Is it possible to call multiple APIs using Splunk? To be more clear, have an API that will log in to the get sessionID and the other call that uses the sessionID to get the list of all elements.
Yes, that is the major purpose of the REST API Splunk provides.
Refer to https://docs.splunk.com/Documentation/Splunk/7.2.5/RESTUM/RESTusing which outlines how to authenticate to Splunk via REST, then use the sessionID to create a search, poll to check if it has finished, and then fetch the results once finalized.
was this successful because i am also interested in the approach.
I'm trying to call external REST API's using splunk, will it be possible?
You will need to develop your own script to call the REST endpoints. Usually, this is done in Python, but you can use any language you like.
If you configure this as a scripted input, the standard output of your script will be ingested by Splunk
