Thème

Flashblocks#

Flashblocks delivers 200-millisecond preconfirmations on X Layer, drastically reducing wait times for transaction feedback. It is perfect for applications where speed is critical.

Overview#

Flashblocks drastically reduces user-perceived latency and enables near-instantaneous user experiences for applications that require real-time interactions like gaming, high-frequency trading, and social apps.

Leveraging Flashblocks#

Developers can easily leverage the capabilities of Flashblocks in the following ways:

Pending Tag Queries: Query Flashblocks-enabled RPC endpoints using the pending tag.
Raw Data Streaming: Stream Flashblocks data directly from the raw Flashblocks feed.

Supported RPC APIs#

Flashblocks APIs are fully compatible with the Ethereum JSON-RPC standards. Flashblocks APIs use the pending tag for the last received flashblock chain state, which is applied to the pending state.

eth_blockNumber#

Returns the current Flashblocks pending block height.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":["pending"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x832437"
}

eth_call#

Executes a new message call immediately without creating a transaction on the blockchain.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_call","params":[{"to":"0x...","data":"0x..."},"pending"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x0000000000000000000000000000000000000000000000000000000000000001"
}

eth_estimateGas#

Returns an estimate of how much gas is needed for the transaction to complete.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_estimateGas","params":[{"to":"0x...","data":"0x..."},"pending"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x5208"
}

eth_getBalance#

Returns the native token balance for the given address.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getBalance","params":["0x...","pending"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x1234"
}

eth_getTransactionCount#

Returns the transaction count (nonce) for the given address.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getTransactionCount","params":["0x...","pending"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x1b"
}

eth_getCode#

Returns the contract bytecode deployed at the given address.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getCode","params":["0x...","pending"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x606060..."
}

eth_getStorageAt#

Returns the storage value at the given position for the specified address.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getStorageAt","params":["0x...","0x0","pending"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x0000000000000000000000000000000000000000000000000000000000000001"
}

eth_getBlockByHash#

Returns the specified block based on the given block hash. Note that flashblocks and their corresponding canonical blocks share the same block number but may have different block hashes.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getBlockByHash","params":["0x...",true],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "number": "0x832437",
    "hash": "0x...",
    // ... other fields
    "transactions": ["0x..."]
  }
}

eth_getBlockByNumber#

Returns the specified block based on the block number.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getBlockByNumber","params":["pending",true],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "number": "0x832437",
    "hash": "0x...",
    // ... other fields
    "transactions": [{}]
  }
}

eth_getBlockReceipts#

Returns the transaction receipts for the specified block.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getBlockReceipts","params":["pending"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": [
    {
      "transactionHash": "0x...",
      "transactionIndex": "0x0",
      // ... other fields
      "status": "0x1"
    }
  ]
}

eth_getBlockTransactionCountByNumber#

Returns the transaction count for the specified block.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getBlockTransactionCountByNumber","params":["pending"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0xa"
}

eth_getBlockTransactionCountByHash#

Returns the number of transactions in the block with the given block hash.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getBlockTransactionCountByHash","params":["0x..."],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0xa"
}

eth_getTransactionByHash#

Returns the transaction data for the given transaction hash.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getTransactionByHash","params":["0x..."],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "hash": "0x...",
    "nonce": "0x1",
    // ... other fields
    "s": "0x..."
  }
}

eth_getRawTransactionByHash#

Returns the raw transaction data for the given transaction hash.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getRawTransactionByHash","params":["0x..."],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0xf86c018503b9aca008252089400000000000000000000000000000000000000008800de0b6b3a7640000801ba0..."
}

eth_getTransactionReceipt#

Returns the transaction receipt for the given transaction hash.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getTransactionReceipt","params":["0x..."],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "transactionHash": "0x...",
    "transactionIndex": "0x0",
    // ... other fields
    "status": "0x1"
  }
}

eth_getTransactionByBlockNumberAndIndex#

Returns the transaction data for the given block number and transaction index.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getTransactionByBlockNumberAndIndex","params":["pending","0x0"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "hash": "0x...",
    "nonce": "0x1",
    // ... other fields
    "s": "0x..."
  }
}

eth_getTransactionByBlockHashAndIndex#

Returns the transaction data for the given block hash and transaction index.

Shell

curl https://rpc.xlayer.tech/flashblocks -X POST -H "Content-Type: application/json" -d '{"jsonrpc":"2.0","method":"eth_getTransactionByBlockHashAndIndex","params":["0x...","0x0"],"id":1}'

Example Response

Json

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": {
    "hash": "0x...",
    "nonce": "0x1",
    // ... other fields
    "s": "0x..."
  }
}

Quick Start#

The following libraries can work with any RPC endpoints with flashblocks enabled.

Viem#

Javascript

import { createWalletClient, createPublicClient, http, defineChain } from 'viem';
import { privateKeyToAccount } from 'viem/accounts';
import dotenv from 'dotenv';

dotenv.config();

// TODO: create PR to viem
const xlayerPreconf = defineChain({
    id: 195,
    name: 'X Layer Preconf',
    nativeCurrency: { name: 'OKB', symbol: 'OKB', decimals: 18 },
    rpcUrls: {
        default: { http: ['https://rpc.xlayer.tech/flashblocks'] },
    },
    blockExplorers: {
        default: { name: 'Explorer', url: 'https://www.oklink.com/xlayer-test' },
    },
    testnet: true,
});

const account = privateKeyToAccount(process.env.PRIVATE_KEY);

const walletClient = createWalletClient({
    account,
    chain: xlayerPreconf,
    transport: http('https://rpc.xlayer.tech/flashblocks'),
});

const publicClient = createPublicClient({
    chain: xlayerPreconf,
    transport: http('https://rpc.xlayer.tech/flashblocks'),
});

async function sendTransaction() {
    try {
        const submissionTime = new Date();
        const hash = await walletClient.sendTransaction({
            to: '0x0000000000000000000000000000000000000001',
            value: BigInt('100000000000000'),
        });

        console.log(`Transaction submitted time: ${submissionTime.toISOString()}`);
        console.log(`Transaction hash: ${hash}`);

        let receipt = null;
        while (!receipt) {
            try {
                receipt = await publicClient.getTransactionReceipt({ hash });
            } catch (e) {
                await new Promise(resolve => setTimeout(resolve, 10));
            }
        }

        const confirmationTime = new Date();
        console.log(`Transaction confirmed time: ${confirmationTime.toISOString()}`);
        console.log(`Time difference: ${confirmationTime.getTime() - submissionTime.getTime()}ms`);
    } catch (error) {
        console.error('Error sending transaction:', error);
    }
}

sendTransaction();
// node src/ViemExample.js

Ethers#

Javascript

import { ethers } from 'ethers';
import dotenv from 'dotenv';

dotenv.config();

const provider = new ethers.JsonRpcProvider(
    "https://rpc.xlayer.tech/flashblocks"
);

async function sendTransaction() {
    try {
        const tx = {
            to: "0x0000000000000000000000000000000000000001",
            value: ethers.parseEther("0.0000001"),
        };

        // Submit transaction
        const submissionTime = new Date();
        const wallet = new ethers.Wallet(process.env.PRIVATE_KEY, provider);
        const transaction = await wallet.sendTransaction(tx);

        console.log(`Transaction submitted time: ${submissionTime.toISOString()}`);
        console.log(`Transaction hash: ${transaction.hash}`);

        await transaction.wait(0); // Set confirmation count to 0 for flashblocks
        const confirmationTime = new Date();
        console.log(`Transaction confirmed time: ${confirmationTime.toISOString()}`);
        console.log(`Time difference: ${confirmationTime.getTime() - submissionTime.getTime()}ms`);
    } catch (error) {
        console.error('Error sending transaction:', error);
    }
}

sendTransaction();
// node src/EthersExample.js

Websocket endpoints

Node Providers

Table of contents

Overview

Leveraging Flashblocks

Supported RPC APIs

Quick Start