@talismn/api

@talismn/api

A package for doing fast analysis across multiple DotSama chains at once.

At a high level, @talismn/api is a factory library which you can use to perform queries across many DotSama parachains. These queries are executed in parallel and their results are combined into a useful output.

This library can be made to fetch data via one of three connector types:

• TalismanConnect - our super lightweight RPC client designed to query potentially hundreds of parachains as fast and efficiently as possible ⚡
• PolkadotJs - the full featured RPC client from @paritytech
• [TODO] Lightclient - spin up a (light) node and talk straight to the parachain networks

By default this library uses the community-defined chain RPCs and lightclient chainspecs at TalismanSociety/chaindata, but can also be used with custom RPCs/chainspecs if needed.

The goals of this library are to:

• Allow developers to perform the same action across multiple chains (e.g. get account balances)
• Allow developers to discover chain capabilities (i.e. what pallets they may have)
• Provide developers with easy access to often-sought data located across multiple chains (all the balances!)

In the future, we would like to:

• Add parachain pallet discovery and introspection
• Add more aggregated information endpoints to accompany the balances endpoint (e.g. crowdloans, crowdloan contributions, bonded funds, etc)
• Decouple incoming calls to balances/subscribeBalances from outgoing RPC requests (add a cache which is shared between api calls, use RPC to fill cache rather than to directly respond to api request)

Usage

Please note: while we work towards a v1.0 release, the public interface is subject to change.

Import api

import Talisman from '@talismn/api'

note: Talisman is a singleton

Make a one-off call to balances

// Connect to the chain RPCs
await Talisman.connect({ chains: [0, 2, 2000] })

// Fetch balances
await Talisman.balances(['0x000...', '0x000...'])

// Will output an array of balances:
//
// [{
//   chainId: '0',
//   address: '0x000...',
//   token: 'DOT',
//
//   total: '10000000000000',
//   free: '10000000000000',
//   reserved: '0',
//   miscFrozen: '0',
//   feeFrozen: '0',
// }]

note: Talisman.connect is only required if not using subscriptions

Subscribe to balances

// Initialize the singleton
Talisman.init()

// Subscribe to balances
const unsubscribe = Talisman.subscribeBalances(
  [0, 2, 2000], // chains
  ['0x000...', '0x000...'], // addresses
  (balance) => console.log(balance)
)

// Will output all account balanaces once, then future balance changes as they happen:
//
// {
//   chainId: '0',
//   address: '0x000...',
//   token: 'DOT',
//
//   total: '10000000000000',
//   free: '10000000000000',
//   reserved: '0',
//   miscFrozen: '0',
//   feeFrozen: '0',
// }

// (later) Unsubscribe from future balances
unsubscribe()