This is passed as the first argument to the callback to allow the user to see the progress
Create a new streaming indexer instance
Add data to the indexer
Finalize the pack and index
Get the packfile's hash
Free the indexer and its resources
Create a new indexer instance
Iterate over the objects in the packfile and extract the information
Write the index file to disk
Get the packfile's hash
Free the indexer and its resources