eth_getLogs - Flashblocks

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

This returns query logs from pre-confirmed transactions, updated every ~200ms.

Parameters

Parameter	Type	Required	Description
filterObject	object	Yes	Filter options object

Filter Object

Field	Type	Required	Description
fromBlock	string	No	Start block number (hex) or "latest", "earliest" or "pending"
toBlock	string	No	End block number (hex) or "latest", "earliest"
address	string/array	No	Contract address or array of addresses
topics	array	No	Array of topic filters (up to 4 topics)
blockHash	string	No	Specific block hash (alternative to fromBlock/toBlock)

Request

cURL

curl --location --request POST 'https://go.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "eth_getLogs",
    "params": [{
      "fromBlock": "pending",
      "toBlock": "pending",
      "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
      "topics": ["0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"]
    }],
    "id": 1
  }'

Axios

const axios = require('axios');

// Query ERC-20 Transfer events
const transferTopic = '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef';

const response = await axios.post('https://go.getblock.io/<ACCESS-TOKEN>/', {
    "jsonrpc": "2.0",
    "method": "eth_getLogs",
    "params": [{
      "fromBlock": "pending",
      "toBlock": "pending",
      "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"
    }],
    "id": 1
  }, {
    headers: { 'Content-Type': 'application/json' }
});

const logs = response.data.result;
console.log('Found', logs.length, 'transfer events');
logs.forEach(log => {
    console.log('Block:', parseInt(log.blockNumber, 16));
    console.log('Tx:', log.transactionHash);
});

Request

import requests

# ERC-20 Transfer event signature
transfer_topic = '0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef'

response = requests.post(
    'https://go.getblock.io/<ACCESS-TOKEN>/',
    headers={'Content-Type': 'application/json'},
    json={
    "jsonrpc": "2.0",
    "method": "eth_getLogs",
    "params": [{
      "fromBlock": "pending",
      "toBlock": "pending",
      "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    }],
    "id": "getblock.io"
  }
)

result = response.json()
logs = result['result']
print(f'Found {len(logs)} transfer events')
for log in logs:
    print(f'Block: {int(log["blockNumber"], 16)}')

Response

{
    "jsonrpc": "2.0",
    "result": [
        {
            "address": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
            "topics": [
                "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
                "0x000000000000000000000000b2cc224c1c9fee385f8ad6a55b4d94e92359dc59",
                "0x00000000000000000000000051c72848c68a965f66fa7a88855f9f7784502a7f"
            ],
            "data": "0x00000000000000000000000000000000000000000000000000000000c2c9d499",
            "blockHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
            "blockNumber": "0x2ddffa0",
            "blockTimestamp": "0x6a465c23",
            "transactionHash": "0xfe22be1e04c2b149559b7244f4c5b03693a071cfa5a834590dc16bed318ebeab",
            "transactionIndex": "0x1",
            "logIndex": "0x0",
            "removed": false
        },
        {
            "address": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
            "topics": [
                "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
                "0x0000000000000000000000004e962bb3889bf030368f56810a9c96b83cb3e778",
                "0x00000000000000000000000051c72848c68a965f66fa7a88855f9f7784502a7f"
            ],
            "data": "0x00000000000000000000000000000000000000000000000000000001309ccb9c",
            "blockHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
            "blockNumber": "0x2ddffa0",
            "blockTimestamp": "0x6a465c23",
            "transactionHash": "0x201d890aee2c4b934801032f2b72e888c6a332cda7ccd76cf9e549bd166bf91a",
            "transactionIndex": "0x3",
            "logIndex": "0x3",
            "removed": false
        },
        {
            "address": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
            "topics": [
                "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
                "0x000000000000000000000000d4dc229a997a73e86c13e3ce8019be02cd4827a6",
                "0x0000000000000000000000009e7243b98a8a9713cb9dc37fe9f18879f0e64dcb"
            ],
            "data": "0x0000000000000000000000000000000000000000000000000000000000d7057c",
            "blockHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
            "blockNumber": "0x2ddffa0",
            "blockTimestamp": "0x6a465c23",
            "transactionHash": "0x0f9c2aee37cff0d3cc5564c685923f6d19ec5c7c6a0d7234ee6fe06655950a2b",
            "transactionIndex": "0xb",
            "logIndex": "0x7",
            "removed": false
        },
        {
            "address": "0x833589fcd6edb6e08f4c7c32d4f71b54bda02913",
            "topics": [
                "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef",
                "0x00000000000000000000000040378d78b14f46c35e2f69590b733e5275ac1d3b",
                "0x000000000000000000000000fb08f1c035c05d5c12e12657baee1d1d951c2c6c"
            ],
            "data": "0x0000000000000000000000000000000000000000000000000000000005f5e100",
            "blockHash": "0x0000000000000000000000000000000000000000000000000000000000000000",
            "blockNumber": "0x2ddffa0",
            "blockTimestamp": "0x6a465c23",
            "transactionHash": "0xc93d2aca48444c29d5538c2a79fe8bc13047f4efa656e0cc6877db0de8ea553c",
            "transactionIndex": "0xd",
            "logIndex": "0xb",
            "removed": false
        },
    ],
    "id": "getblock.io"
}

Response Parameters

Parameter	Type	Description
address	string	Contract address that emitted the log
topics	array	Indexed event parameters (up to 4)
data	string	Non-indexed event data (hex)
blockNumber	string	Block number in hex
transactionHash	string	Transaction hash
transactionIndex	string	Transaction index in block (hex)
blockHash	string	Block hash
logIndex	string	Log index in block (hex)
removed	boolean	True if log was removed due to chain reorg

Use Cases

• Token Transfer Tracking: Monitor ERC-20/ERC-721 transfers

• DEX Event Processing: Track swaps, liquidity events

• Contract Event Indexing: Build event-driven databases

• Real-time Notifications: Alert on specific events

• Historical Analysis: Analyze past contract activity

Error Handling

Error Code	Message	Description
-32602	Invalid params	Invalid filter object
-32603	Internal error	Query range too large or node failure
-32005	Query returned more than limit	Too many logs in response

SDK Integration

Ethers.js

const { ethers } = require('ethers');

const provider = new ethers.JsonRpcProvider('https://go.getblock.io/<ACCESS-TOKEN>/');

async function getLogs() {
    // Using filter
    const filter = {
        address: '0x4200000000000000000000000000000000000006', // WETH
        topics: [
            ethers.id('Transfer(address,address,uint256)')
        ],
        fromBlock: 'pending',
        toBlock: 'latest'
    };
    
    const logs = await provider.getLogs(filter);
    
    logs.forEach(log => {
        console.log('Block:', log.blockNumber);
        console.log('Tx:', log.transactionHash);
        console.log('Data:', log.data);
    });
    
    return logs;
}

// Using Contract interface for parsed events
async function getTransferEvents() {
    const abi = ['event Transfer(address indexed from, address indexed to, uint256 value)'];
    const contract = new ethers.Contract(
        '0x4200000000000000000000000000000000000006',
        abi,
        provider
    );
    
    const filter = contract.filters.Transfer();
    const events = await contract.queryFilter(filter, -100, 'latest');
    
    events.forEach(event => {
        console.log('From:', event.args.from);
        console.log('To:', event.args.to);
        console.log('Value:', ethers.formatEther(event.args.value));
    });
    
    return events;
}

getLogs();

Viem

import { createPublicClient, http, parseAbiItem } from 'viem';
import { base } from 'viem/chains';

const client = createPublicClient({
    chain: base,
    transport: http('https://go.getblock.io/<ACCESS-TOKEN>/')
});

async function getLogs() {
    const logs = await client.getLogs({
        address: '0x4200000000000000000000000000000000000006',
        event: parseAbiItem('event Transfer(address indexed from, address indexed to, uint256 value)'),
        fromBlock: 'pending',
        toBlock: 'latest'
    });
    
    logs.forEach(log => {
        console.log('From:', log.args.from);
        console.log('To:', log.args.to);
        console.log('Value:', log.args.value);
    });
    
    return logs;
}

// Watch for new logs
async function watchLogs() {
    const unwatch = client.watchEvent({
        address: '0x4200000000000000000000000000000000000006',
        event: parseAbiItem('event Transfer(address indexed from, address indexed to, uint256 value)'),
        onLogs: logs => {
            logs.forEach(log => {
                console.log('New Transfer:', log.args);
            });
        }
    });
    
    return unwatch;
}

getLogs();