Munin contributed plugins

#!/usr/bin/env python3

"""

=head1 NAME

docker_ - Docker wildcard-plugin to monitor a L<Docker|https://www.docker.com> host.

This wildcard plugin provides at the moment only the suffixes C<containers>, C<images>, C<status>,

C<volumes>, C<cpu> and C<memory>.

=head1 INSTALLATION

- Copy this plugin in your munin plugins directory

- Install Python3 "docker" package

=over 2

    ln -s /usr/share/munin/plugins/docker_ /etc/munin/plugins/docker_containers

    ln -s /usr/share/munin/plugins/docker_ /etc/munin/plugins/docker_cpu

    ln -s /usr/share/munin/plugins/docker_ /etc/munin/plugins/docker_images

    ln -s /usr/share/munin/plugins/docker_ /etc/munin/plugins/docker_memory

    ln -s /usr/share/munin/plugins/docker_ /etc/munin/plugins/docker_status

    ln -s /usr/share/munin/plugins/docker_ /etc/munin/plugins/docker_volumes

=back

After the installation you need to restart your munin-node:

=over 2

    systemctl restart munin-node

=back

=head1 CONFIGURATION

This plugin need to run as root, you need to create a file named docker placed in the

directory /etc/munin/plugin-conf.d/ with the following config (you can also use

Docker environment variables here as described in

https://docs.docker.com/compose/reference/envvars/):

=over 2

    [docker_*]

    user root

    env.DOCKER_HOST unix://var/run/docker.sock

=back

"""

import os

import sys

import docker

from multiprocessing import Process, Queue

def print_containers_status(client):

    running = 0

    paused = 0

    created = 0

    restarting = 0

    removing = 0

    exited = 0

    dead = 0

    for container in client.containers.list():

        if container.status == 'running':

            running += 1

        elif container.status == 'paused':

            paused += 1

        elif container.status == 'created':

            created += 1

        elif container.status == 'restarting':

            restarting += 1

        elif container.status == 'removing':

            removing += 1

        elif container.status == 'exited':

            exited += 1

        elif container.status == 'dead':

            dead += 1

    print('running.value', running)

    print('paused.value', paused)

    print('created.value', created)

    print('restarting.value', restarting)

    print('removing.value', removing)

    print('exited.value', exited)

    print('dead.value', dead)

def get_container_stats(container, q):

    q.put(container.stats(stream=False))

def parallel_container_stats(client):

    proc_list = []

    stats = {}

    for container in client.containers.list():

        q = Queue()

        p = Process(target=get_container_stats, args=(container, q))

        proc_list.append({'proc': p, 'queue': q, 'container': container})

        p.start()

    for proc in proc_list:

        proc['proc'].join()

        stats[proc['container']] = proc['queue'].get()

    return stats.items()

def print_containers_cpu(client):

    for container, stats in parallel_container_stats(client):

        cpu_count = len(stats["cpu_stats"]["cpu_usage"]["percpu_usage"])

        cpu_percent = 0.0

        cpu_delta = float(stats["cpu_stats"]["cpu_usage"]["total_usage"]) \

            - float(stats["precpu_stats"]["cpu_usage"]["total_usage"])

        system_delta = float(stats["cpu_stats"]["system_cpu_usage"]) \

            - float(stats["precpu_stats"]["system_cpu_usage"])

        if system_delta > 0.0:

            cpu_percent = cpu_delta / system_delta * 100.0 * cpu_count

        print(container.name + '.value', cpu_percent)

def print_containers_memory(client):

    for container, stats in parallel_container_stats(client):

        print(container.name + '.value', stats['memory_stats']['stats']['total_rss'])

def main():

    try:

        mode = sys.argv[1]

    except IndexError:

        mode = ""

    wildcard = sys.argv[0].split("docker_")[1].split("_")[0]

    if mode == "suggest":

        print("containers")

        print("cpu")

        print("images")

        print("memory")

        print("status")

        print("volumes")

    client = docker.from_env()

    if wildcard == "status":

        if mode == "config":

            print("graph_title Docker status")

            print("graph_vlabel containers")

            print("graph_category virtualization")

            print("running.label RUNNING")

            print("paused.label PAUSED")

            print("created.label CREATED")

            print("restarting.label RESTARTING")

            print("removing.label REMOVING")

            print("exited.label EXITED")

            print("dead.label DEAD")

        else:

            print_containers_status(client)

    elif wildcard == "containers":

        if mode == "config":

            print("graph_title Docker containers")

            print("graph_vlabel containers")

            print("graph_category virtualization")

            print("containers_quantity.label Containers")

        else:

            print('containers_quantity.value', len(client.containers.list()))

    elif wildcard == "images":

        if mode == "config":

            print("graph_title Docker images")

            print("graph_vlabel images")

            print("graph_category virtualization")

            print("images_quantity.label Images")

        else:

            print('images_quantity.value', len(client.images.list()))

    elif wildcard == "volumes":

        if mode == "config":

            print("graph_title Docker volumes")

            print("graph_vlabel volumes")

            print("graph_category virtualization")

            print("volumes_quantity.label Volumes")

        else:

            print('volumes_quantity.value', len(client.volumes.list()))

    elif wildcard == "cpu":

        if mode == "config":

            graphlimit = str(os.cpu_count() * 100)

            print("graph_title Docker containers CPU usage")

            print("graph_args --base 1000 -r --lower-limit 0 --upper-limit " + graphlimit)

            print("graph_scale no")

            print("graph_period second")

            print("graph_vlabel CPU usage (%)")

            print("graph_category virtualization")

            print("graph_info This graph shows docker container CPU usage.")

            for container in client.containers.list():

                print("{}.label {}".format(container.name, container.name))

        else:

            print_containers_cpu(client)

    elif wildcard == "memory":

        if mode == "config":

            print("graph_title Docker containers memory usage")

            print("graph_args --base 1024 -l 0")

            print("graph_vlabel Bytes")

            print("graph_category virtualization")

            print("graph_info This graph shows docker container memory usage.")

            for container in client.containers.list():

                print("{}.label {}".format(container.name, container.name))

        else:

            print_containers_memory(client)

if __name__ == '__main__':

    main()