Upsert data to Business Object in batch upload

Summary

Unable to create batch request(upsert) for custom business objects

Content

I need to perform insert or update operation based on the user input received while processing batch upload. I have the prototype working for single request but need multiple records to be inserted in a single user action. I have created a business object function to update/insert a record to a business object. When I am using the newly created POST endpoint to update/insert the entry to the BO, it is working fine for single request. However I am unable to create a batch request for the same.