chain_getFinalizedHead - Midnight

Example code for the chain_getFinalizedHead JSON-RPC method. Complete guide on how to use chain_getFinalizedHead JSON-RPC in GetBlock Web3 documentation.

This method returns the hash of the latest finalized block. Finalized blocks are confirmed by GRANDPA and cannot be reverted. The spelling variant chain_getFinalisedHead is also supported and returns the same value.

Parameters

None

Request Example

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "chain_getFinalizedHead",
    "params": [],
    "id": "getblock.io"
}'

import requests
import json

url = "https://go.getblock.io/<ACCESS-TOKEN>/"

payload = json.dumps({
    "jsonrpc": "2.0",
    "method": "chain_getFinalizedHead",
    "params": [],
    "id": "getblock.io"
})

headers = {
    'Content-Type': 'application/json'
}

response = requests.post(url, headers=headers, data=payload)
print(response.text)

use reqwest::Client;
use serde_json::json;

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();

    let payload = json!({
        "jsonrpc": "2.0",
        "method": "chain_getFinalizedHead",
        "params": [],
        "id": "getblock.io"
});

    let response = client
        .post("https://go.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&payload)
        .send()
        .await?;

    let result: serde_json::Value = response.json().await?;
    println!("{:#?}", result);

    Ok(())
}

Response Example

{
    "jsonrpc": "2.0",
    "result": "0xb26f48fdafcedfd991a681e9c0e910e60c4d7beac3c9b18d4ff834e82d63b3d8",
    "id": "getblock.io"
}

Response Parameters

Field

Type

Description

result

string

Hash of the latest finalized block

Use Cases

Finality-aware indexers that only process irreversible blocks
Computing safe confirmation depth
Bridges and exchanges that wait for finality before crediting deposits

Error Handling

Status Code

Error Message

Cause

403

Forbidden

Missing or invalid <ACCESS-TOKEN>

-32602

Invalid params

Request parameters are missing or malformed

-32601

Method not found

The method is not enabled on this node or has been deprecated

429

Too Many Requests

Rate limit exceeded for your plan

SDK Integration

import { ApiPromise, WsProvider } from '@polkadot/api';

const wsProvider = new WsProvider('wss://go.getblock.io/<ACCESS-TOKEN>/');
const api = await ApiPromise.create({ provider: wsProvider });

// Call via the typed API:
const result = await api.rpc.chain.getFinalizedHead();
console.log(result.toJSON());

// Or call the raw JSON-RPC method:
const raw = await api.rpc.rpc.methods();
// const raw = await (api as any)._rpcCore.provider.send('chain_getFinalizedHead', []);

from substrateinterface import SubstrateInterface

substrate = SubstrateInterface(url='wss://go.getblock.io/<ACCESS-TOKEN>/')

# Generic RPC call:
result = substrate.rpc_request('chain_getFinalizedHead', [])
print(result)

Previousauthor_pendingExtrinsics - Midnight Nextoffchain_localStorageSet - Midnight

Last updated 1 month ago

Was this helpful?