@totemsdk/chain-provider

Unified abstraction over all chain data sources.

A strategy pattern for chain access. Any Totem SDK tool that needs on-chain data accepts a ChainStateProvider. Swap implementations without changing application code.

Install

npm install @totemsdk/chain-provider

What's inside

The interface

interface ChainStateProvider {
  getCoins(query: CoinQuery): Promise<Coin[]>;
  getCoin(id: string): Promise<Coin | null>;
  getMMRProof(coinId: string): Promise<MMRProof>;
  getChainTip(): Promise<ChainTip>;
  getToken(id: string): Promise<Token | null>;
  searchTokens(query: string): Promise<Token[]>;
  broadcastTxPoW(hex: string): Promise<BroadcastResult>;
}

Concrete implementations

| Class | Connects to | |-------|------------| | HostedProvider | Axia / MEG hosted API (requires project credentials) | | PureMinimaRpcProvider | A local or self-hosted PureMinima node directly | | LookupNodeProvider | A personal lookup node over Hyperswarm DHT | | CompositeProvider | Fans out across multiple providers with fallback logic |

Five other packages (omnia, statechain, lookup-node, lookup-client, chain-provider itself) accept ChainStateProvider — this is the pivot point between the upper SDK and chain data.

Usage

Hosted provider (fastest setup)

import { HostedProvider } from '@totemsdk/chain-provider';

const provider = new HostedProvider({
  baseUrl: 'https://api.axia.to',
  projectId: 'your-project-id',
  projectSecret: process.env.AXIA_SECRET,
});

const tip  = await provider.getChainTip();
const coins = await provider.getCoins({ address: 'Mx...' });

Self-hosted node

import { PureMinimaRpcProvider } from '@totemsdk/chain-provider';

const provider = new PureMinimaRpcProvider({
  nodeUrl: 'http://localhost:9005',
});

Composite with fallback

import { CompositeProvider, HostedProvider, PureMinimaRpcProvider } from '@totemsdk/chain-provider';

const provider = new CompositeProvider([
  new PureMinimaRpcProvider({ nodeUrl: 'http://localhost:9005' }),
  new HostedProvider({ baseUrl: 'https://api.axia.to', projectId: '...' }),
]);
// Queries hit the first provider; fallback to the second on error

Personal lookup node

import { LookupNodeProvider } from '@totemsdk/chain-provider';

const provider = new LookupNodeProvider({
  publicKey: '...your-lookup-node-pubkey...',
});

See also

• @totemsdk/pureminima-rpc — the RPC client used by PureMinimaRpcProvider
• @totemsdk/lookup-client — LookupClientProvider implementation
• @totemsdk/node — Node.js MinimaProvider
• @totemsdk/omnia — uses ChainStateProvider for coin queries