AWS EBS custom script run

Can any one tell me how to run the my custom script "run.sh" its kept on the application root directory I have added the commands in .ebextensions/static.config file and the code as below

 commands:
   update_script:
    command: run.sh

The commands is executing by EBS(Elasticbeanstalk) but its not getting the run.sh file as it is running from root directory of the machine. I wanted to know where the app is located so that I can run the "run.sh" script

Please let me know how to run my custom scripts.

Thank you in advance

Jagdish