START A HADOOP JOB FROM A WEB PAGE

Hey I am supposed to start a hadoop job from a web page. I am not sure how to do it. I use apache2 and using php i must start the hadoop job. I am not sure how to do it. I tried putting it in a .sh file and called it from apache2. but it is not working. but if i run the script from 'hduser' i am able to run the program. Can anyone help me with this regard?

Thanks in advance.