I’m looking for ways to generate PDFs on-the-fly, preferably using a command line tool, as this will be done from a web-based system.
My requirements include must work on Windows and Linux, should be able to convert Microsoft Word, Excel and HTML into PDF.
Also, the ability to concatenate or merge various documents into one PDF output file would be good.
Any suggestions? I would prefer to avoid applications that work as "printer drivers".
After doing some research, the best solution I found in the end that could handle all the file formats we needed converting, plus which ran on Linux and Windows was a beautifully elegant lightweight Python script called PyODConverter. This uses OpenOffice (which itself runs in server mode) to do the actual conversions, and it really works beautifully. I used a separate tool called PDFTK to do the PDF concatenation, as I found that ImageMagick loses a lot of information (and creates huge file sizes).
If you find PyODConverter too limited, there is also a more powerful heavyweight option written by the same guy called JODConverter.