...

4. Trigger Boxalino Process

If you did all 3 prior steps (so your data are loaded in your own BigQuery DataSet), then call the Sync Request.If you only did the first step and want to send your files directly, then call first the Load Request for each of your files.

Whether you called the Load Process first or not before, you need then to call the then call the Sync Request (once for all the files).