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Hyperdrive

stable
Hyperdrive is a secure, real-time distributed file system designed for easy P2P file sharing. We use it extensively inside Holepunch; apps like Keet are distributed to users as Hyperdrives, as is the Holepunch platform itself.

Installation

Install with npm:
npm install hyperdrive

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.

Properties

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.key

The public key of the Hypercore backing the drive.

drive.discoveryKey

The hash of the public key of the Hypercore backing the drive. It 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.version

The number that indicates how many modifications were made, is useful as a version identifier.

drive.supportsMetadata

Boolean indicating if the drive handles or not metadata. Always true.

Methods

await drive.ready()

Waits until the 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 data structures.

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)

Returns the blob at path in the drive. If no blob exists, returns null.
It also returns null for symbolic links.

const entry = await drive.entry(path)

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
}
}

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.
The underlying blob is not deleted, only the reference in the file structure.

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:
Property
Description
Type
Default
diff
Returned cleared bytes object is null unless you enable this
Boolean
false

const cleared = await drive.clearAll([options])

Deletes all the blobs from storage to free up space, similar to how drive.clear() works.
options include:
Property
Description
Type
Default
diff
Returned cleared bytes object is null unless you enable this
Boolean
false

await drive.purge()

Purge both cores (db and blobs) from your storage, completely removing all the drive's data.
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 mutating 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:
Property
Description
Type
Default
recursive
whether to descend into all subfolders or not
Boolean
true

const stream = drive.readdir(folder)

Returns a stream of all subpaths of entries in the drive stored at paths prefixed by folder.

const stream = await drive.entries([options])

Returns a read stream of entries in the drive.
options are the same as the options to Hyperbee().createReadStream(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)
}
current and previous are the snapshots that are auto-closed before next value.
Do not close those snapshots yourself because they're used internally, let them be auto-closed.
Methods:
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:
Property
Description
Type
Default
executable
whether the blob is executable or not
Boolean
true
metadata
Extended file information i.e., arbitrary JSON value
Object
null

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 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.corestore.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.corestore.replicate(isInitiatorOrStream)

Usage example:
const swarm = new Hyperswarm()
const done = drive.corestore.findingPeers()
swarm.on('connection', (socket) => drive.corestore.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.corestore.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