satisfy shellcheck

[log-quiet] / sysd-mail-once

diff --git a/sysd-mail-once b/sysd-mail-once
index 6e6807686a43c3e7f78a6c93b556533da9e8c02a..2c9d0263748e9b715acddb5bf3c0d57d28bb1dd9 100755 (executable)
--- a/sysd-mail-once
+++ b/sysd-mail-once
@@ -1,5 +1,12 @@
 #!/bin/bash
 #!/bin/bash

-# Copyright (C) 2016 Ian Kelling
+# I, Ian Kelling, follow the GNU license recommendations at
+# https://www.gnu.org/licenses/license-recommendations.en.html. They
+# recommend that small programs, < 300 lines, be licensed under the
+# Apache License 2.0. This file contains or is part of one or more small
+# programs. If a small program grows beyond 300 lines, I plan to switch
+# its license to GPL.
+
+# Copyright 2024 Ian Kelling

 
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.
 
 # Licensed under the Apache License, Version 2.0 (the "License");
 # you may not use this file except in compliance with the License.


@@ -14,16 +21,24 @@
 # limitations under the License.
 
 
 # limitations under the License.
 
 

+

 set -eE -o pipefail
 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
 
 errors=3
 set -eE -o pipefail
 trap 'echo "$0:$LINENO:error: \"$BASH_COMMAND\" returned $?" >&2' ERR
 
 errors=3

-cbase=$HOME/sysd-mail-once-state
-case "$1" in
+tmp=(~)
+cbase="${tmp[0]}/sysd-mail-once-state"
+to=root
+dryrun=false
+print_all=false
+while [[ $1 == -* ]]; do
+  case "$1" in

     -h|--help)
     -h|--help)

-        cat <<EOF
-Usage: sysd-log-once [-ERRORS] SERVICE COMMAND [ARGS...]
-For systemd timers, email on repeated failure & success after failure.
+      cat <<EOF
+Usage: sysd-mail-once [-t TO_ADDRESS] [-ERRORS] SERVICE COMMAND [COMMAND_ARGS...]
+
+For use with systemd timers, to email (with exim) on repeated failure &
+success after failure.

 
 In the service triggered by the timer, prepend this script to the ExecStart.
 The email will contain the service's logs for the last ERRORS runs.
 
 In the service triggered by the timer, prepend this script to the ExecStart.
 The email will contain the service's logs for the last ERRORS runs.


@@ -31,50 +46,142 @@ The email will contain the service's logs for the last ERRORS runs.
 
 Stores error counts in $cbase
 
 
 Stores error counts in $cbase
 

--ERRORS:  ERRORS is the number of failurs to accumulate before mailing the error.
-          Default is 3.
+-ERRORS         ERRORS is the number of failurs to accumulate before mailing the error.
+                Default is 3.
+
+-a              Email the logs of all errors intead of just the last one.
+-t TO_ADDRESS   Address to email about errors
+-n              Dry run. Execute command but only print out what we would do in response.

 EOF
 EOF

-        exit 0
-        ;;
+      exit 0
+      ;;

     -[0-9]*)
     -[0-9]*)

-        errors=${1#-}
-        shift
-        ;;
-esac
-service=$1
+      errors=${1#-}
+      ;;
+    -a)
+      print_all=true
+      ;;
+    -t)
+      to="$2"
+      shift
+      ;;
+    -n)
+      dryrun=true
+      ;;
+    *)
+      echo "error: unexpected arg: $1"
+      exit 1
+      ;;
+  esac
+  shift
+done
+
+if (( $# < 2 )); then
+  echo "error: expected at least 2 args after options. args:"
+  exit 1
+fi
+
+service="$1"

 shift
 
 shift
 

-c=$cbase/$service

 
 

-glob="$c[0-9]*"
+# maybe run, depending on $dryrun
+m() {
+  if $dryrun; then
+    printf "%s\n" "$*"
+  else
+    "$@"
+  fi
+}
+# maybe run, with stdin
+mi() {
+  if $dryrun; then
+    printf "%s <<'EOF'\n" "$*"
+    cat
+    echo EOF
+  else
+    "$@"
+  fi
+}
+e() {
+  if $dryrun; then
+    printf "dryrun: %s\n" "$*"
+  fi
+}
+
+c=$cbase/$service # c for command file path base
+
+e "c=$c"
+
+glob="${c}[0-9]*"

 arr=($glob); file="${arr[0]}"; [[ $glob != "$file" ]] || file=
 arr=($glob); file="${arr[0]}"; [[ $glob != "$file" ]] || file=

-u=${USER:-root}
-[[ -d $cbase ]] || mkdir -p $cbase
+if [[ $file ]]; then
+  e "file=$file"
+fi

 
 

-if [[ ! $file ]]; then
-    cursor=$(journalctl --show-cursor -qn0|sed 's/^\s*--\scursor:\s*//')
+if ! [[ -d $cbase ]]; then
+  mkdir -p $cbase

 fi
 fi

-if "$@"; then
-    if [[ $file ]]; then
-        rm -f $file
-        if [[ $file == $c$errors ]]; then
-            echo | mail -s "$HOSTNAME: $service success" $u@localhost
+
+
+code=0
+"$@" || code=$?
+if (( code )); then
+  send_mail=false
+  cursor=$(journalctl --show-cursor -qn0|sed 's/^\s*--\scursor:\s*//')
+  if [[ $file ]]; then
+    i=${file#"$c"}
+    if (( i < errors )); then
+      new_file=$c$((i+1))
+      m mv $file $new_file
+      file=$new_file
+      if [[ $file == $c$errors ]]; then
+        send_mail=true
+      else
+        if $dryrun; then
+          printf "dryrun: appending to file $file: %s\n" "$cursor"
+        else
+          printf "%s\n" "$cursor" >>$file

         fi
         fi

+      fi

     fi
     fi

-else # $@ failed
-    if [[ $file ]]; then
-        i=${file#$c}
-        if (( i < errors )); then
-            new_file=$c$((i+1))
-            mv $file $new_file
-            file=$new_file
-            if [[ $file == $c$errors ]]; then
-                journalctl -u $service.service --after-cursor=$(<$file) | \
-                    mail -s "$HOSTNAME: $service failure" $u@localhost
-            fi
-        fi
+  else
+    file=${c}1
+    if $dryrun; then
+      printf "dryrun: creating $file, contents: %s\n" "$cursor"
+    else
+      printf "%s\n" "$cursor" >$file
+    fi
+    if (( errors == 1 )); then
+      send_mail=true
+    fi
+  fi
+  if $send_mail; then
+    if $print_all; then
+      cursor=$(head -n1 $file)

     else
     else

-        file=${c}1
-        printf "%s\n" "$cursor" >$file
+      cursor=$(tail -n1 $file)
+    fi
+    echo "sysd-mail-once: emailing on $errors errors. exit code: $code"
+    mi exim -odf -t <<EOF
+To: $to
+From: $(id -u -n)@$(hostname -f)
+Subject: $HOSTNAME: $service exit code: $code
+
+$(journalctl -u $service.service --after-cursor="$cursor")
+EOF
+  fi
+else
+  if [[ $file ]]; then
+    m rm -f $file
+    if [[ $file == $c$errors ]]; then
+      echo "sysd-mail-once: emailing success after >= $errors errors."
+      mi exim -odf -t <<EOF
+To: $to
+From: $(id -u -n)@$(hostname -f)
+Subject: $HOSTNAME: $service success
+
+EOF

     fi
     fi

+  fi

 fi
 fi