Awesome
Hyperdrive
See API docs at docs.holepunch.to
Hyperdrive is a secure, real-time distributed file system
Install
npm install hyperdrive
Usage
const Hyperdrive = require('hyperdrive')
const Corestore = require('corestore')
const store = new Corestore('./storage')
const drive = new Hyperdrive(store)
await drive.put('/blob.txt', Buffer.from('example'))
await drive.put('/images/logo.png', Buffer.from('..'))
await drive.put('/images/old-logo.png', Buffer.from('..'))
const buffer = await drive.get('/blob.txt')
console.log(buffer) // => <Buffer ..> "example"
const entry = await drive.entry('/blob.txt')
console.log(entry) // => { seq, key, value: { executable, linkname, blob, metadata } }
await drive.del('/images/old-logo.png')
await drive.symlink('/images/logo.shortcut', '/images/logo.png')
for await (const file of drive.list('/images')) {
console.log('list', file) // => { key, value }
}
const rs = drive.createReadStream('/blob.txt')
for await (const chunk of rs) {
console.log('rs', chunk) // => <Buffer ..>
}
const ws = drive.createWriteStream('/blob.txt')
ws.write('new example')
ws.end()
ws.once('close', () => console.log('file saved'))
API
const drive = new Hyperdrive(store, [key])
Creates a new Hyperdrive instance. store
must be an instance of Corestore
.
By default it uses the core at { name: 'db' }
from store
, unless you set the public key
.
await drive.ready()
Waits until internal state is loaded.
Use it once before reading synchronous properties like drive.discoveryKey
, unless you called any of the other APIs.
await drive.close()
Fully close this drive, including its underlying Hypercore backed datastructures.
drive.corestore
The Corestore instance used as storage.
drive.db
The underlying Hyperbee backing the drive file structure.
drive.core
The Hypercore used for drive.db
.
drive.id
String containing the id (z-base-32 of the public key) identifying this drive.
drive.key
The public key of the Hypercore backing the drive.
drive.discoveryKey
The hash of the public key of the Hypercore backing the drive.
Can be used as a topic
to seed the drive using Hyperswarm.
drive.contentKey
The public key of the Hyperblobs instance holding blobs associated with entries in the drive.
drive.writable
Boolean indicating if we can write or delete data in this drive.
drive.readable
Boolean indicating if we can read from this drive. After closing the drive this will be false
.
drive.version
Number that indicates how many modifications were made, useful as a version identifier.
drive.supportsMetadata
Boolean indicating if the drive handles or not metadata. Always true
.
await drive.put(path, buffer, [options])
Creates a file at path
in the drive. options
are the same as in createWriteStream
.
const buffer = await drive.get(path, [options])
Returns the blob at path
in the drive. If no blob exists, returns null
.
It also returns null
for symbolic links.
options
include:
{
wait: true, // Wait for block to be downloaded
timeout: 0 // Wait at max some milliseconds (0 means no timeout)
}
const entry = await drive.entry(path, [options])
Returns the entry at path
in the drive. It looks like this:
{
seq: Number,
key: String,
value: {
executable: Boolean, // Whether the blob at path is an executable
linkname: null, // If entry not symlink, otherwise a string to the entry this links to
blob: { // Hyperblobs id that can be used to fetch the blob associated with this entry
blockOffset: Number,
blockLength: Number,
byteOffset: Number,
byteLength: Number
},
metadata: null
}
}
options
include:
{
follow: false, // Follow symlinks, 16 max or throws an error
wait: true, // Wait for block to be downloaded
timeout: 0 // Wait at max some milliseconds (0 means no timeout)
}
const exists = await drive.exists(path)
Returns true
if the entry at path
does exists, otherwise false
.
await drive.del(path)
Deletes the file at path
from the drive.
const comparison = drive.compare(entryA, entryB)
Returns 0
if entries are the same, 1
if entryA
is older, and -1
if entryB
is older.
const cleared = await drive.clear(path, [options])
Deletes the blob from storage to free up space, but the file structure reference is kept.
options
include:
{
diff: false // Returned `cleared` bytes object is null unless you enable this
}
const cleared = await drive.clearAll([options])
Deletes all the blobs from storage to free up space, similar to how drive.clear()
works.
options
include:
{
diff: false // Returned `cleared` bytes object is null unless you enable this
}
await drive.truncate(version, [options] })
Truncates the Hyperdrive to a previous version (both the file-structure reference and the blobs).
A blobs: <length>
option can be passed in if you know the corresponding blobs length, but it is recommended to let the method figure it out for you.
await drive.purge()
Purge both cores (db and blobs) from your storage, completely removing all the drive's data.
await drive.symlink(path, linkname)
Creates an entry in drive at path
that points to the entry at linkname
.
If a blob entry currently exists at path
then it will get overwritten and drive.get(key)
will return null
, while drive.entry(key)
will return the entry with symlink information.
const batch = drive.batch()
Useful for atomically mutate the drive, has the same interface as Hyperdrive.
await batch.flush()
Commit a batch of mutations to the underlying drive.
const stream = drive.list(folder, [options])
Returns a stream of all entries in the drive at paths prefixed with folder
.
options
include:
{
recursive: true | false // Whether to descend into all subfolders or not,
ignore: String || Array // Ignore files and folders by name,
wait: true, // Wait for block to be downloaded.
}
const stream = drive.readdir(folder, [options])
Returns a stream of all subpaths of entries in drive stored at paths prefixed by folder
.
options
include:
{
wait: true, // Wait for block to be downloaded
}
const stream = await drive.entries([range], [options])
Returns a read stream of entries in the drive.
options
are the same as Hyperbee().createReadStream([range], [options])
.
const mirror = drive.mirror(out, [options])
Efficiently mirror this drive into another. Returns a MirrorDrive
instance constructed with options
.
Call await mirror.done()
to wait for the mirroring to finish.
const watcher = drive.watch([folder])
Returns an iterator that listens on folder
to yield changes, by default on /
.
Usage example:
for await (const [current, previous] of watcher) {
console.log(current.version)
console.log(previous.version)
}
Those current
and previous
are snapshots that are auto-closed before next value.
Don't close those snapshots yourself because they're used internally, let them be auto-closed.
await watcher.ready()
Waits until the watcher is loaded and detecting changes.
await watcher.destroy()
Stops the watcher. You could also stop it by using break
in the loop.
const rs = drive.createReadStream(path, [options])
Returns a stream to read out the blob stored in the drive at path
.
options
include:
{
start: Number, // `start` and `end` are inclusive
end: Number,
length: Number, // `length` overrides `end`, they're not meant to be used together
wait: true, // Wait for blocks to be downloaded
timeout: 0 // Wait at max some milliseconds (0 means no timeout)
}
const ws = drive.createWriteStream(path, [options])
Stream a blob into the drive at path
.
options
include:
{
executable: Boolean,
metadata: null // Extended file information i.e. arbitrary JSON value
}
await drive.download(folder, [options])
Downloads the blobs corresponding to all entries in the drive at paths prefixed with folder
.
options
are the same as those for drive.list(folder, [options])
.
const snapshot = drive.checkout(version)
Get a read-only snapshot of a previous version.
const stream = drive.diff(version, folder, [options])
Efficiently create a stream of the shallow changes to folder
between version
and drive.version
.
Each entry is sorted by key and looks like this:
{
left: Object, // Entry in folder at drive.version for some path
right: Object, // Entry in folder at drive.checkout(version) for some path
}
If an entry exists in drive.version
of the folder
but not in version
, then left
is set and right
will be null
, and vice versa.
await drive.downloadDiff(version, folder, [options])
Downloads all the blobs in folder
corresponding to entries in drive.checkout(version)
that are not in drive.version
.
In other words, downloads all the blobs added to folder
up to version
of the drive.
await drive.downloadRange(dbRanges, blobRanges)
Downloads the entries and blobs stored in the ranges dbRanges
and blobRanges
.
const done = drive.findingPeers()
Indicate to Hyperdrive that you're finding peers in the background, requests will be on hold until this is done.
Call done()
when your current discovery iteration is done, i.e. after swarm.flush()
finishes.
const stream = drive.replicate(isInitiatorOrStream)
Usage example:
const swarm = new Hyperswarm()
const done = drive.findingPeers()
swarm.on('connection', (socket) => drive.replicate(socket))
swarm.join(drive.discoveryKey)
swarm.flush().then(done, done)
See more about how replicate works at corestore.replicate.
const updated = await drive.update([options])
Waits for initial proof of the new drive version until all findingPeers
are done.
options
include:
{
wait: false
}
Use drive.findingPeers()
or { wait: true }
to make await drive.update()
blocking.
const blobs = await drive.getBlobs()
Returns the Hyperblobs instance storing the blobs indexed by drive entries.
await drive.put('/file.txt', Buffer.from('hi'))
const buffer1 = await drive.get('/file.txt')
const blobs = await drive.getBlobs()
const entry = await drive.entry('/file.txt')
const buffer2 = await blobs.get(entry.value.blob)
// => buffer1 and buffer2 are equals
const blobsLength = await drive.getBlobsLength(checkout)
Returns the length of the Hyperblobs instance at the time of the specified Hyperdrive version (defaults to the current version).
License
Apache-2.0