a networked Epson thermal receipt printer as
> described
> > below:
> >
> >
> > i) Intercept print data,
> >
> > ii) use the data to encode a QR code,
> >
> > iii) append it to the captured data,
> >
> > iv) send to printer
> >
> >
> > I have limited knowledge on linux and CUPS. Appreciate if someone could
> > direct me to relevant resource for further research.
> >
> >
> > Thanks in advance!
> >
> >
> > TG
>
> First, we must know what kind of data you get from your POS system in
> order to
> think about how to accomplish your items II and III.
>
> Helge
>
>
>
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> End of cups-devel Digest, Vol 27, Issue 3
> *****************************************
>