[CentOS] Triggering script from cron or web client

I have a Bash script, currently run a couple times an hour from cron, that 
pulls data from an old Windows DB by rsync, converts it to SQL, and injects 
it into a MySQL DB for display in a LAMP-based app. (Make and Perl are also 
involved to minimize the number of tables touched and to clean up the SQL 
generated by Pxlib.)

I'd like to add the ability to refresh the data immediately from the web 
app, but I don't want it to trample on the periodic script and corrupt the 
data.

I figure the ideal way to do this is to run the script in a loop in its own 
process, waiting on a semaphore that times out at the refresh period, and 
poke the semaphore from the web app to have it run before the next periodic 
cycle.

Are there existing frameworks to wrap this kind of thing in? Something that 
handles starting the loop at server startup, shutting it down at server 
halt, and handles the IPC between the web server and the service script.