Skip to main content

How to get erc20 token approvals from a block to a block

Prerequisites​

Before getting started, make sure you have the following ready:

  • Node v.14+
  • NPM

Step 1: Setup Blocklens​

First register your Blocklens account and get your Blocklens API Key.

Once you have your Blocklens API Key, install the Blocklens SDK in your project.

npm i blocklens-sdk

Step 2: Get ERC20 token approvals from a block to a block​

In order to get erc20 token approvals from a block to a block, Blocklens provides you a getErc20ApprovalsByBlockRange endpoint to do so.

Here you'll need parameters: from_block, to_block.

Once you've obtained all the from_block, to_block, you can copy the following code:

import Blocklens from "blocklens-sdk";

const blocklens = new Blocklens();
blocklens.init({ apiKey: "YOUR_API_KEY" });

const runApis = async () => {
  const response = await blocklens.ETH_MAINNET.getErc20ApprovalsByBlockRange({"from_block":18246150,"to_block":18246151});
  console.log(response);
};

runApis();

Step 3: Run the script​

ts-node index.ts

In your terminal, you should see the following JSON response with the data: In your terminal, you should see the following JSON response with the data blocks:

{
  "cursor": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpZCI6MTgyNDYxNTEwMDg3MDAwMTMwLCJwYWdlIjoxLCJmcm9tQmxvY2siOjE4MjQ2MTUwLCJ0b0Jsb2NrIjoxODI0NjE1MSwiaWF0IjoxNjk3MDg0MTc4fQ.DcnitLbjJzcMg0Mz48c0iBySxa4PPTdiVk7r04CX3p4",
  "page": 1,
  "limit": 20,
  "total_items": 1,
  "data": [
    {
      "token_name": "Compound",
      "token_symbol": "COMP",
      "token_decimals": 18,
      "contract_address": "0xc00e94Cb662C3520282E6f5717214004A7f26888",
      "transaction_hash": "0xf9d1427d878baf9429a8530d07933a2152f875e4922866abdfab07c63799d6ad",
      "transaction_index": 143,
      "log_index": 307,
      "block_hash": "0x28f7522cc52594826d9853bf25d65ebb382650320ad791cd5434d955a9110d82",
      "block_number": 18246151,
      "from_wallet": "0xfB0018Ad46c669B6a4c0e589C53Db27daF7f7930",
      "to_wallet": "0xc3d688B66703497DAA19211EEdff47f25384cdc3",
      "value": "79228162514264337593543950335",
      "value_decimal": "79228162514.264337593543950335",
      "timestamp": 1696048283
    }
  ]
}

Congratulations 🥳 you just found the get erc20 token approvals from a block to a block on multiple chains with only a few lines of code using the Blocklens Wallet API!

API Reference​

If you want to know more details on the endpoint and optional parameters, check out:

Support​

If you face any trouble following the tutorial, feel free to reach out to our community engineers in our Discord or Forum to get 24/7 developer support.