From 5e312a597d7046d8e75d2f0323f7acff2ce06243 Mon Sep 17 00:00:00 2001
From: Christoph <ckubu@oopen.de>
Date: Sat, 23 Oct 2021 14:48:35 +0200
Subject: [PATCH] check_local_webservice.sh: add parameter
 'CONFLICTING_SCRIPTS' - don't run if a conflicting other script is currently
 running.

---
 check_local_webservice.sh               | 101 ++++++++++++++----------
 conf/check_local_webservice.conf.sample |  12 ++-
 2 files changed, 70 insertions(+), 43 deletions(-)

diff --git a/check_local_webservice.sh b/check_local_webservice.sh
index 019cec5..7916343 100755
--- a/check_local_webservice.sh
+++ b/check_local_webservice.sh
@@ -5,7 +5,7 @@ script_name="$(basename $(realpath $0))"
 working_dir="$(dirname $(realpath $0))"
 conf_file="${working_dir}/conf/${script_name%%.*}.conf"
 
-LOCK_DIR="/tmp/check_local_webservice.LOCK"
+LOCK_DIR="/tmp/${script_name%%.*}.LOCK"
 
 RESTART_CHECK_FILE="/tmp/${script_name%%.*}.NEED-RESTART"
 
@@ -179,12 +179,70 @@ TIME_OUT_MAX="$(expr ${TIME_OUT} + 5)"
 # - Job is already running?
 # -------------
 
+
+# - Stop here, if these give scripts are running
+# -
+if [[ ${#CONFLICTING_SCRIPTS} -gt 0 ]] ; then
+
+   # - Try using a random start delay to prevent (or at least have a small chance) that 
+   # - conflicting scripts will both/all abort if they start at the same time.
+   # -
+   # - !! Notice !!
+   # - This only makes sense if a fixed LOCK directory is used, otherwise the process list 
+   # - (and NOT the LOCK-directory) is used to look for scripts running in parallel. 
+   # -
+   if [[ "$LOCK_DIR" = "/tmp/${script_name%%.*}.LOCK" ]]; then
+      _shift="$(( $RANDOM % 10 + 1 ))"
+      sleep  $(( $RANDOM % 25 + $_shift ))
+   fi
+
+   _stop_running=false
+   for _val in $CONFLICTING_SCRIPTS ; do
+
+      IFS=':' read -a _val_arr <<< "${_val}"
+
+      _script_name="$(basename ${_val_arr[0]})"
+
+      if [[ -n "${_val_arr[1]}" ]] ; then
+
+         if [[ "${_val_arr[1]}" = "CHECK_PROCESS_LIST" ]] ; then
+
+            check_string_ps="${_val_arr[0]}"
+            if ps -e f | grep -E "\s+${check_string_ps}" | grep -v grep | grep -v -E "\s+vim\s+" > /dev/null ; then
+               _stop_running=true
+            fi
+
+         elif [[ -d "${_val_arr[1]}" ]] ; then
+            _stop_running=true
+         fi
+
+      elif [[ -d "/tmp/${_script_name%%.*}.LOCK" ]]; then
+         _stop_running=true
+      fi
+
+      if $_stop_running ; then
+
+         echo ""
+         echo "[ Error ]: The \"${_script_name}\" script is currently running, but it conflicts with this script."
+         echo ""
+         echo "           Exiting now.."
+         echo ""
+
+         clean_up 1
+
+      fi # if $_stop_running ; then
+
+   done # for _val in $CONFLICTING_SCRIPTS ; do
+
+fi # if [[ ${#CONFLICTING_SCRIPTS} -gt 0 ]] ; then
+
+
 # - If job already runs, stop execution..
 # -
 if mkdir "$LOCK_DIR" 2> /dev/null ; then
 
    ## - Remove lockdir when the script finishes, or when it receives a signal
-   trap clean_up SIGHUP SIGINT SIGTERM
+   trap "clean_up 1" SIGHUP SIGINT SIGTERM
 
 else
 
@@ -208,45 +266,6 @@ else
 fi
 
 
-# - Stop here, if these give scripts are running
-# -
-if [[ ${#CONFLICTING_SCRIPTS} -gt 0 ]] ; then
-
-   _stop_running=false
-   for _val in $CONFLICTING_SCRIPTS ; do
-
-      IFS=':' read -a _val_arr <<< "${_val}"
-
-      _script_name="$(basename ${_val_arr[0]})"
-
-      if [[ -n "${_val_arr[1]}" ]] && [[ -d "${_val_arr[1]}" ]] ; then
-         _stop_running=true
-      else
-
-         check_string_ps="${_val_arr[0]}"
-
-         if ps -e f | grep -E "\s+${check_string_ps}" | grep -v grep | grep -v -E "\s+vim\s+" > /dev/null ; then
-            _stop_running=true
-         fi
-      fi
-
-      if $_stop_running ; then
-
-         echo ""
-         echo "[ Error ]: The \"${_script_name}\" script is currently running, but it conflicts with this script."
-         echo ""
-         echo "           Exiting now.."
-         echo ""
-
-         clean_up 1
-
-      fi
-
-      
-   done
-fi
-
-
 
 
 
diff --git a/conf/check_local_webservice.conf.sample b/conf/check_local_webservice.conf.sample
index d900d7f..6c2e99c 100644
--- a/conf/check_local_webservice.conf.sample
+++ b/conf/check_local_webservice.conf.sample
@@ -52,10 +52,18 @@ LOG_FILES_TO_MONITOR=""
 # - In addition to the script, a LOCK directory can also be specified which is 
 # - connected to it. 
 # - 
+# - If no fixed LOCK directory is connected to the script, set 
+# - this value to the constant 'CHECK_PROCESS_LIST'.
+# -
+# - If no value for the LOCK directory is given, the LOCK directory 
+# - '/tmp/<base-script_name>.LOCK' is assumed. 
+# - 
+# - 
 # - Example:
 # -    CONFLICTING_SCRIPTS="
-# -       /root/bin/monitoring/check_webservice_load.sh
-# -       /root/bin/monitoring/check_remote_websites.sh:/tmp/check_remote_websites.LOCK
+# -       /root/bin/monitoring/check_webservice_load.sh:CHECK_PROCESS_LIST
+# -       /root/bin/monitoring/check_remote_websites.sh
+# -    "
 # -
 # - Defaults to:
 # -    CONFLICTING_SCRIPTS="/root/bin/monitoring/check_webservice_load.sh"