Network Interactions with SuiClient

The Sui TypeScript SDK provides a SuiClient class to connect to a network's JSON-RPC server. Use SuiClient for all JSON-RPC operations.

Connecting to a Sui network

To establish a connection to a network, import SuiClient from @mysten/sui.js/client and pass the relevant URL to the url parameter. The following example establishes a connection to Testnet and requests SUI from that network's faucet.

import { getFullnodeUrl, SuiClient } from '@mysten/sui.js/client';
 
// use getFullnodeUrl to define Devnet RPC location
const rpcUrl = getFullnodeUrl('devnet');
 
// create a client connected to devnet
const client = new SuiClient({ url: rpcUrl });
 
// get coins owned by an address
// replace <OWNER_ADDRESS> with actual address in the form of 0x123...
await client.getCoins({
	owner: '<OWNER_ADDRESS>',
});

The getFullnodeUrl helper in the previous code provides the URL for the specified network, useful during development. In a production application, however, you should use the Mainnet RPC address. The function supports the following values:

• localnet
• devnet
• testnet
• mainnet

For local development, you can run cargo run --bin sui-test-validator to spin up a local network with a local validator, a Full node, and a faucet server. Refer to the Local Network guide (opens in a new tab) for more information.

Manually calling unsupported RPC methods

You can use SuiClient to call any RPC method the node you're connectiong to exposes. Most RPC methods are built into SuiClient, but you can use call to leverage any methods available in the RPC.

import { getFullnodeUrl, SuiClient } from '@mysten/sui.js/client';
 
const client = new SuiClient({ url: getFullnodeUrl('devnet') });
 
// asynchronously call suix_getCommitteeInfo
const committeeInfo = await client.call('suix_getCommitteeInfo', []);

For a full list of available RPC methods, see the RPC documentation (opens in a new tab).

Subscribing to events with SuiClient

In addition to calling RPC methods, you can use SuiClient to subscribe to network events:

import { getFullnodeUrl, SuiClient } from '@mysten/sui.js/client';
 
const client = new SuiClient({
	url: getFullnodeUrl('testnet'),
});
 
// naming the function unsubscribe may seem counterintuitive here, but you call it later to unsubscribe from the event
const unsubscribe = await client.subscribeEvent({
	filter: {
		Sender: '<SENDER_ADDRESS>',
	},
	onMessage(event) {
		// handle subscription notification message here. This function is called once per subscription message.
	},
});
 
// later, to unsubscribe
await unsubscribe();

Subscribing to transactions with SuiClient

Similar to subscribing to events, the SuiClient also supports subscribing to transactions:

import { getFullnodeUrl, SuiClient } from '@mysten/sui.js/client';
 
const client = new SuiClient({
	url: getFullnodeUrl('testnet'),
});
 
const unsubscribe = await client.subscribeTransaction({
	filter: {
		FromAddress: '<SUI_ADDRESS>',
	},
	onMessage(event) {
		// This function is called once per transaction.
	},
});
 
// later, to unsubscribe:
await unsubscribe();

Customizing the transport

The SuiClient uses a Transport class to manage connections to the RPC node. The default SuiHTTPTransport makes both JSON RPC requests, as well as websocket requests for subscriptions. You can construct a custom transport instance if you need to pass any custom options, such as headers or timeout values.

import { getFullnodeUrl, SuiClient, SuiHTTPTransport } from '@mysten/sui.js/client';
 
const client = new SuiClient({
	transport: new SuiHTTPTransport({
		url: 'https://my-custom-node.com/rpc',
		websocket: {
			reconnectTimeout: 1000,
			url: 'https://my-custom-node.com/websockets',
		},
		rpc: {
			headers: {
				'x-custom-header': 'custom value',
			},
		},
	}),
});

Pagination

SuiClient exposes a number of RPC methods that return paginated results. These methods return a result object with 3 fields:

• data: The list of results for the current page
• nextCursor: a cursor pointing to the next page of results
• hasNextPage: a boolean indicating whether there are more pages of results

Some APIs also accept an order option that can be set to either ascending or descending to change the order in which the results are returned.

You can pass the nextCursor to the cursor option of the RPC method to retrieve the next page, along with a limit to specify the page size:

const page1 = await client.getCheckpoints({
	limit: 10,
});
 
const page2 =
	page1.hasNextPage &&
	client.getCheckpoints({
		cursor: page1.nextCursor,
		limit: 10,
	});