Merge pull request #31 from jimmygchen/add-telegram-support

added telegram integration

.env.template

@@ -3,4 +3,7 @@ BEACON_API_LIST=<beacon_node_api_url>
 TWILIO_ACCOUNT_SID=<twilio_account_sid>
 TWILIO_AUTH_TOKEN=<twilio_auth_token>
 SMS_FROM=<sms_sender_number>
-SMS_TO=<sms_recipient_number>
+SMS_TO=<sms_recipient_number>
+TELEGRAM_BOT_API_URL=https://api.telegram.org/bot
+TELEGRAM_BOT_TOKEN=<>
+TELEGRAM_CHAT_ID=<>

README.md

@@ -26,7 +26,7 @@ Please see additional alert types that are being considered in [issue list](http
 
 ## Notification channels
 
-Currently only **SMS** notification is supported - This is the original idea that started this project, to be notified without installing a mobile app and without needing Internet access.
+Currently, **SMS** and **Telegram** notifications are supported - This is the original idea that started this project, to be notified without installing a mobile app and without needing Internet access.
 
 However, additional notification channels are being considered and may be implemented depending on demand. See issue list [here](https://github.com/jchen86/staker-notifier/issues?q=is%3Aissue+is%3Aopen+label%3A%22notification+channel%22)
 
@@ -58,6 +58,8 @@ However, additional notification channels are being considered and may be implem
    | SMS_FROM                               | 'From' number from step 1.                                      |
    | SMS_TO                                 | 'To' number from step 1.                                        |
    | BALANCE_REDUCED_NOTIFY_INTERVAL_EPOCHS | Optional. Number of epochs before resending alert. Default: 20. |
+   | TELEGRAM_BOT_TOKEN                     | You need to create a new bot in Telegram.                       | 
+   | TELEGRAM_CHAT_ID                       | You need to create a new chat and invite the bot to it.         |
 
 
 4. Run one of the following commands:

src/alerts/validator-balance-reduced-alert.js

@@ -47,7 +47,7 @@ const validatorBalanceReducedAlert = (notifier, alertConfig) => {
       }
 
     } else {
-      logger.info(`All ${validators.length} valiators balances are healthy.`)
+      logger.info(`All ${validators.length} validators balances are healthy.`)
     }
   }
 }

src/config.js

@@ -3,20 +3,25 @@ import dotenv from 'dotenv';
 dotenv.config();
 
 const config = {
-  beaconAPIs: process.env.BEACON_API_LIST,
-  sms: {
-    accountSid: process.env.TWILIO_ACCOUNT_SID,
-    authToken: process.env.TWILIO_AUTH_TOKEN,
-    from: process.env.SMS_FROM,
-    to: process.env.SMS_TO
-  },
-  pubkeys: process.env.VALIDATOR_PUBKEYS.split(','),
-  alerts: {
-    validatorBalanceReduced: {
-      minEpochsToTrigger: 3,
-      notifyIntervalEpochs: process.env.BALANCE_REDUCED_NOTIFY_INTERVAL_EPOCHS || 20
+    beaconAPIs: process.env.BEACON_API_LIST,
+    sms: {
+        accountSid: process.env.TWILIO_ACCOUNT_SID,
+        authToken: process.env.TWILIO_AUTH_TOKEN,
+        from: process.env.SMS_FROM,
+        to: process.env.SMS_TO
+    },
+    telegram: {
+        botURL: process.env.TELEGRAM_BOT_API_URL,
+        botToken: process.env.TELEGRAM_BOT_TOKEN,
+        chatID: process.env.TELEGRAM_CHAT_ID
+    },
+    pubkeys: process.env.VALIDATOR_PUBKEYS.split(','),
+    alerts: {
+        validatorBalanceReduced: {
+            minEpochsToTrigger: 3,
+            notifyIntervalEpochs: process.env.BALANCE_REDUCED_NOTIFY_INTERVAL_EPOCHS || 20
+        }
     }
-  }
 }
 
-export { config };
+export {config};

src/main.js

@@ -1,17 +1,25 @@
 import { ValidatorPollingService } from './validator-polling-service.js';
-import { SMSNotifier } from './notifiers/index.js';
+import { SMSNotifier, TelegramNotifier } from './notifiers/index.js';
 import { config } from './config.js';
 import { BeaconAPIClient } from './beacon-api-client.js';
 import { validatorBalanceReducedAlert, validatorStatusChangedAlert } from './alerts/index.js';
 import { logger } from './logger.js';
 
-const smsNotifer = new SMSNotifier(config.sms)
+const notifiers = [];
+if (config.sms.accountSid) notifiers.push(new SMSNotifier(config.sms));
+if (config.telegram.chatID) notifiers.push(new TelegramNotifier(config.telegram));
+
+if (notifiers.length === 0) {
+  throw new Error('Missing notifier config, check your .env file!');
+}
 const beaconApiClient = new BeaconAPIClient(config.beaconAPIs);
 const validatorPollingService = new ValidatorPollingService(beaconApiClient);
 
 validatorPollingService.addValidators(config.pubkeys);
-validatorPollingService.addListener(validatorBalanceReducedAlert(smsNotifer, config.alerts.validatorBalanceReduced));
-validatorPollingService.addListener(validatorStatusChangedAlert(smsNotifer));
+notifiers.forEach((notifier) => {
+  validatorPollingService.addListener(validatorBalanceReducedAlert(notifier, config.alerts.validatorBalanceReduced));
+  validatorPollingService.addListener(validatorStatusChangedAlert(notifier));
+});
 validatorPollingService.start()
   .catch((err) => {
     logger.error(`Error polling validators from Beacon API ${config.beaconAPIs}: `, err);

src/notifiers/index.js

@@ -1 +1,2 @@
 export * from './sms-notifier.js';
+export * from './telegram-notifier.js';

src/notifiers/telegram-notifier.js

@@ -0,0 +1,19 @@
+import {logger} from '../logger.js';
+import {TelegramBotApiClient} from '../telegram-bot-api-client.js';
+
+class TelegramNotifier {
+    constructor(config) {
+        this.chatID = config.chatID;
+        this.client = new TelegramBotApiClient(config.botURL, config.botToken);
+    }
+
+    notify(message) {
+        logger.info(`Sending telegram message to chat_id[${this.chatID}] via bot: ${message}`);
+        this.client.sendMessage(this.chatID, message)
+            .then(r => logger.info("Message sent to " + this.chatID))
+            .catch(err => logger.error('Error sending a message', err));
+    }
+
+}
+
+export {TelegramNotifier};

src/telegram-bot-api-client.js

@@ -0,0 +1,29 @@
+import axios from 'axios';
+import {logger} from './logger.js';
+
+class TelegramBotApiClient {
+    constructor(botAPI, botToken) {
+        this.botAPI = botAPI;
+        this.botToken = botToken;
+        this.http = axios.create({
+            baseURL: this.botAPI + this.botToken
+        })
+    }
+
+    async sendMessage(chatID, message) {
+        const body = {
+            chat_id: chatID,
+            text: message
+        }
+
+        try {
+            await this.http.post('/sendMessage', body);
+        } catch (err) {
+            logger.error(`Request to sendMessage failed with error`, err);
+            throw err
+        }
+    }
+
+}
+
+export {TelegramBotApiClient};