eth_getFilterChanges - Robinhood

Example code for the eth_getFilterChanges JSON-RPC method. Complete guide to using the eth_getFilterChanges JSON-RPC method in GetBlock.io Web3 documentation.

Returns changes (new entries) since the last call for a given filter. The response shape depends on the filter type — block hashes for block filters, transaction hashes for pending tx filters, log entries for log filters.

Parameters

Parameter	Type	Required	Description
filterId	QUANTITY	Yes	Filter ID

Request Example

cURL

curl --location --request POST 'https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "eth_getFilterChanges",
    "params": [
        "0x1"
    ],
    "id": "getblock.io"
}'

JavaScript (Axios)

import axios from 'axios';

const data = JSON.stringify({
    "jsonrpc": "2.0",
    "method": "eth_getFilterChanges",
    "params": [
        "0x1"
    ],
    "id": "getblock.io"
});

const config = {
    method: 'post',
    url: 'https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/',
    headers: {
        'Content-Type': 'application/json'
    },
    data: data
};

axios(config)
    .then(response => console.log(JSON.stringify(response.data, null, 2)))
    .catch(error => console.log(error));

Python (Requests)

import requests
import json

url = "https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/"

payload = json.dumps({
    "jsonrpc": "2.0",
    "method": "eth_getFilterChanges",
    "params": [
        "0x1"
    ],
    "id": "getblock.io"
})

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

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

Rust (Reqwest)

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": "eth_getFilterChanges",
        "params": [
                "0x1"
        ],
        "id": "getblock.io"
});

    let response = client
        .post("https://shared.us-east-1.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",
    "id": "getblock.io",
    "result": [
        {
            "address": "0x9c8f0e4f8d2e7c6b5a4f3e2d1c0b9a8e7f6d5c4b",
            "blockHash": "0x8b5c6f1a9e8d7c6b5a4f3e2d1c0b9a8e7f6d5c4b3a2b1f9e8d7c6b5a4f3e2d1c",
            "blockNumber": "0x124f80",
            "data": "0x000000000000000000000000000000000000000000000000016345785d8a0000",
            "logIndex": "0x0",
            "removed": false,
            "topics": [
                "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"
            ],
            "transactionHash": "0xa8f9b3c7d2e4f6a1b9c8d7e6f5a4b3c2d1e0f9a8b7c6d5e4f3a2b1c0d9e8f7a6",
            "transactionIndex": "0x0"
        }
    ]
}

Response Parameters

Field	Type	Description
result	array	New entries since last poll — block hashes, transaction hashes, or Log objects depending on filter type

Use Cases

• Periodic polling loop for event-driven applications

• Legacy WebSocket-unfriendly environments

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	Method does not exist or is not enabled on this node
-32603	Internal error	Server-side error while processing the request
429	Too Many Requests	Rate limit exceeded for your plan

SDK Integration

ethers.js

import { ethers } from 'ethers';

const provider = new ethers.JsonRpcProvider('https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/');

// Generic JSON-RPC call (works for any method):
const result = await provider.send('eth_getFilterChanges', ["0x1"]);
console.log(result);

// Many standard methods have typed wrappers on ethers Provider,
// e.g. provider.getBalance(addr), provider.getBlock(n), provider.getTransaction(hash).

viem

import { createPublicClient, http } from 'viem';

const client = createPublicClient({
    transport: http('https://shared.us-east-1.getblock.io/<ACCESS-TOKEN>/')
});

// Generic JSON-RPC request (works for any method):
const result = await client.request({
    method: 'eth_getFilterChanges',
    params: ["0x1"]
});
console.log(result);

// Many standard methods have typed wrappers on PublicClient,
// e.g. client.getBalance({ address }), client.getBlock({ blockNumber }).