iankelling.org Git - log-quiet/blob - sysd-prom-fail

   1 #!/bin/bash
   2 # I, Ian Kelling, follow the GNU license recommendations at
   3 # https://www.gnu.org/licenses/license-recommendations.en.html. They
   4 # recommend that small programs, < 300 lines, be licensed under the
   5 # Apache License 2.0. This file contains or is part of one or more small
   6 # programs. If a small program grows beyond 300 lines, I plan to switch
   7 # its license to GPL.
   8
   9 # Copyright 2024 Ian Kelling
  10
  11 # Licensed under the Apache License, Version 2.0 (the "License");
  12 # you may not use this file except in compliance with the License.
  13 # You may obtain a copy of the License at
  14
  15 #     http://www.apache.org/licenses/LICENSE-2.0
  16
  17 # Unless required by applicable law or agreed to in writing, software
  18 # distributed under the License is distributed on an "AS IS" BASIS,
  19 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  20 # See the License for the specific language governing permissions and
  21 # limitations under the License.
  22
  23
  24
  25 # requires 1.4.0 to run with multiple units due to bug before that:
  26 # https://github.com/prometheus/node_exporter/pull/2475
  27
  28 set -eE -o pipefail
  29 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
  30
  31 if [[ ! $SERVICE_RESULT ]]; then
  32   echo "$0: error, no SERVICE_RESULT var."
  33   exit 1
  34 fi
  35
  36 ser_name="$1"
  37
  38 if [[ ! $ser_name ]]; then
  39   echo "$0: error, no arg service name passed."
  40   exit 1
  41 fi
  42
  43 dir=/var/lib/prometheus/node-exporter
  44 if [[ ! -e $dir  ]]; then
  45   exit 0
  46 fi
  47
  48 f=$dir/${ser_name}-result.prom
  49 ftmp=$f.$$
  50
  51
  52 write_count=false
  53 if [[ -s $f ]]; then
  54   # https://www.freedesktop.org/software/systemd/man/systemd.exec.html
  55   if [[ $SERVICE_RESULT != success ]]; then
  56     write_count=true
  57     read -r _ count <$f
  58     case $count in
  59       ''|*[!0-9]*)
  60         count=0
  61         ;;
  62       *)
  63         count=$(( count + 1 ))
  64         ;;
  65     esac
  66   fi
  67 else
  68   count=0
  69   write_count=true
  70 fi
  71
  72 if $write_count; then
  73   printf 'node_systemd_unit_result_fail_count{name="%s"} %s\n' "$ser_name" "$count" >$ftmp
  74   mv $ftmp $f
  75 fi