While project data may come from many data structures such as messages, tasks, bugs, milestones etc so I think we can generate the pdf content for the project report. Do you have any suggestion for the nonbinary format?

I'd go for something like JSON, since you have "things" with several properties. That will easily hold any data you have and probably be converted easy as well while supported by many programming languages more or less natively for consumption. (Importing projects should be there as well so whole projects can be moved across instances.)

Sounds great. We will go for PDF for the end user (project manager and team members) and json format for developers :).