@dhub/client

Standalone DHub RPC client

npm install @dhub/client

Usage

const DHubClient = require('@dhub/client')

const client = new DHubClient() // connect to the DHub server

const basestore = client.basestore() // make a basestore

const feed = basestore.get(someDDatabaseKey) // make a ddatabase

await feed.get(42) // get some data from the ddatabase

API

const client = new DHubClient([options])

Make a new DHub RPC client. Options include:

{
  host: 'dhub', // the ipc name of the running server
                      // defaults to dhub
  port                // a TCP port to connect to
}

If port is specified, or host and port are both specified, then the client will attempt to connect over TCP.

If you only provide a host option, then it will be considered a Unix socket name.

await DHubClient.serverReady([host])

Static method to wait for the local IPC server to be up and running.

status = await client.status([callback])

Get status of the local daemon. Includes stuff like API version etc.

await client.close([callback])

Fully close the client. Cancels all inflight requests.

await client.ready([callback])

Wait for the client to have fully connected and loaded initial data.

basestore = client.basestore([namespace])

Make a new remote basestore. Optionally you can pass a specific namespace to load a specific basestore. If you do not pass a namespace a random one is generated for you.

client.network

The remote basestore network instance.

client.replicate(base)

A one-line replication function for RemoteDDatabases (see below for details).

Remote Basestore

The remote basestore instances has an API that mimicks the normal basestore API.

feed = basestore.get([key])

Make a new remote ddatabase instance. If you pass a key that specific feed is loaded, if not a new one is made.

feed = basestore.default()

Get the "default" feed for this basestore, which is derived from the namespace.

feed.name

The name (namespace) of this basestore.

async feed.close([callback])

Close the basestore. Closes all feeds made in this basestore.

Remote Networker

The remote networker instance has an API that mimicks the normal basestore networker API.

await network.ready([callback])

Make sure all the peer state is loaded locally. client.ready calls this for you. Note you do not have to call this before using any of the apis, this just makes sure network.peers is populated.

networks.peers

A list of peers we are connected to.

network.on('peer-add', peer)

Emitted when a peer is added.

network.on('peer-remove', peer)

Emitted when a peer is removed.

await network.configure(discoveryKey | RemoteDDatabase, options)

Configure the network for this specific discovery key or RemoteDDatabase. Options include:

{
  lookup: true, // should we find peers?
  announce: true, // should we announce ourself as a peer?
  flush: true // wait for the full swarm flush before returning?
  remember: false // persist this configuration so it stays around after we close our session?
}

const ext = network.registerExtension(name, { encoding, onmessage, onerror })

Register a network protocol extension.

Remote Feed

The remote feed instances has an API that mimicks the normal DDatabase API.

feed.key

The feed public key

feed.discoveryKey

The feed discovery key.

feed.writable

Boolean indicating if this feed is writable.

await feed.ready([callback])

Wait for the key, discoveryKey, writability, initial peers to be loaded.

const block = await feed.get(index, [options], [callback])

Get a block of data from the feed.

Options include:

{
  ifAvailable: true,
  wait: false,
  onwait () { ... }
}

See the DDatabase docs for more info on these options.

Note if you don't await the promise straight away you can use it to to cancel the operation, later using feed.cancel

const p = feed.get(42)
// ... cancel the get
feed.cancel(p)
await p // Was cancelled

feed.cancel(p)

Cancel a get

await feed.has(index, [callback])

Check if the feed has a specific block

await feed.download(start, end, [callback])

Select a range to be downloaded. Similarly to feed.get you can use the promise itself to cancel a download using feed.undownload(p)

feed.undownload(p)

Stop downloading a range.

await feed.update([options], [callback])

Fetch an update for the feed.

Options include:

{
  minLength: ..., // some min length to update to
  ifAvailable: true,
  hash: true
}

See the DDatabase docs for more info on these options.

await feed.append(blockOrArrayOfBlocks, [callback])

Append a block or array of blocks to the ddatabase

feed.peers

A list of peers this feed is connected to.

feed.on('peer-add', peer)

Emitted when a peer is added.

feed.on('peer-remove', peer)

Emitted when a peer is removed.

feed.on('append')

Emitted when the feed is appended to, either locally or remotely.

feed.on('download', seq, data)

Emitted when a block is downloaded. data is a pseudo-buffer with {length, byteLength} but no buffer content.

feed.on('upload', seq, data)

Emitted when a block is uploaded. data is a pseudo-buffer with {length, byteLength} but no buffer content.

Replicator

DHub also includes a simple replication function for RemoteDDatabases that does two things:

1. It first configures the network (client.network.configure(base, { announce: true, lookup: true }))
2. Then it does a base.update({ ifAvailable: true }) to try to fetch the latest length from the network.

This saves a bit of time when swarming a RemoteDDatabase.

await replicate(base)

Quickly connect a RemoteDDatabase to the DSwarm network.

License

MIT