如何根据日志消息重新启动脚本

Question

I have a java application and want to restart it when certain message appears in log the file. What I have tried so far is the following script:

#!/bin/bash

java -jar app.jar > app.log 2>&1
tail -f app.log | while read LOGLINE
do
   [[ "${LOGLINE}" == *"channel incative"* ]] && pkill -P $$ java &&  java -jar app.jar > app.log 2>&1
done

I run the scritp using the following command

nohup sh app.sh &

But it doesnt work as expected. Do you have any suggestion?

ps the java application is a legacy one coming from 3rd party, so I cannot do the logic in the application code itself.

Answer 1

When the "channel incative" string is found in the log, kill java and restart the script. The log file is cleared so that the "channel" string can be searched for again. Use sleep to give java process a little time to die.

#!/bin/bash
sleep 1
java -jar app.jar > app.log 2>&1
rm app.log 2> /dev/null
touch app.log
tail -f app.log | while read LOGLINE
do
   [[ "${LOGLINE}" == *"channel incative"* ]] && pkill -P $$ java && exec app.sh
done