Bug#899259: closed by Brian Potkin (Re: Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity)

2018-06-25 Thread Francesco Poli
On Thu, 21 Jun 2018 22:07:50 +0100 Brian Potkin wrote:

[...]
> Thank you for the confirmation that "PreserveJobHistory No" works for
> you. This is a win in my book, irrespective of the inticacies involved
> in socket activation. You seem happy with the outcome, so let us close
> this this report and see what the future brings.

That's fine for the time being.

> 
> My appreciation for your co-operation,

Thanks to you for helping me to find a working setup!
Bye.

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. Francesco Poli .
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Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-06-21 Thread Francesco Poli
On Wed, 20 Jun 2018 15:33:20 +0100 Brian Potkin wrote:

[...]
> Looking at the debug2 error log lead me to putting
> 
>   PreserveJobHistory No
> 
> in cupsd.conf. This gives reliable and consistent socket activation
> and timing out. How about for you?

Thanks for the suggestion.

Now I am trying with the following configuration:

  $ grep -v '^#' /etc/cups/cupsd.conf | head -n 18
  
  LogLevel warn
  PageLogFormat
  
  MaxLogSize 0
  
  Listen localhost:631
  Listen /var/run/cups/cups.sock
  IdleExitTimeout 60
  PreserveJobHistory No
  
  Browsing No
  BrowseLocalProtocols dnssd
  
  DefaultAuthType Basic
  
  WebInterface No


Judging from the few tests that I could perform (without wiping out the
whole Amazon rainforest, print test after print test!), socket
activation seems to work as intended.
I hope it will go on working correctly...



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. Francesco Poli .
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Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-06-20 Thread Brian Potkin
On Wed 20 Jun 2018 at 00:31:19 +0200, Francesco Poli wrote:

> On Tue, 19 Jun 2018 14:25:07 +0100 Brian Potkin wrote:
> 
> [...]
> >   A temporary workaround is to run:
> > 
> > cupsctl Browsing=No
> > 
> >   to restore the CUPS default setting.
> > 
> > How do you go on with that, Francesco?
> 
> I can try, but I already have:
> 
>   $ grep Browsing /etc/cups/cupsd.conf 
>   Browsing Off

I also tried with this but it didn't give me anything that I would
want to recommend. Indeed, socket deacativation took place at the
first printing attempt but thereafter the timeout behaviour was
inconsistent. However, IMO, the suggestion and the committed code
from upstream are the best we are going to get for now.

Looking at the debug2 error log lead me to putting

  PreserveJobHistory No

in cupsd.conf. This gives reliable and consistent socket activation
and timing out. How about for you?

Cheers,

Brian.



Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-06-20 Thread Brian Potkin
On Wed 20 Jun 2018 at 00:31:19 +0200, Francesco Poli wrote:

> On Tue, 19 Jun 2018 14:25:07 +0100 Brian Potkin wrote:
> 
> [...]
> >   A temporary workaround is to run:
> > 
> > cupsctl Browsing=No
> > 
> >   to restore the CUPS default setting.
> > 
> > How do you go on with that, Francesco?
> 
> I can try, but I already have:
> 
>   $ grep Browsing /etc/cups/cupsd.conf 
>   Browsing Off
> 
> Isn't that enough to disable browsing ?!?
> I have always thought it was...
> Has something changed recently?
> 
> Wait, I see that
> 
>   $ /usr/sbin/cupsctl
>   _debug_logging=0
>   _remote_admin=0
>   _remote_any=0
>   _share_printers=0
>   _user_cancel_any=0
>   BrowseLocalProtocols=dnssd
>   DefaultAuthType=Basic
>   IdleExitTimeout=60
>   JobPrivateAccess=default
>   JobPrivateValues=default
>   MaxLogSize=0
>   PageLogFormat=
>   SubscriptionPrivateAccess=default
>   SubscriptionPrivateValues=default
>   WebInterface=No
> 
> does not include any value for Browsing ...

My output is the same as this.
 
> Does this mean that "Off" is not a valid value for Browsing and that
> cupsd simply ignores invalid values?!? without complaining at all?!?

"Browsing Off", "Browsing No" and "Browsing 0" are all equivalent.
A value other than these (xxx, say) is interpreted as "Yes".

Cheers,

Brian.



Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-06-19 Thread Francesco Poli
On Tue, 19 Jun 2018 14:25:07 +0100 Brian Potkin wrote:

[...]
>   A temporary workaround is to run:
> 
> cupsctl Browsing=No
> 
>   to restore the CUPS default setting.
> 
> How do you go on with that, Francesco?

I can try, but I already have:

  $ grep Browsing /etc/cups/cupsd.conf 
  Browsing Off

Isn't that enough to disable browsing ?!?
I have always thought it was...
Has something changed recently?

Wait, I see that

  $ /usr/sbin/cupsctl
  _debug_logging=0
  _remote_admin=0
  _remote_any=0
  _share_printers=0
  _user_cancel_any=0
  BrowseLocalProtocols=dnssd
  DefaultAuthType=Basic
  IdleExitTimeout=60
  JobPrivateAccess=default
  JobPrivateValues=default
  MaxLogSize=0
  PageLogFormat=
  SubscriptionPrivateAccess=default
  SubscriptionPrivateValues=default
  WebInterface=No

does not include any value for Browsing ...

Does this mean that "Off" is not a valid value for Browsing and that
cupsd simply ignores invalid values?!? without complaining at all?!?



-- 
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 There's not a second to spare! To the laboratory!
. Francesco Poli .
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Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-06-19 Thread Brian Potkin
Quouting from

https://github.com/apple/cups/issues/5319:

  OK, near as I can guess the issue is that Browsing (sharing) is
  enable by default in Debian (sigh...) which means that the idle
  exit timeout will not kick in as soon as there is a print queue
  (== hey we are doing printer sharing), even if that queue is not
  being shared itself (printer sharing has both a global on/off
  switch as well as the per-printer switch...)

  Right now the code for idle exit isn't smart enough to know the
  difference between printers that are shared and printers that are
  not shared. Will look some potential changes that don't cause a
  performance regression...

Followed by:

  A temporary workaround is to run:

cupsctl Browsing=No

  to restore the CUPS default setting.

How do you go on with that, Francesco?

Cheers,

Brian.



Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-05-25 Thread Francesco Poli
On Fri, 25 May 2018 23:42:09 +0100 Brian Potkin wrote:

[...]
> I have reported this bug upstream.

Thanks a lot!



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 There's not a second to spare! To the laboratory!
. Francesco Poli .
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Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-05-25 Thread Brian Potkin
tags 899259 upstream
forwarded 899259 https://github.com/apple/cups/issues/5319
thanks



On Fri 25 May 2018 at 23:38:44 +0200, Francesco Poli wrote:

> On Fri, 25 May 2018 20:56:18 +0100 Brian Potkin wrote:
> 
> [...]
> > Did using socket activation on stretch ever work for you when printing?
> 
> Well, as I said in , socket
> activation used to work in versions up to cups-daemon/2.2.6-5,
> if I recall correctly...

I have reported this bug upstream.

Cheers,

Brian.



Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-05-25 Thread Francesco Poli
On Fri, 25 May 2018 20:56:18 +0100 Brian Potkin wrote:

[...]
> Did using socket activation on stretch ever work for you when printing?

Well, as I said in , socket
activation used to work in versions up to cups-daemon/2.2.6-5,
if I recall correctly...


-- 
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 There's not a second to spare! To the laboratory!
. Francesco Poli .
 GnuPG key fpr == CA01 1147 9CD2 EFDF FB82  3925 3E1C 27E1 1F69 BFFE


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Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-05-25 Thread Yves-Alexis Perez
-BEGIN PGP SIGNED MESSAGE-
Hash: SHA256

On Fri, 2018-05-25 at 19:23 +0100, Brian Potkin wrote:
> Yves-Alexis Perez (cc'ed) has an interest in socket activation working. I
> wonder whether he observes the behaviour described in b) when printing?
> Yves-Alexis?

Hi,

it's been a while since I really looked into this, and I *think* socket
activation works, but I don't use lpq/lpr. I use system-config-printer, which
seems to activate cups just fine, which then stops after one minute.

Basic config is:

egrep -v '^#|^$' /etc/cups/cupsd.conf
LogLevel warn
MaxLogSize 0
Listen /run/cups/cups.sock
Browsing On
BrowseLocalProtocols dnssd
DefaultAuthType Basic
WebInterface no
IdleExitTimeout 60


- -- 
Yves-Alexis
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Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-05-25 Thread Brian Potkin
On Fri 25 May 2018 at 21:23:13 +0200, Francesco Poli wrote:

> On Fri, 25 May 2018 19:23:20 +0100 Brian Potkin wrote:
> 
> >   3. No IdleExitTimeout in cupsd.conf. The default is 60 seconds.
> 
> I have instead:
> 
>   $ grep IdleExit /etc/cups/cupsd.conf 
>   IdleExitTimeout 60
> 
> I can try without this option set, even though I would prefer to have
> the opportunity to set a different timeout, should I decide so...

I also used IdleExitTimeout 20 in my tests. The outcome was the same.

> > 
> >   4. 'systemctl daemon-reload' and 'systemctl restart cups'.
> 
> That's what I did after enabling socket activation, too.
> 
> > 
> > a) lpq, lpadmin and lpstat access cupsd and all lead to its becoming
> >inactive after the 60 seconds timeout is over. The behaviour is
> >reliable and consistent.
> [...]
> 
> OK, that's more or less consistent with what I saw.
> 
> > 
> > b) Setting up a print queue:
> > 
> >lpadmin -p testq -v file:/dev/null -E -m drv:///sample.drv/generic.ppd
> > 
> >'lp -d ' consistently fails to have cupsd closing the listening
> >sockets.
> 
> That's what I am currently reporting as bug, yes.

We can agree on that.

> [...]
> > c) Using lpadmin or lpq after doing b) sees the scheduler never becoming
> >inactive. The commands in c) above return the system to the state in
> >a).
> > 
> > My view is that the failure of cupsd to process a printing job and act
> > on IdleExitTimeout is the important aspect. I have no explanation for
> > cupsd not exiting but would be interested in whether the behaviour is
> > widespread.
> > 
> > Yves-Alexis Perez (cc'ed) has an interest in socket activation working. I
> > wonder whether he observes the behaviour described in b) when printing?
> > Yves-Alexis?
> 
> Fine, I am looking forward to reading additional information from
> people more knowledgeable than me!

People's experiences will determine decisions.

Did using socket activation on stretch ever work for you when printing?

Cheers,

Brian.



Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-05-25 Thread Francesco Poli
On Fri, 25 May 2018 19:23:20 +0100 Brian Potkin wrote:

> On Mon 21 May 2018 at 21:53:38 +0200, Francesco Poli (wintermute) wrote:
> 
> > Dear Debian Printing Team,
> > this bug report is a sort of "sequel" of #894762...
[...]
> > Why does cupsd fail to exit?
> > What's wrong?
> > 
> > Please help me.
> > 
> > Thanks for your time!
> 
> Thanks for pursuing the issue.
> 
> It is some time since I last looked at socket activation of cupsd. My
> experience wasn't the best then either. My setup:
> 
>   1. 'cupsctl WebInterface=no LogLevel=debug2'
> 
>  From https://github.com/apple/cups/issues/4874;
> 
>  > Finally, the systemd support code explicitly disables idle
>  > exit when the web interface is enabled,...

I have this too:

  $ grep WebInterface /etc/cups/cupsd.conf 
  WebInterface No

> 
>   2. cp /usr/share/doc/cups-daemon/examples/cups-socket.localhost.conf \
>  /etc/systemd/system/cups.socket.d/

Same here:

  $ diff -sq /usr/share/doc/cups-daemon/examples/cups-socket.localhost.conf \
 /etc/systemd/system/cups.socket.d/
  Files /usr/share/doc/cups-daemon/examples/cups-socket.localhost.conf and 
/etc/systemd/system/cups.socket.d/cups-socket.localhost.conf are identical

> 
>   3. No IdleExitTimeout in cupsd.conf. The default is 60 seconds.

I have instead:

  $ grep IdleExit /etc/cups/cupsd.conf 
  IdleExitTimeout 60

I can try without this option set, even though I would prefer to have
the opportunity to set a different timeout, should I decide so...

> 
>   4. 'systemctl daemon-reload' and 'systemctl restart cups'.

That's what I did after enabling socket activation, too.

> 
> a) lpq, lpadmin and lpstat access cupsd and all lead to its becoming
>inactive after the 60 seconds timeout is over. The behaviour is
>reliable and consistent.
[...]

OK, that's more or less consistent with what I saw.

> 
> b) Setting up a print queue:
> 
>lpadmin -p testq -v file:/dev/null -E -m drv:///sample.drv/generic.ppd
> 
>'lp -d ' consistently fails to have cupsd closing the listening
>sockets.

That's what I am currently reporting as bug, yes.

[...]
> c) Using lpadmin or lpq after doing b) sees the scheduler never becoming
>inactive. The commands in c) above return the system to the state in
>a).
> 
> My view is that the failure of cupsd to process a printing job and act
> on IdleExitTimeout is the important aspect. I have no explanation for
> cupsd not exiting but would be interested in whether the behaviour is
> widespread.
> 
> Yves-Alexis Perez (cc'ed) has an interest in socket activation working. I
> wonder whether he observes the behaviour described in b) when printing?
> Yves-Alexis?

Fine, I am looking forward to reading additional information from
people more knowledgeable than me!



-- 
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 There's not a second to spare! To the laboratory!
. Francesco Poli .
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Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-05-25 Thread Brian Potkin
On Mon 21 May 2018 at 21:53:38 +0200, Francesco Poli (wintermute) wrote:

> Dear Debian Printing Team,
> this bug report is a sort of "sequel" of #894762...
> 
> After some preliminary tests, I concluded that socket activation
> was working again.
> 
> Well, I was wrong!   :-(
> 
> After some further testing, I found out the following misbehavior.
> 
>  a) in my preliminary tests, the "lpq" command correctly woke cupsd up,
> and the daemon correclty exited after 60 s of inactivity
> (I have set "IdleExitTimeout 60" in /etc/cups/cupsd.conf)

I can reproduce this.
  
>  b) on the other hand, if I print something with the "lpr" command, cupsd
> is correctly started, but it seems to never exit for inactivity:

I can reproduce this too.
 
> $ systemctl status cups.service
> ● cups.service - CUPS Scheduler
>Loaded: loaded (/lib/systemd/system/cups.service; enabled; vendor 
> preset: ena
>Active: active (running) since Mon 2018-05-21 11:59:07 CEST; 9h ago
>  Docs: man:cupsd(8)
>  Main PID: 15103 (cupsd)
> Tasks: 1 (limit: 4915)
>Memory: 6.6M
>CGroup: /system.slice/cups.service
>└─15103 /usr/sbin/cupsd -l
> 
> May 21 11:59:07 HOSTNAME systemd[1]: Started CUPS Scheduler.
> 
>   c) now, after manually quitting cupsd and after re-enabling socket
>  activation:
> 
>  # systemctl stop cups.service
>  # systemctl daemon-reload
>  # systemctl restart cups.socket
> 
>  an "lpq" command correctly starts cupsd (again), but the daemon
>  fails to exit after 60 s of inactivity

I cannot reproduce this. (Please see c) below).

> Why does cupsd fail to exit?
> What's wrong?
> 
> Please help me.
> 
> Thanks for your time!

Thanks for pursuing the issue.

It is some time since I last looked at socket activation of cupsd. My
experience wasn't the best then either. My setup:

  1. 'cupsctl WebInterface=no LogLevel=debug2'

 From https://github.com/apple/cups/issues/4874;

 > Finally, the systemd support code explicitly disables idle
 > exit when the web interface is enabled,...

  2. cp /usr/share/doc/cups-daemon/examples/cups-socket.localhost.conf \
 /etc/systemd/system/cups.socket.d/

  3. No IdleExitTimeout in cupsd.conf. The default is 60 seconds.

  4. 'systemctl daemon-reload' and 'systemctl restart cups'.

a) lpq, lpadmin and lpstat access cupsd and all lead to its becoming
   inactive after the 60 seconds timeout is over. The behaviour is
   reliable and consistent. An error_log after using lpadmin has:

I [25/May/2018:14:23:49 +0100] Expiring subscriptions...
d [25/May/2018:14:23:49 +0100] select_timeout: JobHistoryUpdate=0
d [25/May/2018:14:23:49 +0100] select_timeout(0): 28 seconds to write dirty 
config/state files

 lpadmin command completed; pause for 28 seconds

I [25/May/2018:14:24:17 +0100] Saving printers.conf...
I [25/May/2018:14:24:17 +0100] Generating printcap /run/cups/printcap...
I [25/May/2018:14:24:17 +0100] Saving subscriptions.conf...
D [25/May/2018:14:24:17 +0100] cupsdSetBusyState: newbusy="Not busy", 
busy="Dirty files"
I [25/May/2018:14:24:17 +0100] Expiring subscriptions...
d [25/May/2018:14:24:17 +0100] cupsdCheckJobs: 0 active jobs, sleeping=0, 
ac-power=-1, reload=0, curtime=1527254657
d [25/May/2018:14:24:17 +0100] select_timeout: JobHistoryUpdate=0
d [25/May/2018:14:24:17 +0100] select_timeout(0): 86400 seconds to do nothing

 28 seconds pause over. After 60 seconds IdleExitTimeout kicks in.
 Therefore, it is 88 seconds before 'systemctl status cups' shows cupsd as 
inactive.
 The error_log does not record any of the following lines when 'lp -d' is 
used

I [25/May/2018:14:25:17 +0100] Printer sharing is off and there are no jobs 
pending, will restart on demand.
I [25/May/2018:14:25:17 +0100] Scheduler shutting down normally.
d [25/May/2018:14:25:17 +0100] cupsdAddEvent(event=server-stopped, 
dest=(nil)(), job=(nil)(0), text="Scheduler shutting
down normally.", ...)
d [25/May/2018:14:25:17 +0100] cupsd_send_notification(sub=0xf830b0(4), 
event=0xf415e0(server-stopped))
d [25/May/2018:14:25:17 +0100] sub->pipe=14
d [25/May/2018:14:25:17 +0100] cupsd_send_notification(sub=0xf831d0(6), 
event=0xfa67b0(server-stopped))
d [25/May/2018:14:25:17 +0100] sub->pipe=15
D [25/May/2018:14:25:17 +0100] cupsdMarkDirty(S)
D [25/May/2018:14:25:17 +0100] cupsdSetBusyState: newbusy="Dirty files", 
busy="Not busy"
d [25/May/2018:14:25:17 +0100] cupsdCloseAllClients() Clients=0

 cupsd stops listening.

d [25/May/2018:14:25:17 +0100] cupsdStopListening: closing all listen sockets.
d [25/May/2018:14:25:17 +0100] cupsdPauseListening: Clearing input bits...
d [25/May/2018:14:25:17 +0100] cupsdRemoveSelect(fd=5)
d [25/May/2018:14:25:17 +0100] cupsdRemoveSelect(fd=4)
d [25/May/2018:14:25:17 +0100] cupsdRemoveSelect(fd=3)
d [25/May/2018:14:25:17 +0100] cupsdEndProcess(pid=11543, force=0)
d [25/May/2018:14:25:17 +0100] cupsdEndProcess(pid=11544, force=0)
d 

Bug#899259: cups-daemon: with IdleExitTimeout 60, fails to exit after 60 s of inactivity

2018-05-21 Thread Francesco Poli (wintermute)
Package: cups-daemon
Version: 2.2.7-5
Severity: normal

Dear Debian Printing Team,
this bug report is a sort of "sequel" of #894762...

After some preliminary tests, I concluded that socket activation
was working again.

Well, I was wrong!   :-(

After some further testing, I found out the following misbehavior.

 a) in my preliminary tests, the "lpq" command correctly woke cupsd up,
and the daemon correclty exited after 60 s of inactivity
(I have set "IdleExitTimeout 60" in /etc/cups/cupsd.conf)
 
 b) on the other hand, if I print something with the "lpr" command, cupsd
is correctly started, but it seems to never exit for inactivity:

$ systemctl status cups.service
● cups.service - CUPS Scheduler
   Loaded: loaded (/lib/systemd/system/cups.service; enabled; vendor 
preset: ena
   Active: active (running) since Mon 2018-05-21 11:59:07 CEST; 9h ago
 Docs: man:cupsd(8)
 Main PID: 15103 (cupsd)
Tasks: 1 (limit: 4915)
   Memory: 6.6M
   CGroup: /system.slice/cups.service
   └─15103 /usr/sbin/cupsd -l

May 21 11:59:07 HOSTNAME systemd[1]: Started CUPS Scheduler.

  c) now, after manually quitting cupsd and after re-enabling socket
 activation:

 # systemctl stop cups.service
 # systemctl daemon-reload
 # systemctl restart cups.socket

 an "lpq" command correctly starts cupsd (again), but the daemon
 fails to exit after 60 s of inactivity



Why does cupsd fail to exit?
What's wrong?

Please help me.

Thanks for your time!


-- System Information:
Debian Release: buster/sid
  APT prefers testing
  APT policy: (800, 'testing'), (500, 'unstable')
Architecture: amd64 (x86_64)

Kernel: Linux 4.16.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8), 
LANGUAGE=en_US:en (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages cups-daemon depends on:
ii  adduser   3.117
ii  bc1.07.1-2+b1
ii  dpkg  1.19.0.5+b1
ii  libavahi-client3  0.7-4
ii  libavahi-common3  0.7-4
ii  libc6 2.27-3
ii  libcups2  2.2.7-5
ii  libcupsmime1  2.2.7-5
ii  libdbus-1-3   1.12.8-2
ii  libgssapi-krb5-2  1.16-2
ii  libpam0g  1.1.8-3.7
ii  libpaper1 1.1.24+nmu5
ii  libsystemd0   238-4
ii  lsb-base  9.20170808
ii  procps2:3.3.14-1+b1
ii  ssl-cert  1.0.39

Versions of packages cups-daemon recommends:
pn  avahi-daemon  
ii  colord1.3.3-2
ii  cups-browsed  1.20.3-1+b1

Versions of packages cups-daemon suggests:
ii  cups 2.2.7-5
ii  cups-bsd 2.2.7-5
ii  cups-client  2.2.7-5
ii  cups-common  2.2.7-5
ii  cups-filters [foomatic-filters]  1.20.3-1+b1
pn  cups-pdf 
ii  cups-ppdc2.2.7-5
ii  cups-server-common   2.2.7-5
ii  foomatic-db  20180306-1
ii  ghostscript  9.22~dfsg-2.1
pn  hplip
ii  poppler-utils0.63.0-2
ii  printer-driver-gutenprint5.2.13-2+b1
ii  printer-driver-hpcups3.17.10+repack0-5
pn  smbclient
ii  udev 238-4

-- no debconf information