chore: add alerts when the proofs sender has low balance (yetanotherco#643)

Author: JuArce

alerts/.env.example

@@ -1,4 +1,6 @@
 SLACK_WEBHOOK_URL=<YOUR_SLACK_WEBHOOK_URL>
+TELEGRAM_BOT_TOKEN=<YOUR_TELEGRAM_BOT_TOKEN>
+TELEGRAM_CHAT_ID=<YOUR_TELEGRAM_CHAT_ID>
 
 # Variables for contract_alerts.sh
 RPC_URL=<YOUR_RPC_URL>
@@ -9,3 +11,9 @@ VERIFIED_BATCH_TOPIC=<YOUR_VERIFIED_BATCH_TOPIC>
 # Variables for process_errors_alerts.sh
 SERVICE=<YOUR_SERVICE>
 EXPRESSION=<GREP_EXPRESSION>
+
+# Variables for balance_alerts.sh
+RPC_URL=<YOUR_RPC_URL>
+PAYMENT_CONTRACT_ADDRESS=<YOUR_PAYMENT_CONTRACT_ADDRESS>
+BALANCE_THRESHOLD=<YOUR_BALANCE_THRESHOLD_IN_ETH>
+WALLET_ADDRESS=<YOUR_WALLET_ADDRESS>

alerts/balance_alerts.sh

@@ -0,0 +1,51 @@
+#!/bin/bash
+
+# Load env file from $1 path
+source $1
+
+# Function to send slack message
+# @param message
+function send_slack_message() {
+  curl -X POST -H 'Content-type: application/json' \
+    --data "{\"text\":\"$1\"}" \
+    $SLACK_WEBHOOK_URL
+}
+
+# Function to send telegram message
+# @param message
+function send_telegram_message() {
+  curl -s -X POST https://api.telegram.org/bot$TELEGRAM_BOT_TOKEN/sendMessage \
+      -d chat_id=$TELEGRAM_CHAT_ID \
+      -d text="$1" \
+      -d disable_notification=true
+}
+
+# Flags to avoid sending multiple alerts
+balance_alert=false
+
+while :
+do
+  balance_wei=$(cast call --rpc-url $RPC_URL $PAYMENT_CONTRACT_ADDRESS "UserBalances(address)(uint256)" $WALLET_ADDRESS | cut -d' ' -f1)
+
+  balance_eth=$(cast from-wei $balance_wei)
+
+  if [ 1 -eq "$(echo "$balance_eth < $BALANCE_THRESHOLD" | bc)" ]; then
+    message="⚠️ WARNING: Wallet $WALLET_ADDRESS balance ($balance_eth ETH) is below $BALANCE_THRESHOLD ETH"
+    printf "$message\n"
+    if [ "$balance_alert" = false ]; then
+      send_slack_message "$message"
+      send_telegram_message "$message"
+    fi
+    balance_alert=true
+  else
+    message="🟩 INFO: Wallet $WALLET_ADDRESS balance ($balance_eth ETH) is above $BALANCE_THRESHOLD ETH"
+    printf "$message\n"
+    if [ "$balance_alert" = true ]; then
+      send_slack_message "$message"
+      send_telegram_message "$message"
+    fi
+    balance_alert=false
+  fi
+
+  sleep 600
+done