Check out carbone.io It’s not super powerful but does the trick for basic stuff. They have both self hosted and a cloud/paid version. pspdfkit.com might also have something for rendering PDFs as a service.
Just to say when evaluating pdf generation you probably need to consider accessibility at some stage and a lot of options are weak on this
Hi, there are some open sources likejsreports, carbone or reportbro but if you are looking generation to image you might try https://duply.co