How to create Telegram notifications for Fan Token transfers
Monitoring the Fan Token™ transfers that happen on Chiliz Chain is a great way to stay informed about high-value moves and keep your community in the loop.
With a bit of configuration and code, you can set up a Telegram bot to notify a group whenever a Fan Token™ transfer surpasses a certain threshold.
How to do it using Envio?
Envio is a powerful indexing tool that allows developers to listen for smart contract events on Chiliz and perform an action based on the event.
In this how-to, you’ll see how to configure the bot, capture the relevant events, and automatically trigger Telegram alerts, thus turning your setup into a “whale watcher” for major transfers.
Step 1: Install Prerequisites
Before we begin, ensure you have the required tools installed:
Step 2: Initialize Envio Indexer
Run the following command to initialize an Envio indexer and follow the prompts to generate an ERC20 template on Chiliz Chain (which is an EVM-compatible blockchain):
pnpx envio init
Here are the various selections you should make when prompted:

Step 3: Configure config.yaml
config.yaml
Modify the config.yaml
file to specify the contract address of the FC Barcelona Fan Token™ (or any other Fan Token™ you want to track):
# yaml-language-server: $schema=./node_modules/envio/evm.schema.json
name: fan-token-watcher
description: A simple indexer for Fan Tokens that posts notifications to Telegram on large transfers
networks:
- id: 8888 # Chiliz
start_block: 0
contracts:
- name: ERC20
address: "0xFD3C73b3B09D418841dd6Aff341b2d6e3abA433b" # FC Barcelona
handler: src/EventHandlers.ts
events:
- event: "Transfer(address indexed from, address indexed to, uint256 value)"
field_selection:
transaction_fields:
- "hash"
Note: We remove the approval
event as we are only interested in transfers.
Step 4: Simplify the GraphQL Schema
Modify the schema.graphql
file to track only account balances:
type Account {
id: ID! # Address of the account
balance: BigInt! # Account balance of tokens
}
At this point, we have an ERC20 indexer that listens for events.
Now, let’s add logic to post Telegram notifications.
Step 5: Implement Telegram Notification Logic
Modify the /src/EventHandlers.ts
file to include logic for detecting large transfers and sending Telegram alerts.
import { ERC20 } from "generated";
import { isIndexingAtHead, indexBalances } from "./libs/helpers";
import { fetchEnsHandle } from "./libs/ens";
import { sendMessageToTelegram } from "./libs/telegram";
import { WHALE_THRESHOLD, explorerUrlAddress, explorerUrlTx } from "./constants";
ERC20.Transfer.handler(async ({ event, context }) => {
if (isIndexingAtHead(event.block.timestamp) && event.params.value >= BigInt(WHALE_THRESHOLD)) {
const ensHandleOrFromAddress = await fetchEnsHandle(event.params.from);
const ensHandleOrToAddress = await fetchEnsHandle(event.params.to);
const msg = `FC Barcelona WHALE ALERT 🐋: A new transfer has been made by <a href="${explorerUrlAddress(
event.params.from
)}">${ensHandleOrFromAddress}</a> to <a href="${explorerUrlAddress(
event.params.to
)}">${ensHandleOrToAddress}</a> for ${event.params.value} FC Barcelona! 🔥 - <a href="${explorerUrlTx(
event.transaction.hash
)}">transaction</a>`;
await sendMessageToTelegram(msg);
}
await indexBalances(context, event);
});
The sample /libs/
folder can be found right here on GitHub, including the helpers.ts
and ens.ts
files.
Step 6: Configure Constants
Create a constants.ts
file to store environment variables:
export const EXPLORER_URL_MONAD = process.env.ENVIO_EXPLORER_URL_MONAD;
export const WHALE_THRESHOLD: string = process.env.ENVIO_WHALE_THRESHOLD ?? "1000";
export const BOT_TOKEN = process.env.ENVIO_BOT_TOKEN;
export const CHANNEL_ID = process.env.ENVIO_TELEGRAM_CHANNEL_ID;
export const MESSAGE_THREAD_ID = process.env.ENVIO_TELEGRAM_MESSAGE_THREAD_ID;
export const explorerUrlAddress = (address: string) =>
EXPLORER_URL_MONAD + "address/" + address;
export const explorerUrlTx = (txHash: string) =>
EXPLORER_URL_MONAD + "tx/" + txHash;
Step 7: Sending Telegram Messages
Install the Axios HTTP client:
pnpm i axios
Create a helper function in libs/telegram.ts
to send messages using Axios:
import axios from "axios";
import { CHANNEL_ID, MESSAGE_THREAD_ID, BOT_TOKEN } from "../constants";
export const sendMessageToTelegram = async (message: string): Promise<void> => {
try {
const apiUrl = `https://api.telegram.org/bot${BOT_TOKEN}/sendMessage`;
await axios.post(apiUrl, {
chat_id: CHANNEL_ID,
text: message,
parse_mode: "HTML",
});
} catch (error) {
console.error("Error sending message:", error);
}
};
Step 8: Final Configuration and Running the Indexer
Configure .env
File
.env
Filecp .env.example .env
Edit .env
with your Telegram bot credentials:
ENVIO_BOT_TOKEN=
ENVIO_TELEGRAM_CHANNEL_ID=
ENVIO_TELEGRAM_MESSAGE_THREAD_ID=
ENVIO_EXPLORER_URL="https://chiliscan.com/"
ENVIO_WHALE_THRESHOLD=1000
Create a Telegram Bot
Message
@BotFather
on Telegram and run:/newbot
Follow the prompts to get your bot token.
Add the bot to your Telegram group and run
/start
.Visit
https://api.telegram.org/bot<YourBOTToken>/getUpdates
to find the group chat ID.
If you created the new group with the bot and you only get {"ok":true,"result":[]}
, remove and add the bot again to the group.
Finally, install dependencies and start the indexer
pnpm i
pnpm envio dev
With this setup, you now have an Envio-powered indexer that listens for Fan Token transfers and posts whale alerts to Telegram.

To go further, you can self-host the indexer or deploy it to Envio’s hosted service.
And since we are saving the balances, it can be used as a GraphQL balance API too.
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