content-addressable-blob-store

Streamable content addressable blob object store that is streams2 and implements the blob store interface on top of the fs module.

Conforms to the abstract-blob-store API and passes it's test suite.

npm install content-addressable-blob-store

Usage

var blobs = require('content-addressable-blob-store')
var store = blobs('./data')

var w = store.createWriteStream()

w.write('hello ')
w.write('world\n')

w.end(function () {
  console.log('blob written: '+w.key)
  store.createReadStream(w).pipe(process.stdout)
})

API

var store = blobs(opts)

Creates a new instance. Opts should have a path property to where the blobs should live on the fs. The directory will be created if it doesn't exist. If not supplied it will default to path.join(process.cwd(), 'blobs')

You can also specify a node crypto module hashing algorithm to use using the algo key in options. The default is sha256. If you pass a string instead of an options map it will be used as the path as well.

The tmpdir option can be used to specify the directory where files are stored temporarily during writing. The default is os.tmpdir().

var readStream = store.createReadStream(opts)

Open a read stream to a blob. opts must have a key key with the hash of the blob you want to read. opts can optionally contain a start or end key if you only want part of the blob.

var writeStream = store.createWriteStream([cb])

Add a new blob to the store. Use writeStream.key to get the hash after the finish event has fired or add a callback which will be called with callback(err, metadata).

store.exists(metadata, cb)

Check if an blob exists in the blob store. metadata must have a key property. Callback is called with callback(err, exists)

store.remove(metadata, [cb])

Remove a blob from the store. metadata must have a key property. Callback is called with callback(err, wasDeleted)

store.resolve(metadata, cb)

Check if an blob exists in the blob store and return its path and stat object. metadata must have a key property. Callback is called with callback(err, path, stat) where path is the path string to the file on disk and stat is an instance of fs.Stats. If the key does does not exist in the store, path will be false and stat will be null.

License

MIT