Identifiers need to be created as per configuration in the repository

[marcolarosa]

extensions supported by the repo

• to inspect the repo and build a list of supported extensions
  • we will support https://ocfl.github.io/extensions/0004-hashed-n-tuple-storage-layout.html
  • we need to write an extension for handling arcp's to paths - @ peter sefton - you need to write an ocfl community extension and submit that describes this idea

library functionality to be implemented

• an arcp to path function in the library

  • use the value of the name as the root directory
  • hash the whole arcp to create the identifier

• n tuple hashing function - as defined by https://ocfl.github.io/extensions/0004-hashed-n-tuple-storage-layout.html

  • if there isn't already a JS library doing this then create this as a standalone library

• a function that takes an arcp path and returns a tupled path supporting extension defined above

  • rework idToPath to support the defined extensions

[ptsefton]

Trying to clarify the above.

We need two new idToPath functions that can be selected with config in the repo's extensions dir (any repo needs one of these, not multiples).

1. An implementation of the hashed-n-tuple storage layout algorithm id2NTuple(id) that is mentioned above. This will take an ID - any ID - hash it, and generate an n-tuple path looking in the repo config for the n-tuple parameters as described this extension.
2. An ARCP specific function arcpIDtopath(id) that will:

• Find the name part of the ARCP id and use it as the first directory under the storage root this can call the function in 1. above ${name}/${id2NTuple(id)}
• If it's not an ARCP ID then just return id2NTuple(id)

Note that the OCFL Object's inventory.id in the manifest should reference the original ID eg an arcp:// id (complete with the protocol and all the parts) or a URL

[ptsefton]

Above the issue should say:

hash the whole arcp (including protocol) and turn it into an n-tuple path to create then rest of the path (we are not creating an ID the ARCP is the identifier)