Subscribe to Updates

Subscribe to any updates in blockchain database, including contract events.

When you may need it?

Whenever you need to improve UI responsiveness or want to receive updates on your backend as they appear - you may use websocket subscriptions.

Usage

Account updates

const accountSubscription = await TonClient.default.net.subscribe_collection({
    collection: "accounts",
    filter: { id: { eq: address } },
    result: "balance",
}, (params, responseType) => {
    if (responseType === ResponseType.Custom) {
        console.log("Account has updated. Current balance is ", parseInt(params.result.balance));
    }
});

Account messages

const messageSubscription = await TonClient.default.net.subscribe_collection({
    collection: "messages",
    filter: {
        src: { eq: address },
        OR: {
            dst: { eq: address },
        }
    },
    result: "boc",
}, async (params, responseType) => {
    try {
        if (responseType === ResponseType.Custom) {
            const decoded = (await TonClient.default.abi.decode_message({
                abi: abiContract(your-contract-abi),
                message: params.result.boc,
            }));
            switch (decoded.body_type) {
            case MessageBodyType.Input:
                console.log(`External inbound message, function "${decoded.name}", parameters: `, JSON.stringify(decoded.value));
                break;
            case MessageBodyType.Output:
                console.log(`External outbound message, function "${decoded.name}", result`, JSON.stringify(decoded.value));
                break;
            case MessageBodyType.Event:
                console.log(`External outbound message, event "${decoded.name}", parameters`, JSON.stringify(decoded.value));
                break;
            }
        }
    } catch (err) {
        console.log('>>>', err);
    }
});

See this sample to understand how to use subscribe_collection function:

https://github.com/everx-labs/sdk-samples/tree/master/core-examples/node-js/listen-and-decode