Send email at completion of CUPS print job

deerewright · 10-27-2015, 04:45 PM

I am running a headless raspberry pi for several functions, and have a cron job set to print a test page weekly to a network printer. I would like to have an email sent to confirm that the job has completed successfully. I know how to send an email about the cron job, but that only tells me the cron completed, not whether or not CUPS printed successfully or not.

Habitual · 10-27-2015, 05:22 PM

Have a grep in /var/log/cups for something like this:
grep "Print-Job successful-ok" /var/log/cups/*

Code:

localhost - - [22/Oct/2015:17:59:34 -0400] "POST /printers/HP_LaserJet_P2035 HTTP/1.1" 200 318756 Print-Job successful-ok
localhost - - [22/Oct/2015:04:21:00 -0400] "POST /printers/HP_LaserJet_P2035 HTTP/1.1" 200 251584 Print-Job successful-ok
localhost - - [09/Oct/2015:09:53:27 -0400] "POST /printers/HP_LaserJet_P2035 HTTP/1.1" 200 93552 Print-Job successful-ok

Hope that helps.

deerewright · 10-27-2015, 05:36 PM

Quote:

Originally Posted by Habitual

Have a grep in /var/log/cups for something like this:
grep "Print-Job successful-ok" /var/log/cups/*

Code:

localhost - - [22/Oct/2015:17:59:34 -0400] "POST /printers/HP_LaserJet_P2035 HTTP/1.1" 200 318756 Print-Job successful-ok
localhost - - [22/Oct/2015:04:21:00 -0400] "POST /printers/HP_LaserJet_P2035 HTTP/1.1" 200 251584 Print-Job successful-ok
localhost - - [09/Oct/2015:09:53:27 -0400] "POST /printers/HP_LaserJet_P2035 HTTP/1.1" 200 93552 Print-Job successful-ok

Hope that helps.

That returns no results on my system? Maybe I don't have my logs setup right?

deerewright · 10-27-2015, 05:47 PM

Quote:

Originally Posted by deerewright

That returns no results on my system? Maybe I don't have my logs setup right?

It is a network printer, so this works:

Code:

grep "Send-Document successful-ok" /var/log/cups/*

That does tell me the job completed, but I want to have either CUPS or a script to send me an email at the time it completes.

Habitual · 10-27-2015, 06:12 PM

perhaps you should show us this cron job.

deerewright · 10-27-2015, 07:15 PM

Crontab entry:

Code:

0 1 * * 2 lpr -p /path/to/file.pdf

Quote:

Windows assumes you're a dumb-ass. Linux demands that you prove it.

Have I proved it yet? :-)

Sefyir · 10-27-2015, 07:58 PM

You could either have the cronjob use a one-liner to do everything, or invoke a small bash script.
The former can be finicky but wouldn't require creating a script file while the latter would be simpler.

For the one-liner I suppose something like this may work

Code:

0 1 * * 2 lpr -p /path/to/file.pdf; grep "Send-Document successful-ok" /var/log/cups/* && echo 'Success with print job' mail -s Completion email@address

I'd be careful of cron interpreting the * and @ weirdly

Out of curiosity, if you run lpr -p /path/to/file.pdf, will it have a error code if it fails? Because you could skip the grep

Code:

0 1 * * 2 lpr -p /path/to/file.pdf && echo 'Success with print job' | mail -s Completion email@address

deerewright · 10-27-2015, 09:09 PM

Quote:

Originally Posted by Sefyir

You could either have the cronjob use a one-liner to do everything, or invoke a small bash script.
The former can be finicky but wouldn't require creating a script file while the latter would be simpler.

For the one-liner I suppose something like this may work

Code:

0 1 * * 2 lpr -p /path/to/file.pdf; grep "Send-Document successful-ok" /var/log/cups/* && echo 'Success with print job' mail -s Completion email@address

I'd be careful of cron interpreting the * and @ weirdly

Out of curiosity, if you run lpr -p /path/to/file.pdf, will it have a error code if it fails? Because you could skip the grep

Code:

0 1 * * 2 lpr -p /path/to/file.pdf && echo 'Success with print job' | mail -s Completion email@address

I used your second example, and it works. I do not get any error messages, but I kept getting my syntax wrong, and I would get a strange formatted email that basically repeated the cron command rather than 'Success..., etc.'

Once I got all my syntax right, it works fine. I just not sure if it is really telling me it printed or just that the cron job completed? Maybe I'll try to write a script that does the print and grep, and email, then cron the script?

Sefyir · 10-27-2015, 09:36 PM

Quote:

I just not sure if it is really telling me it printed or just that the cron job completed? Maybe I'll try to write a script that does the print and grep, and email, then cron the script?

&& means if the previous command succeeds, also do this command.

Eg, try these two commands

Code:

true && echo success
false && echo success

You'll notice when the command fails (with false), echo does not stdout Success.

deerewright · 10-27-2015, 10:13 PM

Thanks for all the help. Here is what I ended up with so far,

crontab:

Code:

0 1 * * 1 ~/weeklyprint.sh

weeklyprint.sh:

Code:

#!/bin/bash

lpr -P HP8500 /usr/share/cups/data/testprint /usr/share/cups/data/colortest.pdf

sleep 60

grep "Send-Document successful-ok" /var/log/cups/* | tail -5 >/var/log/pi/weeklyprint.log
echo "Success with print job" | mail -s "Weekly Print completed"  xxxxx@gmail.com </var/log/pi/weeklyprint.log

This seems to give me what I'm looking for, but just for my own edumacation

, anything I should change?

Also, It does not print "Success with Print job" in the body of the email, just the log file. Is there a way to get both, without using an attachment? Can you send multiple files in the body?

Sefyir · 10-27-2015, 11:04 PM

There might be a better way, but here's a hack that might do what you want.

Code:

grep "Send-Document successful-ok" /var/log/cups/* | tail -5 >/var/log/pi/weeklyprint.log
echo "Success with print job" | mail -s "Weekly Print completed"  xxxxx@gmail.com </var/log/pi/weeklyprint.log

This doesn't check for the success of the grep command. You can check for that with $?

Eg.

Code:

~ > true
~ > echo $?
0
~ > false
~ > echo $?
1
~ > true
~ > if [ $? == 0 ]; then echo success; fi
success

As for containing both messages, this is a bit of a hack I just came up with:

Code:

echo $(echo "Success with print job"; cat /var/log/pi/weeklyprint.log) | mail -s "Weekly Print completed"  xxxxx@gmail.com

deerewright · 10-27-2015, 11:18 PM

Quote:

Code:

~ > true
~ > echo $?
0
~ > false
~ > echo $?
1
~ > true
~ > if [ $? == 0 ]; then echo success; fi
success

Sorry, still learning....Where do I put that code? In the script, after the grep line? Then, the following?

Quote:

As for containing both messages, this is a bit of a hack I just came up with:

Code:

echo $(echo "Success with print job"; cat /var/log/pi/weeklyprint.log) | mail -s "Weekly Print completed"  xxxxx@gmail.com

Sefyir · 10-28-2015, 12:03 AM

Quote:

Where do I put that code?

Code:

grep "Send-Document successful-ok" /var/log/cups/* | tail -5 >/var/log/pi/weeklyprint.log
echo "Success with print job" | mail -s "Weekly Print completed"  xxxxx@gmail.com </var/log/pi/weeklyprint.log

I'm assuming your intended purpose of the two lines above is to search for "Send-Document successful-ok" with grep and if that is successful, to send a email saying "Success with print job" as the message.
Now, if it is not a success, what should the action be?

As the code is, no matter what it will send a "Success with print job" everytime it is executed since it never evaluates the result of the grep search.
This would be the basis of a if then statement.

Something like this:

Code:

grep "Send-Document successful-ok" /var/log/cups/* | tail -5 >/var/log/pi/weeklyprint.log
if [ $? == 0 ]
  then
    echo "Success with print job" | mail -s "Weekly Print completed"  xxxxx@gmail.com </var/log/pi/weeklyprint.log
  else
    command to give if stuff fails
fi

Or simplified as a one-liner

Code:

grep "Send-Document successful-ok" /var/log/cups/* | tail -5 >/var/log/pi/weeklyprint.log
if [ $? == 0 ]; then echo "Success with print job" | mail -s "Weekly Print completed"  xxxxx@gmail.com </var/log/pi/weeklyprint.log; fi

Assuming you understand what a if statement is meant for, $? is used to evaluate the error code of the previous command. Apologies if I didn't explain that well enough with my previous example. 0 is meant for no error, 1 is for error and other various numbers are used for specialized errors.
Since you're looking to send a email when the command resolves successfully, the if statement tests for $? equalling 0. If it does, it sends the email saying success. Otherwise, it does nothing. If you place commands in the command to give if stuff fails spot, it will run those commands if the if statement doesn't match.

deerewright · 10-28-2015, 12:56 AM

Got it! Thanks, that makes sense now...

BUT, I just realized that it will send a successful print message as long as it finds any "Send-Document successful-ok" messages in the log. So we need to find a way to limit it to the most recent (i.e. within the last few minutes), ideally.

I guess I could delete the log file before printing?

chrism01 · 10-28-2015, 06:00 AM

I'd try

Code:

#!/bin/bash

lpr -P HP8500 /usr/share/cups/data/testprint /usr/share/cups/data/colortest.pdf
if [[ $? -eq 0 ]]
then
    echo "Success with print job" | mail -s "Weekly Print completed"  xxxxx@gmail.com </var/log/pi/weeklyprint.log
else
    echo "Fail with print job" | mail -s "Weekly Print completed"  xxxxx@gmail.com </var/log/pi/weeklyprint.log
fi

You can tweak the msgs as reqd.