Best way to build a integration solution for a SaaS platform
We're building integrations for our customers to extract data from legacy on-premise or cloud-hosted, but still old sources (think medical records, HR record servers, etc), centalize it, display it, etc.
These tools each have convoluted HTTP REST / SOAP APIs
How would you go about architecting a solution that allows a customer to self-serve connect to their sources and our product would then ingest and cache the data to be served to them in (sometimes) synthesized form?
We're looking at ETL tools etc. but any thoughts come to mind here?