contentfs

contentfs (Content Addressable Filesystem)

A filesystem is a tree of names that correspond to points of data.

Content addressablility is when content is referred to by a consistent hash of the content rather than a human readable name.

contenfs is a content addressable filesystem. It stores a map of names to content addresses. This meta info is itself stored in a content addressable manor as well. This means that every "directory" has a hash that will change whenever any of the content in the tree is changed.

This structure is very useful for syncing representations of filesystems and other similar human readable structures and syncing them around. It is not very useful for syncing and merging changes inside of individual files.

contentfs builds on top of lucass, an abstraction for content addressable storage. This allows contentfs to easily map on top of all sorts of underlying storage systems (inmemory, fs, S3, IndexDB, blockchain, etc). The only catch is that the hashing system must be consistent between the two implementations (many implementations allow their hashing to be configured).

let inmem = require('lucass/inmemory')
let localstore = inmem()
let remotestore = inmem()
let store = await contentfs.from(__dirname, localstore, remotestore)
await store.set('/filename.txt', Buffer.from('asdf'))
// local store has its tree updated and content stored, remote does not.
let [rootNode, hashes] = await store.push()
// remote was pushed `hashes`
await setRemoteRootNode(rootNode) // tell remote storage to move to the new root node