How To Test Cron Job Code Example

Example: how to test crontab job

#!/bin/bash  # crontest # See https://github.com/Stabledog/crontest for canonical source.  # Test wrapper for cron tasks.  The suggested use is: # #  1. When adding your cron job, use all 5 stars to make it run every minute #  2. Wrap the command in crontest #         # #  Example: # #  $ crontab -e #     * * * * * /usr/local/bin/crontest $HOME/bin/my-new-script --myparams # #  Now, cron will run your job every minute, but crontest will only allow one #  instance to run at a time.   # #  crontest always wraps the command in "screen -d -m" if possible, so you can #  use "screen -x" to attach and interact with the job.    # #  If --bashdb is used, the command line will be passed to bashdb.  Thus you #  can attach with "screen -x" and debug the remaining command in context. # #  NOTES: #   - crontest can be used in other contexts, it doesn't have to be a cron job. #       Any place where commands are invoked without an interactive terminal and #       may need to be debugged. # #   - crontest writes its own stuff to /tmp/crontest.log # #   - If GNU screen isn't available, neither is --bashdb #  crontestLog=/tmp/crontest.log lockfile=$(if [[ -d /var/lock ]]; then echo /var/lock/crontest.lock; else echo /tmp/crontest.lock; fi ) useBashdb=false useScreen=$( if which screen &>/dev/null; then echo true; else echo false; fi ) innerArgs="$@" screenBin=$(which screen 2>/dev/null)  function errExit {     echo "[-err-] $@" | tee -a $crontestLog >&2 }  function log {     echo "[-stat-] $@" >> $crontestLog }  function parseArgs {     while [[ ! -z $1 ]]; do         case $1 in             --bashdb)                 if ! $useScreen; then                     errExit "--bashdb invalid in crontest because GNU screen not installed"                 fi                 if ! which bashdb &>/dev/null; then                     errExit "--bashdb invalid in crontest: no bashdb on the PATH"                 fi                  useBashdb=true                 ;;             --)                 shift                 innerArgs="$@"                 return 0                 ;;             *)                 innerArgs="$@"                 return 0                 ;;         esac         shift     done }  if [[ -z  $sourceMe ]]; then     # Lock the lockfile (no, we do not wish to follow the standard     # advice of wrapping this in a subshell!)     exec 9>$lockfile     flock -n 9 || exit 1      # Zap any old log data:     [[ -f $crontestLog ]] && rm -f $crontestLog      parseArgs "$@"      log "crontest starting at $(date)"     log "Raw command line: $@"     log "Inner args: $@"     log "screenBin: $screenBin"     log "useBashdb: $( if $useBashdb; then echo YES; else echo no; fi )"     log "useScreen: $( if $useScreen; then echo YES; else echo no; fi )"      # Were building a command line.     cmdline=""      # If screen is available, put the task inside a pseudo-terminal     # owned by screen.  That allows the developer to do a "screen -x" to     # interact with the running command:     if $useScreen; then         cmdline="$screenBin -D -m "     fi      # If bashdb is installed and --bashdb is specified on the command line,     # pass the command to bashdb.  This allows the developer to do a "screen -x" to     # interactively debug a bash shell script:     if $useBashdb; then         cmdline="$cmdline $(which bashdb) "     fi      # Finally, append the target command and params:     cmdline="$cmdline $innerArgs"      log "cmdline: $cmdline"       # And run the whole schlock:     $cmdline       res=$?      log "Command result: $res"       echo "[-result-] $(if [[ $res -eq 0 ]]; then echo ok; else echo fail; fi)" >> $crontestLog      # Release the lock:     9<&- fi