From: Ian Kelling Date: Sun, 27 Mar 2022 10:03:08 +0000 (-0400) Subject: simplify log once X-Git-Url: https://iankelling.org/git/?a=commitdiff_plain;h=0913504bf944ba89714f898cd45a4c85b4781bce;p=log-quiet simplify log once --- diff --git a/log-once b/log-once index 4a2b348..3aa3c76 100755 --- a/log-once +++ b/log-once @@ -6,23 +6,29 @@ append() { cat >> "$1" } log-once() { - local cbase c log x i out file o tmp + local cbase c log line i out file o tmp cbase=/var/local/cron-errors [[ $EUID == 0 ]] || cbase=$HOME/cron-errors - local help="Usage: log-once [OPTION]... LOG_NAME [LOG_MESSAGE...] + local help="Usage: some-command-that-outputs-on-error |& log-once [OPTION]... LOG_NAME -For cronjobs, email log on repeated failure and success after failure. - -Meant for use in cronjobs where LOG_MESSAGE or STDIN represents an error, +Main use case: in cronjobs where STDIN represents an error, but we only want to output that to STDOUT if we've seen this type of error ERRORS(default 3) number of times in a row, then we don't -want to output anything again until we've seen a success (an empty LOG_MESSAGE). +want to output anything again until we've seen a success: no standard input. + +Logs STDIN to /var/local/cron-errors/LOG_NAME\$error_count or +$HOME/cron-errors if not root, and keeps state in the same directory. + +-ERRORS: ERRORS is the number of errors to accumulate before outputing the error + + +You can emulate how cronjobs work by doing this for example: -Logs LOG_MESSAGE or STDIN to /var/local/cron-errors/LOG_NAME\$error_count -or $HOME/cron-errors if not root, and keeps -state in the same directory. + cmdname |& log-once | ifne mail -s 'cmdname failed' root@localhost --ERRORS: ERRORS is the number of errors to accumulate before outputing the error" +I could imagine a similar command that considers its non-option args to +be an error, but I haven't written it yet. +" errors=3 while true; do if [[ $1 == --help ]]; then @@ -42,17 +48,15 @@ state in the same directory. # todo, make option & make them overridable based on command line or env variable [[ -d $cbase ]] || mkdir -p $cbase c=$cbase/$log_name - # http://stackoverflow.com/questions/2456750/detect-presence-of-stdin-contents-in-shell-script log=false - if [[ $2 ]]; then - log=true - # read stdin for anything which is not just a newline - elif [[ ! -t 0 ]]; then - while read -r x; do - output+=( "$x" ) - [[ $x ]] && log=true - done - fi + while read -r line; do + output+=( "$line" ) + # If we find something that is not just a newline: + if [[ $line ]]; then + log=true + break + fi + done glob="$c[0-9]*" # file is error file indicating previous error tmp=($glob); file="${tmp[0]}" @@ -77,7 +81,7 @@ state in the same directory. out="tee -a" fi fi - $out $file <<<"log-once: $(date "+%A, %B %d, %r")" + $out $file <<<"log-once: $(date -R)" if [[ $2 ]]; then $out $file <<<"$*" else @@ -91,7 +95,7 @@ state in the same directory. if [[ $file ]]; then rm -f $file if [[ $file == $c$errors ]]; then - echo "log-once success after failure for $c" + echo "log-once: $(date -R): success after failure for $c" fi fi return 0