#
#Services - starting stopping and logs.
#
#
#

#STARTING AND STOPING
#
#To demonstrate how to either keep a service going up or to kill it permanently from either the run script or the finish script, do this:

mkdir -vp /tmp/testservice
cat > /tmp/testservice/run << "EOF"
#!/bin/sh

#uncomment the next line to redirect stderr to stdout
#exec 2>&1

echo "started run ..."

if false;then
	echo "do something here with exec that doesn't finish"
	exec sleep 10d
else
	echo "condition failed catastrophically"
	echo "Don't restart the service"
#comment out the next line to make the service keep restarting
	echo "d" > supervise/control
fi
EOF

cat > /tmp/testservice/finish << "EOF"
#!/bin/sh

echo "started finish ... "
echo "run exited with code $1"
#echo "d" > supervise/control
EOF

#Start the service

cd /etc/runit/runsvdir/current
sudo ln -svfn /tmp/testservice testservice


#As it is the test at line 5 fails ( false always fails ) the service is then instructed to stop by line 12, the finish script will
#run and the service will not restart, if you comment out line 12 and restart the service like so

cd /etc/runit/runsvdir/current
sudo rm /etc/runit/runsvdir/current/testservice
sudo ln -svfn /tmp/testservice testservice


#As runit constantly checks the service folder every few seconds services can be started/stopped just by adding removing links,
#this also means you can add a service at any time just by adding a link

#LOGS

#A number of apps like cups etc handle their own logging and so a log folder is not needed, however it is easy enough
#to add a logger either for admin or debugging, like so:

mkdir -vp /tmp/testservice/log

cat > /tmp/testservice/log/run << "EOF"
#!/bin/bash

#stdin is connected to ../run stdout

while read
	do
#echo to console AND to logfile
		echo -n "message from log runscript ... "|tee -a /tmp/testservice.log
		echo "$REPLY"|tee -a /tmp/testservice.log
	done

EOF

#Basically the input to log/run is connected to the output of run AND finish so anything either of these two scripts send to stdout
#will be sent to log/run's stdin but ONLY if the log folder/files are present, if you want to capture stderr from the run/finish
#scripts you should redirect stderr to stdout uncomment the line at the start of the run file 'exec ...'.
#
#If you have set the service to keep restarting you will find that the log file and the console will pretty soon
#clog up with repeat entry's, so be aware , the simple way to prevent unwanted duplicates in the log file is just to pipe it
#to sort -u.
#
#And that is simple logging with runit.