Export Images from Neo4j to git

[dysbulic]

Images are imported into Neo4j using the isfdb:covers rake task. The structure is (Book)-[PUB]->(Version)-[CVR]->(Cover) where Cover.cid is a thing. The goal is to traverse the graph and produce an IPFS filesystem of the form: covers-#{isotime}/#{author}/#{title}/covers/#{isbn}.#{ext} where /#{title}/ is a git repository with a single commit of the cover images.

This could be the place to attempt a programmatic commit – generate a new commit for the addition of the images solely in IPFS and create it dynamically when requested by git.

Potentially, git allows the creation of new commits when retrieving from a remote. This would mean it isn't necessary to serialize the commit correctly to get a SHA1 object id for it.

Tasks include:

• Create a CBOR-DAG representing an empty repository.
• Check whether it is possible to retrieve commits whose oid is not known. Possibly by returning all 0s for the oid when asked to list what is available to fetch.
• Write the incoming directory structure to a root commit.
• Add that commit cid to the titles tree at the appropriate point.
• Abandon git.