Client library to connect your app with forge powered blockchain node, all requests are sent over http/https, can be used in both Node.js and browser environment.

A GraphQLClient instance mainly supports 5 groups of methods that saves you time when read/write data from/to blockchain.

• queries: query block/transaction/account/asset/chain/node data form the blockchain
• mutations: send transaction to the blockchain, sendTx, all transactions should be signed before sending out to the blockchain
• subscriptions: listen to changes of any data on the blockchain
• senders: shortcut methods that takes a wallet and a tx object, then do the signing, and sending
• encoders: shortcut methods that takes a wallet and a tx object, encode the transaction for later signing, used internally by senders

Table of Contents

• Install
• Usage
• Subscriptions
• Subpath Exports
• Migration Notes
• Examples
• Debugging
• Documentation

Install

npm i @ocap/client -S
# OR
bun install @ocap/client

Usage

const Mcrypto = require('@ocap/mcrypto');
const GraphQLClient = require('@ocap/client');
const { fromRandom, WalletType } = require('@ocap/wallet');
const { hexToBytes } = require('@ocap/util');

const client = new GraphQLClient('http://localhost:8210/api');
console.log({
  queries: client.getQueries(),
  subscriptions: client.getSubscriptions(),
  mutations: client.getMutations(),
  senders: client.getTxSendMethods(),
  encoders: client.getTxEncodeMethods(),
});

(async () => {
  // Query chain state data
  const chainInfo = await client.getChainInfo();
  const forgeState = await client.getForgeState();
  const block = await client.getBlock({ height: 2 });
  console.log('getChainInfo', chainInfo);
  console.log('getForgeState', forgeState);
  console.log('getBlock', block);

  // Send transaction
  const wallet = fromRandom(
    WalletType({
      role: Mcrypto.types.RoleType.ROLE_ACCOUNT,
      pk: Mcrypto.types.KeyType.SECP256K1,
      hash: Mcrypto.types.HashType.SHA3,
    })
  );
  const hash = await client.declare({
    moniker: 'username',
    wallet,
  });
  console.log(hash);
})();

Subscriptions

subscribe / unsubscribe pull in @arcblock/ws (phoenix + ws), which is ~68 KB after minification. To keep the default browser bundle small, the websocket client is shipped as an optional install:

• Node / @ocap/client/legacy — auto-installed by the constructor, call client.subscribe(topic, cb) directly.
• Browser — the default entry's subscribe / unsubscribe throw until you install them explicitly:

import Client from '@ocap/client';
import { install as installSubscribe } from '@ocap/client/subscribe';

const client = new Client(endpoint);
installSubscribe(client);
client.subscribe('tx.create', (tx) => console.log(tx));

Apps that never need subscriptions pay zero bytes for this code path.

Subpath Exports

The package ships three subpath entries in addition to the default:

| Entry | Purpose | Bundle cost | | ------------------------ | ------------------------------------------------------------------------------- | ------------------------------------ | | @ocap/client | Full CBOR-only client (queries, mutations, senders, encoders) | ~503 KB minified | | @ocap/client/encode | Tree-shakable encodeTx / decodeTx helpers — no GraphQL, no websockets | ~179 KB minified | | @ocap/client/subscribe | Optional websocket installer, see Subscriptions | ~68 KB minified | | @ocap/client/legacy | Protobuf wire-encoding client for chain nodes that still decode the legacy path | pulls in google-protobuf (~300 KB) |

All subpaths require a bundler that honors the exports field (webpack 5, Vite, esbuild, Rollup, Bun). For webpack 4 you must enable resolve.exportsFields.

Migration Notes

• options.encoding — the default entry is CBOR-only. Passing new Client(endpoint, true, { encoding: 'protobuf' }) throws immediately. Import from @ocap/client/legacy when you need the protobuf path.
• Browser subscribe / unsubscribe — now throw SUBSCRIBE_NOT_INSTALLED by default; see Subscriptions. Node and /legacy behavior is unchanged.
• Client-side factory validation — createAssetFactory no longer runs isValidFactory before sending. Invalid factories surface as a chain-side RPC error instead of a local throw.
• setGasPayer parsing — the GraphQL AST parse was replaced with a bounded regex. Queries with $tx variables (instead of the literal form the built-in sendTx uses) will silently skip the gas-payer headers.

Examples

• Declare identify on the blockchain
• Get free token for newly created account
• Transfer assets between 2 accounts
• Transfer tokens between 2 accounts
• Exchange asset and token between 2 newly created accounts
• Create/update asset on the blockchain
• Consume newly create asset
• Stake for the connected node

Debugging

• If you are in Node.js: DEBUG=@ocap/client node script.js
• If you are in browser: localStorage.setItem('DEBUG', '@ocap/client')

Documentation

• Query arguments and response structure can be found here: QUERIES.md
• Complete method list can be found here: README.md