chain_getBlock

Description

Returns complete block information, including the header and SCALE-encoded extrinsics. Supplying a block hash lets you fetch historical blocks deterministically; omitting the parameter yields the latest block known to the node.

Parameters

Parameter	Type	Required	Description
blockHash	string	No	Hex-encoded block hash. If omitted, the latest block is returned

Returns

Field	Type	Description
block.header	object	Block header (parent hash, number, state root, extrinsics root, digest)
block.extrinsics	array	Array of SCALE-encoded extrinsic payloads
justifications	array | null	Finality justifications, if present

Request Example

{
  "jsonrpc": "2.0",
  "method": "chain_getBlock",
  "params": [
    "0x262e1b2ad728475fd6fe88e62d34c200abe6fd693931ddad144059b1eb884e5b"
  ],
  "id": 1
}

Response Example

{
  "jsonrpc": "2.0",
  "result": {
    "block": {
      "header": {
        "parentHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
        "number": "0x0",
        "stateRoot": "0x2a9c5fae68d226bfef7830398114196416ca1799ebb0099fdfa8b7b7ef19adf4",
        "extrinsicsRoot": "0x03170a2e7597b7b7e3d84c05391d139a62b157e78786d8c082f29dcf4c111314",
        "digest": {
          "logs": []
        }
      },
      "extrinsics": []
    },
    "justifications": null
  },
  "id": 1
}

The example above shows the Bifrost genesis block (#0), which contains no extrinsics.

Code Examples

cURL

# Latest block
curl https://api-bifrost-polkadot.n.dwellir.com/YOUR_API_KEY \
  -H "Content-Type: application/json" \
  -d '{
    "jsonrpc": "2.0",
    "method": "chain_getBlock",
    "params": [],
    "id": 1
  }'

JavaScript

const request = async (hash) => {
  const params = hash ? [hash] : [];
  const response = await fetch('https://api-bifrost-polkadot.n.dwellir.com/YOUR_API_KEY', {
    method: 'POST',
    headers: { 'Content-Type': 'application/json' },
    body: JSON.stringify({
      jsonrpc: '2.0',
      method: 'chain_getBlock',
      params,
      id: 1
    })
  });
  return (await response.json()).result;
};

const block = await request('0xd4b3a0e3b88b7c25215926bbf7c733f5c31e69c0c8c4b4a86d6ec3f3f086e95d');
console.log('Extrinsics count:', block.block.extrinsics.length);

Rust (subxt)

use subxt::{config::substrate::SubstrateConfig, OnlineClient};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let api = OnlineClient::<SubstrateConfig>::from_url(
        "wss://api-bifrost-polkadot.n.dwellir.com/YOUR_API_KEY"
    ).await?;

    let hash = api.rpc().block_hash(None).await?.expect("best hash");
    let block = api.rpc().block(Some(hash)).await?.expect("block");
    println!("Block #{} has {} extrinsics", block.block.header.number, block.block.extrinsics.len());
    Ok(())
}

Usage Notes

• For production monitoring, pair chain_getBlock with chain_getFinalizedHead to avoid processing non-finalized blocks.
• Extrinsics are returned as SCALE-encoded bytes. Decode them with the Bifrost metadata to extract calls such as timestamp.set, parachainsystem.set_validation_data, or SALP pallet operations.