Dedot exposes 3 high-level clients offering powerful API that abstracting over the complexities of on-making chain interactions (queries, transactions...) or sending raw JSON-RPC request to a blockchain nodes.
DedotClient: High-level Substrate client built on top of the new JSON-RPC API
LegacyClient: High-level Substrate client built on top of the legacy JSON-RPC API
JsonRpcClient: High-level JSON-RPC client to help making raw JSON-RPC requests or subscriptions seamlessly. Both DedotClient and LegacyClient are also a JsonRpcClient.
Both DedotClient and LegacyClient are both implementing theISubstrateClient<ChainApi, ApiEvent> interface, so they are sharing a list of common APIs of a client to interact with Subtrated-based blockchains.
DedotClient
DedotClient's high-level APIs are built on top of the new JSON-RPC API, beside implementing the common client APIs, DedotClient are also exposing access to JsonRpcGroup instances like ChainHead or ChainSpec.
import { DedotClient, WsProvider, PinnedBlock } from 'dedot';
import type { PolkadotApi } from '@dedot/chaintypes';
// Initialize providers & clients
const provider = new WsProvider('wss://rpc.polkadot.io');
const client = await DedotClient.new<PolkadotApi>(provider);
// Get current best runtime version
const currentBestRuntimeVersion = await client.getRuntimeVersion();
// Execute JSON-RPC methods
const metadata = await client.rpc.state_getMetadata();
// On-chain interactions
const balance = client.query.system.balance('<address>');
const transferTx = client.tx.balances.transferKeepAlive(<address>, 2_000_000_000_000n);
// Fetch ChainSpec information
const genesisHash = await client.chainSpec.genesisHash();
const chainProps = await client.chainSpec.properties();
// Access ChainHead data
const currentBestBlock = await client.chainHead.bestBlock();
const currentFinalizedBlock = await client.chainHead.finalizedBlock();
const finalizedRuntimeVersion = await client.chainHead.runtimeVersion();
const bestRuntimeVersion = await client.chainHead.bestRuntimeVersion();
// ...
// Listen to ChainHead events (best blocks, finalized block, ...)
const unsub = client.chainHead.on('bestBlock', (block: PinnedBlock, bestChainChanged: boolean) => {
console.log(`Current best block: ${block.number}, hash: ${block.hash}, bestChainChanged: ${bestChainChanged}`);
});
// Other ChainHead events available like:
// 'finalizedBlock': new best finalized block
// 'bestChainChanged': new best chain changed, a fork happened
// Or broadcast a raw transaction
const rawTxHex = '0x...';
const unsub = await client.chainHead.txBroadcaster.broadcastTx(rawTxHex);
LegacyClient
Similarly to DedotClient, LegacyClient is also another client that Dedot offers, but its high-level APIs are built on of the legacy JSON-RPC API.
import { LegacyClient, WsProvider } from 'dedot';
import type { PolkadotApi } from '@dedot/chaintypes';
// Initialize providers & clients
const provider = new WsProvider('wss://rpc.polkadot.io');
const client = await LegacyClient.new<PolkadotApi>(provider);
// Get current best runtime version
const currentBestRuntimeVersion = await client.getRuntimeVersion();
// Execute JSON-RPC methods
const metadata = await client.rpc.state_getMetadata();
// On-chain interactions
const balance = client.query.system.balance('<address>');
const transferTx = client.tx.balances.transferKeepAlive(<address>, 2_000_000_000_000n);
// Fetch ChainSpec information
const genesisHash = await client.rpc.chain_getBlockHash(0);
const chainProps = await client.rpc.system_properties();
// Access ChainHead data
const currentBestBlock = await client.rpc.chain_getBlock();
const currentFinalizedHash = await client.rpc.chain_getFinalizedHead();
const finalizedBlock = await client.rpc.chain_getBlock(currentFinalizedHash);
// ...
// Or broadcast a raw transaction
const rawTxHex = '0x...';
const txHash = await client.rpc.author_submitExtrinsic(rawTxHex);
// or
const unsub = await client.rpc.author_submitAndWatchExtrinsic(rawTxHex, (txStatus) => {});
JsonRpcClient
JsonRpcClient is a light-weight JSON-RPC client. Both DedotClient and LegacyClient are also extending JsonRpcClient, so one can access all the methods and props of a JsonRpcClient on DedotClient or LegacyClient. So unless for advanced interaction intensively via raw JSON-RPC, we recommend using high-level abstraction APIs on DedotClient or LegacyClient.
import { JsonRpcClient, WsProvider } from 'dedot';
import type { PolkadotApi } from '@dedot/chaintypes';
// Initialize providers & clients
const provider = new WsProvider('wss://rpc.polkadot.io');
const client = await JsonRpcClient.new<PolkadotApi>(provider);
// Get current best runtime version
console.log('Connection status:', client.status);
// Execute JSON-RPC methods
const metadata = await client.rpc.state_getMetadata();
const chain = await client.rpc.system_chain();
const nodeVersion = await client.rpc.system_version();
// Submit raw tx
const txHash = await client.rpc.author_submitExtrinsic('0x...');
Connection Status
Clients keep track of connection status, and it can be access via client.status with type ConnectionStatus
import { ConnectionStatus } from 'dedot';
// client: DedotClient, LegacyClient or JsonRpcClient
const status: ConnectionStatus = client.status;
There are 3 available statues:
connected: The client is connected to the network
disconnected: The client is disconnected from the network
reconnecting: The client is trying to reconnect to the network
Client Events
Clients will emit the following events in specific situations:
