polkadot-api
Features
- Light client first: built on top of the new JSON-RPC spec to fully leverage the potential of light-clients (i.e: smoldot).
- Delightful TypeScript support with types and docs generated from on-chain metadata.
- First class support for storage reads, constants, transactions, events and runtime-calls.
- Performant and lightweight: ships with multiple subpaths, so dApps don't bundle unnecessary assets.
- Uses native BigInt, instead of large BigNumber libraries
- Leverages dynamic imports to favour faster loading times.
- Promise-based and Observable-based APIs: use the one that best suit your needs and/or coding style.
- Use signers from your browser extension, or from a private key.
- Easy integration with PJS-based extensions.
... and a lot lot more.
Overview
smoldot.ts
import { startFromWorker } from "polkadot-api/smoldot/from-worker"
import SmWorker from "polkadot-api/smoldot/worker?worker"
// Starting smoldot on a Worker (strongly recommended)
export const smoldot = startFromWorker(new SmWorker())
// Alternatively, we could have smoldot running on the main-thread, e.g:
// import { start } from "polkadot-api/smoldot"
// export const smoldot = start()
main.ts
import { createClient } from "polkadot-api"
import { getSmProvider } from "polkadot-api/sm-provider"
import { polkadotTypes } from "@polkadot-api/descriptors"
import { smoldot } from "./smoldot"
// dynamically importing the chainSpec improves the performance of your dApp
const smoldotRelayChain = import("polkadot-api/chains/polkadot").then(
({ chainSpec }) => smoldot.addChain({ chainSpec }),
)
// getting a `JsonRpcProvider` from a `smoldot` chain.
const jsonRpcProvider = getSmProvider(smoldotRelayChain)
// we could also create a `JsonRpcProvider` from a WS connection, eg:
// const jsonRpcProvider = WsProvider("wss://some-rpc-endpoint.io")
const polkadotClient = createClient(jsonRpcProvider)
// logging blocks as they get finalized
polkadotClient.finalizedBlock$.subscribe((block) => {
console.log(`#${block.number} - ${block.hash} - parentHash: ${block.parent}`)
})
// pulling the latest finalized block
const block = await polkadotClient.getFinalizedBlock()
// obtaining a delightfully typed interface from the descriptors
// previously generated from the metadata
const polkadotApi = polkadotClient.getTypedApi(polkadotTypes)
// presenting the transferrable amount of a given account
const {
data: { free, frozen },
} = await polkadotApi.query.System.Account.getValue(
"15oF4uVJwmo4TdGW7VfQxNLavjCXviqxT9S1MgbjMNHr6Sp5",
)
console.log(`Transferrable amount: ${free - frozen}`)
Documentation
Browse our latest docs here!
Announcement: Transfer of Ownership
As of 2024-02-01, the original owner and maintainer of the Polkadot-API project, Parity Technologies, has officially transferred ownership of the project to me, Josep M Sobrepere. Read more about this transfer here.
