I am trying to implement an automatic report generation tool for my clients .
I need to create reports in pdf format and i am very much comfortable in creating graphs using
If you can do this serverside and you are on a Unix based system, I would try wkhtmltopdf.
EDITS AFTER SOME TIME
Now a days, to do this serverside I would use the awesome phantomjs. I've been using this on a flot based project for some time and it works perfectly.