check_dockercontainer_top

#!/bin/bash
# ======================================================================
#
# Check DOCKER PROCESSES
#
# requirements:
# - docker
# - sudo permissions on docker command
# - jq
#
# ----------------------------------------------------------------------
# Cli docs:
# https://docs.docker.com/engine/reference/commandline/docker/
# ----------------------------------------------------------------------
# 2024-01-26  v1.0  <axel.hahn@unibe.ch>      init
# 2024-01-29  v1.1  <axel.hahn@unibe.ch>      fix help;
# ======================================================================


. $(dirname $0)/inc_pluginfunctions
. $(dirname $0)/inc_dockerfunctions.sh

self_APPVERSION=1.1

# ----------------------------------------------------------------------
# FUNCTIONS
# ----------------------------------------------------------------------


# show help
function _showHelp(){
    local _self=$( basename $0 )
    cat <<EOH
$( ph.showImlHelpHeader )

Show counts and processes of docker containers.

It returns 
  CRITICAL if a created container is not running.
  OK if no container was created yet or all conmtainers are running.
  UNKNOWM if
    - docker or jq were not found
    - docker data were not fetched
    - docker cannot be connected

This check provides performance data.

USAGE:
  $_self [OPTIONS]

OPTIONS:

  General:
  -h, --help        this help
  -d, --debug       Debug; Flag: show docker env values.

  Connect to docker:
  -p, --path        Custom directory for docker binary
  -t, --target      Custom docker target; value for DOCKER_HOST
                    Needed only if Docker does not run on a unix socket or
                    multiple users run a rootless docker daemon.

EXAMPLES:
  $_self
    Show processes of all containers

  $_self -p /usr/bin
    Show processes of all containers. The docker binary will be searched in
    given path first - then in all other dirs of \$PATH

  $_self -d
    Show processes of all containers and json with docker env infos.

EOH
}

# ----------------------------------------------------------------------
# MAIN
# ----------------------------------------------------------------------

bOptDebug=0

while [[ "$#" -gt 0 ]]; do case $1 in
    -h|--help)        _showHelp; exit 0;;
    -d|--debug)       bOptDebug=1; shift;;
    -p|--path)        if ! grep ":{$2}:" <<< ":{$PATH}:" >/dev/null; then
                        PATH="$2:$PATH"; 
                      fi
                      shift; shift;;
    -t|--target)      export DOCKER_HOST="$2"; shift; shift;;
    *) echo "ERROR: Unknown parameter: $1"; _showHelp; exit 1;
esac; done

ph.require "docker"
ph.require "jq"

_detectDockerenv

# --- fetch data

data=$( sudo -n --preserve-env docker ps --format "{{ json . }}" 2>/dev/null )
_detectDockererror "$data"

# --- collect data

out=$(
echo "$data" | while read -r line; do
    id=$(   echo "$line" | jq -r ".ID")
    name=$( echo "$line" | jq -r ".Names")

    pslist=$( sudo -n --preserve-env docker top "$id" "-o user,pid,pcpu,pmem,command" 2>/dev/null )
    
    typeset -i ipLines; ipLines=$( echo "$pslist" | wc -l )-1
    echo "----------| $ipLines |-- $name (id: $id) ----- "
    echo "$pslist"
done
)

typeset -i iContainers; iContainers=$( echo "$data" | wc -l )
typeset -i iLines;      iLines=$( echo "$out" | wc -l )
typeset -i iProcesses;  iProcesses=$(( iLines-iContainers*2 ))

# --- output

ph.perfadd "processes" "$iProcesses" "" ""

ph.status "Docker processes: $iProcesses .. containers: $iContainers"
echo "$out"

# if -d was given then show debug infos too
test $bOptDebug -eq 1 && ( echo; echo "DEBUG: full docker system infos as json"; echo "$data" | jq ; _debugInfos)

ph.exit

# ----------------------------------------------------------------------