Create a new block filter

POST

https://eth.nownodes.io/

Authorizations

ApiKeyAuthApiKeyAuth

api-key string

NOWNodes API key passed in the api-key header.

Executes the eth_newBlockFilter JSON-RPC method on Ethereum through NOWNodes.

Body

application/json

Create a new block filter

Request payload for Create a new block filter.

jsonrpcstringrequired

JSON-RPC protocol version.

methodstringrequired

JSON-RPC method name.

paramsArray<any>required

This method does not require any parameters.

idintegerrequired

Client-provided request identifier echoed in the response.

Response

200OK

Filter ID created successfully

401Unauthorized

Unauthorized: API key is present but rejected by the NOWNodes gateway.

405Method Not Allowed

Method Not Allowed. Returned by the NOWNodes gateway for malformed or unsupported gateway-level requests.

422Unprocessable Entity

Missing API key. The NOWNodes gateway returns plain text for this error.

500Internal Server Error

Upstream node or gateway error.

Create a new block filter

curl -X POST 'https://eth.nownodes.io/' \
  -H 'Content-Type: application/json' \
  -d '{
    "jsonrpc": "2.0",
    "method": "eth_newBlockFilter",
    "params": [],
    "id": 1
  }'

import { JsonRpcProvider } from "ethers";

const provider = new JsonRpcProvider("https://eth.nownodes.io/");
const result = await provider.send("eth_newBlockFilter", []);
console.log(result);

require 'eth'
require 'json'
require 'net/http'

uri = URI('https://eth.nownodes.io/')
request = Net::HTTP::Post.new(uri)
request['Content-Type'] = 'application/json'
request.body = '{
  "jsonrpc": "2.0",
  "method": "eth_newBlockFilter",
  "params": [],
  "id": 1
}'

response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) do |http|
  http.request(request)
end

puts JSON.parse(response.body)

from web3 import Web3

w3 = Web3(Web3.HTTPProvider("https://eth.nownodes.io/"))
response = w3.provider.make_request("eth_newBlockFilter", [])
print(response)

import { createPublicClient, http } from "viem";

const client = createPublicClient({
  transport: http("https://eth.nownodes.io/"),
});

const result = await client.request({
  method: "eth_newBlockFilter",
  params: [],
});

console.log(result);

const endpoint = "https://eth.nownodes.io/";
const apiKey = "YOUR_API_KEY";

async function nownodesRequest(payload) {
  const response = await fetch(endpoint, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      "api-key": apiKey,
    },
    body: JSON.stringify(payload),
  });

  return response.json();
}

const result = await nownodesRequest({ jsonrpc: "2.0", method: "eth_newBlockFilter", params: [], id: 1 });
console.log(result);

const response = await fetch('https://eth.nownodes.io/', {
  method: 'POST',
  headers: {
    'Content-Type': 'application/json',
  },
  body: JSON.stringify({
      "jsonrpc": "2.0",
      "method": "eth_newBlockFilter",
      "params": [],
      "id": 1
    }),
});

const data = await response.json();

import requests

payload = {
  "jsonrpc": "2.0",
  "method": "eth_newBlockFilter",
  "params": [],
  "id": 1
}

response = requests.post('https://eth.nownodes.io/', json=payload)
data = response.json()

require 'net/http'
require 'json'

uri = URI('https://eth.nownodes.io/')
request = Net::HTTP::Post.new(uri)
request['Content-Type'] = 'application/json'
request.body = '{
    "jsonrpc": "2.0",
    "method": "eth_newBlockFilter",
    "params": [],
    "id": 1
  }'

response = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |http| http.request(request) }
data = JSON.parse(response.body)

Request Body

{
  "jsonrpc": "2.0",
  "method": "eth_newBlockFilter",
  "params": [],
  "id": 1
}

{
  "jsonrpc": "2.0",
  "id": 1,
  "result": "0x10"
}

{
  "jsonrpc": "2.0",
  "id": 1,
  "error": {
    "code": -32602,
    "message": "too many arguments, want at most 0"
  }
}

Unknown API_key

Method Not Allowed

Missing API_key

{
  "jsonrpc": "2.0",
  "id": 1,
  "error": {
    "code": -32602,
    "message": "too many arguments, want at most 0"
  }
}

Documentation

How to migrate to NOWNodes

Create a new block filter

Authorizations

Body

Response