REST API to Retrieve Content ID from UCM

Organization Name (Required - If you are an Oracle Partner, please provide the organization you are logging the idea on behalf of):

Blue Cross Blue Shield of Michigan

Description (Required):

I am posting a file to UCM through rest API. I need to then post this file in import management using below, but I have no way to retrieve InputFileContentId (content ID from UCM).

It seems odd that Oracle has a rest API to upload a file to UCM and a rest api for import management but no way to run the two APIs together.

/crmRestApi/resources/11.13.18.05/importActivities

{
"Name": "File Import through REST API",