How to Build a Google Ads Zero Spend Alert System (n8n + Replit Tutorial)

Описание: Learn how to build a custom Google Ads monitoring app that alerts you when campaigns stop spending. This complete tutorial shows how my client almost lost an account due to undetected zero spend, and how I built a solution using n8n automation, Replit front-end, and Google Sheets for data management.

⏰ TIMESTAMPS:
00:00 - The Problem: Client Almost Lost an Account
00:51 - App Overview: Custom Account & Campaign Selection
01:53 - Part 1: Form State Workflow (Daily Updates)
02:57 - Parsing Account & Campaign Data
03:29 - Filtering Out Paused Campaigns
04:15 - Part 2: Alert Creation Webhook
05:04 - Form Submission to n8n Integration
05:56 - Duplicate Alert Prevention
06:47 - Confirmation Email Setup
07:02 - Real-Time Dashboard Updates
07:32 - Part 3: Hourly Alert Trigger Logic
08:34 - Alert Frequency Switch Node (Hourly/Daily/Weekly)
09:17 - Pulling Hourly Spend Data from Google Ads API
10:05 - Zero Spend Detection & Parsing
11:08 - Live Troubleshooting: Edge Case Discovery
13:03 - Campaign Status vs Eligibility Issue
14:11 - Alert Routing: Email & Slack Integration
15:22 - Real Alert Examples
16:23 - Replit Front-End Build Process
17:00 - Google Sheets Data Integration
18:00 - Webhook Mapping Issues & Solutions
19:15 - Design Iteration Process
20:40 - Google Sheets Connector Setup
21:15 - Vibe Coding with Replit Agent
22:17 - Final Working Product

🔧 WHAT YOU'LL LEARN:
✅ Build custom Google Ads monitoring dashboards
✅ Set up hourly spend tracking for critical campaigns
✅ Configure selective campaign alerts (not all campaigns)
✅ Integrate n8n workflows with Replit front-ends
✅ Use Google Sheets as a lightweight database
✅ Implement webhook communication between platforms
✅ Route alerts to Slack or Email automatically
✅ Handle edge cases and campaign status logic

💡 THE BUSINESS PROBLEM:

🚨 What Almost Happened:
Friday night: Client discovers campaign with high daily spend
Campaign had $0 spend for 6+ hours
Would have continued through weekend unnoticed
Could have lost the client account

✅ The Solution:
Selective monitoring of critical campaigns only
Hourly automated spend checks
Immediate alerts via Email or Slack
Custom dashboard showing all active alerts
Direct links to problem campaigns in Google Ads

🛠️ TECHNICAL ARCHITECTURE:

📊 Three Main Workflows:

1️⃣ Form State (Daily Updates):
Pulls all accounts from MCC
Fetches all campaigns per account
Filters out paused campaigns
Updates Google Sheets with current state
Populates form dropdowns dynamically

2️⃣ Alert Creation (Webhook):
Receives form submissions from Replit
Parses and formats alert configurations
Prevents duplicate alerts
Saves to Google Sheets alert history
Sends confirmation email

3️⃣ Alert Trigger (Hourly):
Checks all scheduled alerts
Evaluates frequency rules (hourly/daily/weekly)
Pulls last hour spend data via Google Ads API
Detects zero spend on enabled campaigns
Routes notifications to Email or Slack

🎯 KEY FEATURES:

⚙️ Selective Monitoring:
Choose specific accounts to track
Select individual campaigns (not all)
Set alert frequency per campaign
Route to Email, Slack, or both

📱 User Interface:
Configure Alerts tab for setup
Alert History tab shows active monitoring
Last checked timestamp
Last hour spend amount
Direct campaign links for troubleshooting

🔄 Smart Logic:
Duplicate alert prevention
Alert frequency timing (hourly/daily/weekly)
Campaign status filtering (enabled only)
Rate limiting prevention for APIs
Error handling with retry loops

⚠️ EDGE CASES SOLVED:

🐛 Technical Challenges:
Webhook data mapping order issues
Google Sheets rate limiting
Campaign status vs eligibility (scheduled end dates)
Binary data handling in n8n
Replit state management

🔧 Solutions Implemented:
Wait nodes between Google Sheets operations
Merge node duplicate checking
Enhanced campaign status filters
Proper webhook payload formatting
Refresh button for manual data sync

📋 REQUIRED SETUP:

🔑 APIs & Credentials:
Google Ads API developer token
Google Sheets API access
Replit Google Sheets connector
n8n webhook URLs (test + production)
Email or Slack integration

📊 Data Structure:
Sheet 1: Form State (accounts/campaigns)
Sheet 2: Alert History (active alerts)
Automatic column mapping
No manual data entry required

💻 REPLIT BUILD PROCESS:

🎨 Development Approach:
Start with interface design
Copy template from previous project
Use Claude for structural planning
Iterate with Replit Agent 3
Test webhook integration thoroughly
Debug with plan mode reasoning

🔍 Common Issues Fixed:
Webhook payload mapping errors
Google Sheets refresh timing
Form validation errors
Alert history display formatting
Campaign selection order preservation

📧 Want the complete n8n workflows, Replit code, and Google Sheets templates? Email me at [email protected]

#n8n #GoogleAds #Replit