Though I don't know too much about sharepoint, it seems they have an API that allows for HTTP Get requests. Look carefully at the hidden section on this page: https://docs.microsoft.com/en-us/sharepoint/dev/sp-add-ins/get-to-know-the-sharepoint-rest-service?t...
Based on the above you could use both the GetHTTP processor or the InvokeHTTP processor with a get method.
If this is the wrong way to access sharepoint, my general advice:
1. Figure out how sharepoint allows any program (whether it is nifi, python,...) to extract data.
2. From here it should be comparatively easy to figure out which processor you need to do this
- Dennis Jaheruddin
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