#!/bin/sh

set -eu

: << =cut

=head1 NAME

jenkins_builds_and_jobs - Plugin to track statistics for jenkins builds and jobs

=head1 CONFIGURATION

[jenkins_builds_and_jobs]
env.jenkins_update_interval 15
env.jenkins_job_dir /var/lib/jenkins/jobs
env.build_process_regex /tmp/hudson

jenkins_update_interval: minimum number of minutes between successive
    update operations (adjust according to your resource limits)
    Default: 15
jenkins_job_dir: jenkins data directory for build logs
build_process_regex: distinct regular expression identifying running build processes

=head1 AUTHOR

Contributed by Holger Levsen. I wrote and used them first for
https://jenkins.debian.net and very much like to hear about
other users of these plugins! Please do tell me!

Use at your own risk and monitor the resource usage of the plugins
too - it will vary depending on your setup!

Patches, postcards and pancakes are all very much welcome!

=head1 LICENSE

Copyright 2012-2014 Holger Levsen <holger@layer-acht.org>
Copyright 2018 Lars Kruse <devel@sumpfralle.de>

Released under the GPLv2.

=head1 MAGIC MARKERS

 #%# family=auto
 #%# capabilities=autoconf

=cut

# shellcheck disable=SC1090
. "$MUNIN_LIBDIR/plugins/plugin.sh"

jenkins_update_interval=${jenkins_update_interval:-15}
jenkins_job_dir=${jenkins_job_dir:-/var/lib/jenkins/jobs}
build_process_regex=${build_process_regex:-/tmp/hudson}

plugin_name=$(basename "$0")

is_multigraph "$@"

if [ "${1:-}" = "autoconf" ]; then
	if [ -d "$jenkins_job_dir" ]; then
		echo yes
	else
		echo "no ($jenkins_job_dir not found)"
	fi
	exit 0
fi

STATEFILE=$MUNIN_PLUGSTATE/$(basename "$0")


get_job_prefixes() {
	find "$jenkins_job_dir" -maxdepth 1 -mindepth 1 -type d -print0 \
		| xargs -0 -r -n 1 basename \
		| cut -d "_" -f 1 \
		| sort -f -u
}


# count the result states from a jenkins jobs log
count_job_result_states() {
	awk '
		BEGIN { success=0; unstable=0; failure=0; unknown=0; IGNORECASE=1; }
		{
			if (/success/) success+=1;
			else if (/unstable/) unstable+=1;
			else if (/(failure|aborted)/) failure+=1;
			else unknown+=1;
		}
		END {
			print "success", success;
			print "unstable", unstable;
			print "failure", failure;
			print "unknown", unknown;
		}'
}


# Parse the result states from log files below "builds" directories.
# The base directories are determined by appending a "*" (for globbing) to the
# given parameter. The output consists of key/value pairs (state and count)
# for each possible state.
process_job_log_results() {
	local dir_prefix="$1"
	find "$dir_prefix"*/builds/ -mindepth 1 -maxdepth 1 -type d -print0 2>/dev/null \
		| xargs -0 -r -I '{}' find '{}' -mindepth 1 -maxdepth 1 -type f -name 'log' -print0 \
		| xargs -0 -r tail --quiet -n 1 \
		| count_job_result_states
}


do_config() {
	JOB_PREFIXES=$(get_job_prefixes)
	echo "multigraph ${plugin_name}_builds"
	echo 'graph_title Jenkins Builds in the last 24h'
	echo 'graph_args --base 1000 -l 0 '
	echo 'graph_scale no'
	echo 'graph_total total'
	echo 'graph_vlabel Jenkins Builds per category in the last 24h'
	echo 'graph_category devel'
	for PREFIX in $JOB_PREFIXES; do
		echo "jenkins_builds_$PREFIX.label $PREFIX"
		echo "jenkins_builds_$PREFIX.draw AREASTACK"
	done

	echo "multigraph ${plugin_name}_builds_results"
	echo 'graph_title Jenkins Builds results summary'
	echo 'graph_args --base 1000 -l 0 '
	echo 'graph_scale no'
	echo 'graph_total total'
	echo 'graph_vlabel Jenkins Builds results summary'
	echo 'graph_category devel'
	for STATE in success unstable failure unknown; do
		echo "${STATE}.label ${STATE}"
		echo "${STATE}.draw AREASTACK"
	done

	for PREFIX in $JOB_PREFIXES; do
		echo "multigraph ${plugin_name}_builds_results.prefix_$PREFIX"
		echo "graph_title Jenkins Builds results for $PREFIX"
		echo 'graph_args --base 1000 -l 0 '
		echo 'graph_scale no'
		echo 'graph_total total'
		echo 'graph_vlabel Jenkins Builds results'
		echo 'graph_category devel'
		for STATE in success unstable failure unknown; do
			echo "${STATE}.label ${STATE}"
			echo "${STATE}.draw AREASTACK"
		done
	done

	echo "multigraph ${plugin_name}_builds_running"
	echo 'graph_title Jenkins Builds running'
	echo 'graph_args --base 1000 -l 0 '
	echo 'graph_scale no'
	echo 'graph_vlabel Jenkins Builds currently running'
	echo 'graph_category devel'
	echo "jenkins_builds_running.label $PREFIX"
	echo "jenkins_builds_running.draw AREA"

	echo "multigraph ${plugin_name}_jobs"
	echo 'graph_title Jenkins Jobs'
	echo 'graph_args --base 1000 -l 0 '
	echo 'graph_scale no'
	echo 'graph_total total'
	echo 'graph_vlabel Jenkins Jobs per category'
	echo 'graph_category devel'
	for PREFIX in $JOB_PREFIXES; do
		echo "jenkins_jobs_$PREFIX.label $PREFIX"
		echo "jenkins_jobs_$PREFIX.draw AREASTACK"
	done
}


# Some operations may take quite a bit of time. These are updated periodically
# (see "jenkins_update_interval").
do_fetch_expensive() {
	JOB_PREFIXES=$(get_job_prefixes)
	echo "multigraph ${plugin_name}_builds"
	for PREFIX in $JOB_PREFIXES; do
		NR=$(find "$jenkins_job_dir/$PREFIX"*/builds/ -type d -mtime -1 2>/dev/null | wc -l)
		echo "jenkins_builds_$PREFIX.value $NR"
	done

	echo "multigraph ${plugin_name}_builds_results"
	process_job_log_results "$jenkins_job_dir/" | while read -r state count; do
		echo "${state}.value $count"
	done

	for PREFIX in $JOB_PREFIXES; do
		echo "multigraph ${plugin_name}_builds_results.prefix_$PREFIX"
		process_job_log_results "$jenkins_job_dir/$PREFIX" | while read -r state count; do
			echo "${state}.value $count"
		done
	done

	echo "multigraph ${plugin_name}_jobs"
	for PREFIX in $JOB_PREFIXES; do
		NR=$(find "$jenkins_job_dir" -maxdepth 1 -mindepth 1 -name "${PREFIX}*" -type d | wc -l)
		echo "jenkins_jobs_$PREFIX.value $NR"
	done
}


do_fetch_trivial() {
	echo "multigraph ${plugin_name}_builds_running"
	echo "jenkins_builds_running.value $(pgrep -f "$build_process_regex" | wc -l)"
}


do_fetch() {
	# Expensive operations are executed only periodically (see "jenkins_update_interval").
	# Delete statefile if it is older than "$jenkins_update_interval".
	find "$STATEFILE" -maxdepth 0 -mmin "+$jenkins_update_interval" -delete 2>&1 || true
	# Does the state file exist and is not outdated?
	# In this case just output its data and do not update the state.
	if [ -f "$STATEFILE" ]; then
		cat "$STATEFILE"
	else
		do_fetch_expensive | tee "$STATEFILE"
	fi

	# trivial operations are executed during every run
	do_fetch_trivial
}


case "${1:-}" in
	config)
		do_config
		if [ "${MUNIN_CAP_DIRTYCONFIG:-0}" = 1 ]; then do_fetch; fi
		;;
	"")
		do_fetch
		;;
	*)
		echo >&2 "Invalid action requested"
		exit 1
		;;
esac