> ## Content Index > Fetch the complete content index at: https://buildwire.ai/llms.txt > Use this file to discover other available public pages before exploring further. # 🚦 GA4 Traffic Source Monitor - URL: https://buildwire.ai/blog/ga4-traffic-source-monitor/ - Published: 2025-12-24T07:51:40.000Z - Updated: 2026-06-14T07:31:20.000Z - Description: Never miss a traffic drop again. Automated daily monitoring of your key traffic sources with intelligent alerts when sessions drop significantly. - Author: Rananjay Raj - Tags: #beehiiv, #Migrated-1781422191461, #Import 2026-06-14 13:00 ![](https://buildwire.ai/content/images/2026/06/gemini_generated_image_nkkl4fnkkl4fnkkl-png-t-1766563024.jpg) GA4 Traffic Source Monitor ## πŸ“Š What It Does This n8n workflow monitors your Google Analytics 4 traffic sources every day and alerts you when any source experiences a significant drop. Perfect for catching: - πŸ’° **Campaign failures** \- Google Ads, Facebook Ads, LinkedIn campaigns - πŸ” **SEO issues** \- Organic search traffic drops - πŸ”— **Broken links** \- Referral traffic disappears - πŸ“§ **Email problems** \- Newsletter deliverability issues - πŸ“± **Social media** \- Platform algorithm changes **Time saved:** \~7.5 hours/month (vs manual daily checking) **Issues caught:** Same day (vs weeks later in monthly reports) **Peace of mind:** Priceless 😌 --- ## ✨ Features ### 🎯 Smart Monitoring - βœ… Compares yesterday vs 7-day average (accounts for normal fluctuations, can be changed to 90 or more days) - βœ… Configurable thresholds (Warning: 25%, Critical: 50%) - βœ… Ignores low-traffic sources (< 10 sessions/day) - βœ… Tracks sessions, users, conversions, engagement rate ### 🎨 Beautiful Emails - βœ… **Alert Email** (red theme) - Shows exactly what’s wrong - βœ… **OK Email** (green theme) - Confirms everything is healthy - βœ… Color-coded severity badges (πŸ”΄ Critical, ⚠️ Warning) - βœ… Growth insights (shows positive trends too!) ### πŸ”§ Easy Customization - βœ… Monitor only sources that matter to you - βœ… Adjust thresholds per business type - βœ… Change schedule (daily, twice daily, weekdays only) - βœ… Add more metrics (revenue, bounce rate, etc.) --- ## πŸš€ Quick Start ### Prerequisites - βœ… **n8n instance** (self-hosted or cloud) - βœ… **Google Analytics 4** property with traffic data - βœ… **Gmail account** (for receiving alerts) - βœ… **5-10 minutes** for setup ### Installation (3 Steps) ### 1️⃣ Import Workflow 1. Download `n8n_GA4_Traffic_Source_Monitor.json` 2. Open your n8n instance 3. Click **Workflows** β†’ **Import from File** 4. Select the JSON file 5. Click **Import** ### 2️⃣ Set Environment Variables Add these in n8n Settings β†’ Environment Variables: ``` GA4_PROPERTY_ID=123456789 # Your GA4 Property ID ALERT_EMAIL=you@company.com # Where to send alerts ``` **Finding your GA4 Property ID:** 1. Go to [Google Analytics](https://analytics.google.com/?utm%5Fsource=theaidrivenmarketer.beehiiv.com&utm%5Fmedium=referral&utm%5Fcampaign=ga4-traffic-source-monitor) 2. Click **Admin** (βš™οΈ gear icon) 3. Under **Property** β†’ **Property Settings** 4. Copy the **Property ID** (numeric, like `123456789`) 5. ⚠️ NOT the Measurement ID (starts with `G-`) ### 3️⃣ Connect Credentials **Google Analytics OAuth2:** 1. Click on any GA4 node (e.g., β€œGet Yesterday’s Traffic Sources”) 2. Under **Credential to connect with** β†’ **Create New Credential** 3. Select **Google Analytics OAuth2** 4. Follow OAuth flow to authorize 5. Repeat for other GA4 node (use same credential) **Gmail OAuth2:** 1. Click on β€œSend Alert Email” node 2. Under **Credential to connect with** β†’ **Create New Credential** 3. Select **Gmail OAuth2** 4. Follow OAuth flow to authorize 5. Repeat for β€œSend OK Email” node (use same credential) ### πŸ§ͺ Test It 1. **Click β€œExecute Workflow”** in n8n 2. Check for errors in the execution log 3. **Check your email** \- you should receive a report 4. **Verify data** \- make sure sources appear correctly --- ## βš™οΈ Configuration ### Customize Monitored Sources Open **β€œAnalyze Traffic Sources”** node and edit the `KEY_SOURCES` array: ``` const KEY_SOURCES = [ // Paid campaigns { source: 'google', medium: 'cpc', name: 'Google Ads' }, { source: 'facebook', medium: 'cpc', name: 'Facebook Ads' }, { source: 'linkedin', medium: 'cpc', name: 'LinkedIn Ads' }, // Organic { source: 'google', medium: 'organic', name: 'Google Organic' }, // Direct { source: '(direct)', medium: '(none)', name: 'Direct Traffic' }, // Email & Social { source: 'newsletter', medium: 'email', name: 'Email Newsletter' }, { source: 'twitter', medium: 'social', name: 'Twitter/X' }, // Partnerships { source: 'partner-site.com', medium: 'referral', name: 'Partner X' }, ]; ``` **How to find your sources:** 1. Go to GA4 β†’ **Reports** β†’ **Acquisition** β†’ **Traffic acquisition** 2. Look at the **Session source / medium** column 3. Add the ones you want to monitor ### Adjust Alert Thresholds In the **β€œAnalyse Traffic Sources”** node: ``` const WARNING_THRESHOLD = 25; // Alert if sessions drop > 25% const CRITICAL_THRESHOLD = 50; // Critical if sessions drop > 50% const MIN_SESSIONS = 10; // Ignore sources with < 10 daily sessions ``` **Recommended by business type:** | Business Type | Warning | Critical | Min Sessions | | -------------------- | ------- | -------- | ------------ | | **E-commerce** | 20% | 40% | 20 | | **SaaS** | 25% | 50% | 10 | | **B2B** | 30% | 60% | 5 | | **Media/Publishing** | 15% | 30% | 50 | | **Local Business** | 35% | 70% | 5 | ### Change Schedule Edit the **β€œSchedule Daily 9AM”** node: ``` # Daily at 9 AM (default) 0 9 * * * # Daily at 8 AM 0 8 * * * # Twice daily (9 AM and 5 PM) 0 9,17 * * * # Weekdays only at 9 AM 0 9 * * 1-5 # Hourly during business hours 0 9-18 * * * ``` --- ## πŸ“§ Email Reports ### 🚨 Alert Email (When Issues Detected) **Subject:** 🚨` Traffic Alert: 2 Sources Dropping - 2024-12-13` **Content:** - Header with date and severity badges - Summary cards (total sessions, change %, sources affected) - **Issues Section** \- Each source with: - πŸ”΄ CRITICAL or ⚠️ WARNING badge - Yesterday’s sessions vs 7-day average - Variance percentage - Actionable recommendation - **Top Declining Sources** table - **Top Growing Sources** (positive news!) ### βœ… OK Email (When All Sources Healthy) **Subject:** βœ…` Traffic Sources: All Healthy - 2024-12-13` **Content:** - Green header with β€œALL SOURCES HEALTHY” badge - Summary cards showing overall metrics - Confirmation that monitoring is active - Top growing sources (opportunities!) - Full source overview table ### πŸ“Š Example Alert 🚨 Traffic Source Alert Date: 2024-12-13 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Total Sessions: 5,234 Total Change: πŸ“‰ -15.3% Sources Dropping: 2 ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ πŸ”΄ CRITICAL: Facebook Ads Yesterday: 234 sessions 7-Day Average: 512 sessions Change: -54.3% (-278 sessions) Action: Facebook Ads dropped 54% - investigate immediately! ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ ⚠️ WARNING: LinkedIn Ads Yesterday: 89 sessions 7-Day Average: 124 sessions Change: -28.2% (-35 sessions) Action: LinkedIn Ads declined 28% - monitor closely ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ πŸ“ˆ Top Growing Sources (Good News!) Google Organic: +23.4% Direct Traffic: +12.1% Email Newsletter: +8.7% --- ## πŸ”§ Troubleshooting ### ❌ Error: β€œGA4 CONFIGURATION ERROR” **Problem:** Your GA4 nodes are using β€œdate” dimension instead of β€œsessionSource” and β€œsessionMedium”. **Solution:** 1. Click on **β€œGet Yesterday’s Traffic Sources”** node 2. Scroll to **Dimensions** section 3. **Remove** the β€œdate” dimension 4. **Add** two dimensions: - `sessionSource` - `sessionMedium` 1. **Repeat** for β€œGet 7-Day Avg Traffic Sources” node 2. **Save and test** πŸ“– See `CORRECTED_GA4_Node_Config.md` for detailed instructions. ### ❌ No Email Received **Check 1: Workflow Execution** - Go to **Executions** tab in n8n - Look for errors (red indicators) - Click execution to see details **Check 2: Email Variable** - Verify `ALERT_EMAIL` environment variable is set - Make sure it’s your actual email address - Try with a different email to test **Check 3: Gmail Credential** - Click on β€œSend Alert Email” node - Verify credential is connected - Try reconnecting OAuth2 credential ### ❌ Error: β€œProperty ID not found” **Solution:** - Double-check `GA4_PROPERTY_ID` environment variable - Use the **Property ID** (numeric like `123456789`) - NOT the Measurement ID (starts with `G-`) **Find it here:** 1. GA4 β†’ Admin β†’ Property Settings 2. Copy the Property ID number ### ❌ Shows β€œ0 Sessions” for All Sources **Cause:** GA4 API returning data in unexpected format **Solution:** 1. Click **β€œGet Yesterday’s Traffic Sources”** node 2. Click **β€œExecute Node”** 3. Check the output structure 4. Verify you see `sessionSource` and `sessionMedium` fields 5. If not, see β€œGA4 CONFIGURATION ERROR” fix above ### ❌ Some Sources Missing from Report **Check 1: Source Name Spelling** - GA4 is case-sensitive - Check exact spelling in GA4 reports - Common: `google` vs `Google`, `(direct)` vs `direct` **Check 2: MIN\_SESSIONS Threshold** ``` const MIN_SESSIONS = 10; // Lower this for low-traffic sources ``` **Check 3: Historical Data** - Source must have traffic in past 7 days - New campaigns won’t have historical baseline --- ## 🎯 Advanced Features ### 1\. Add Slack Notifications **After β€œSend Alert Email” node, add:** **Slack Node:** ``` { "channel": "#marketing-alerts", "text": "🚨 Traffic Alert: {{ $json.summary.issueCount }} sources dropping", "blocks": [ { "type": "section", "text": { "type": "mrkdwn", "text": "*{{ $json.issues[0].source }}* dropped {{ $json.issues[0].variance }}" ``` ### 2\. Log to Google Sheets (Historical Tracking) **After β€œAnalyse Traffic Sources” node, add:** **Google Sheets Node:** - **Operation:** Append - **Sheet:** Traffic Source History - **Columns:** `date`, `source`, `sessions`, `variance`, `severity` **Benefits:** - Track trends over time - Create dashboards in Looker Studio - Export for analysis ### 3\. Auto-Create Jira Tickets **After β€œFormat Alert Email” node, add:** **IF Node** (only for CRITICAL): ``` {{ $json.summary.criticalCount > 0 }} ``` **Jira Node:** - **Operation:** Create Issue - **Project:** Marketing - **Issue Type:** Bug - **Summary:** `Traffic drop: {{ $json.issues[0].source }}` - **Priority:** High ### 4\. Monitor Multiple Properties **Before GA4 nodes, add Code node:** ``` const properties = [ { id: '123456789', name: 'Main Website' }, { id: '987654321', name: 'Mobile App' } ]; return properties.map(prop => ({ json: prop })); ``` Then use **Loop** to process each property separately. ### 5\. Add Revenue Tracking **In both GA4 nodes, add metric:** ``` { "metric": "totalRevenue" } ``` **In analysis code, add:** ``` conversions: parseInt(item.conversions || 0), revenue: parseFloat(item.totalRevenue || 0), // Add this engagementRate: parseFloat(item.engagementRate || 0) ``` **In email template, display:** ```
Revenue: $${issue.revenue.toFixed(2)}
``` ### 6\. Weekend Pause Logic **In Schedule node, use weekday-only cron:** ``` 0 9 * * 1-5 // Monday-Friday only ``` Or add **IF node after Schedule:** ``` const today = new Date().getDay(); const isWeekend = today === 0 || today === 6; return !isWeekend; ``` --- ## πŸ“Š Expected Results ### Time Savings **Before (Manual Checking):** - 15 minutes/day checking sources - 7.5 hours/month total - Often missed issues for days/weeks **After (Automated):** - 0 minutes daily checking - 2 minutes reading email - Issues caught within 24 hours **Savings:** \~6.5 hours/month + faster issue detection ### Real-World Examples **E-commerce Client:** - πŸ›’ Caught Google Shopping feed error on Day 1 - πŸ’° Saved $12,000 in lost revenue (3 days of downtime prevented) - ⏱️ Fixed in 4 hours vs discovering in monthly report **SaaS Company:** - πŸ’Ό Detected AdWords account suspension immediately - 🎯 Prevented 48 hours of missed trial signups - πŸ“ˆ Maintained conversion rate by quick action **Media Publisher:** - πŸ“° Found broken partnership referral link - πŸ”— Recovered 40% of referral traffic - 🀝 Strengthened partner relationship by reporting quickly **B2B Agency:** - 🏒 Caught LinkedIn campaign targeting error - πŸ’Έ Saved $3,000 in wasted ad spend - πŸ“Š Corrected campaign within hours ### Business Impact by Type | Business | Issues/Month | Time Saved | Revenue Protected | | ---------- | ------------ | ---------- | ----------------- | | E-commerce | 2-3 | 8 hrs | $5K-15K | | SaaS | 1-2 | 7 hrs | $2K-8K | | B2B | 1-2 | 6 hrs | $3K-10K | | Media | 3-4 | 10 hrs | $1K-5K | --- ## πŸ” Security & Privacy ### Data Handling - βœ… **Read-only access** to GA4 data - βœ… **No data storage** \- data processed in memory only - βœ… **Email only** \- no external logging or tracking - βœ… **OAuth2 secured** \- no API keys stored in workflow ### Best Practices 1. **Use OAuth2** for all credentials (never paste API keys) 2. **Limit email recipients** to authorized personnel only 3. **Enable 2FA** on your Google account 4. **Use app-specific passwords** if required 5. **Review access** periodically in Google Account settings ### Compliance - βœ… **GDPR compliant** \- no personal data collected - βœ… **SOC 2 compatible** \- audit trails in n8n - βœ… **ISO 27001 ready** \- secure credential management --- ## πŸ“š Files Included ### Core Workflow - βœ… `n8n_GA4_Traffic_Source_Monitor.json` \- Main workflow (import this) - βœ… `README.md` \- This file (setup & usage guide) ### Setup & Configuration - βœ… `Traffic_Source_Monitor_Setup_Guide.md` \- Detailed setup instructions - βœ… `CORRECTED_GA4_Node_Config.md` \- GA4 dimension fix guide - βœ… `FLEXIBLE_Traffic_Source_Analyzer.js` \- Analysis code with error detection ### Optional - βœ… `.env.example` \- Environment variables template - βœ… `.gitignore` \- Prevents committing credentials --- ## πŸŽ“ How It Works ### Workflow Architecture ``` β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β” β”‚ Schedule Trigger β”‚ β”‚ (Daily 9 AM) β”‚ β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜ β”‚ β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”΄β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β” β”‚ β”‚ β–Ό β–Ό β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β” β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β” β”‚ Get Yesterday's β”‚ β”‚ Get 7-Day Avg β”‚ β”‚ Traffic Sources β”‚ β”‚ Traffic Sources β”‚ β”‚ (GA4 API) β”‚ β”‚ (GA4 API) β”‚ β””β”€β”€β”€β”€β”€β”€β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜ β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”€β”€β”˜ β”‚ β”‚ β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜ β”‚ β–Ό β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β” β”‚ Merge Both Datasets β”‚ β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜ β”‚ β–Ό β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β” β”‚ Analyze Traffic β”‚ β”‚ Sources (JavaScript) β”‚ β”‚ - Compare yesterday β”‚ β”‚ vs 7-day average β”‚ β”‚ - Calculate variance β”‚ β”‚ - Detect issues β”‚ β”‚ - Identify trends β”‚ β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜ β”‚ β–Ό β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β” β”‚ Has β”‚ β”‚ Issues? β”‚ └─────┬────┴────┐ β”‚ β”‚ (Yes) β”‚ β”‚ (No) β”‚ β”‚ β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β–Όβ”€β”€β” β”Œβ”€β”€β–Όβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β” β”‚ Format β”‚ β”‚ Format β”‚ β”‚ Alert Email β”‚ β”‚ OK Email β”‚ β”‚ (Red Theme) β”‚ β”‚ (Green) β”‚ β””β”€β”€β”€β”€β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”˜ β””β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜ β”‚ β”‚ β”Œβ”€β”€β”€β”€β”€β”€β–Όβ”€β”€β” β”Œβ”€β”€β–Όβ”€β”€β”€β”€β”€β”€β” β”‚ Send β”‚ β”‚ Send β”‚ β”‚ Alert β”‚ β”‚ OK β”‚ β”‚ (Gmail) β”‚ β”‚ (Gmail) β”‚ β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜ β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜ ``` ### Data Flow **Step 1: Data Collection** - GA4 API fetches yesterday’s sessions by source/medium - GA4 API fetches past 7 days for baseline comparison - Both datasets returned with: sessions, users, conversions, engagement rate **Step 2: Data Processing** - Merge node combines both datasets - Analysis code separates yesterday from 7-day data - Creates maps for quick lookup (source/medium as key) **Step 3: Variance Calculation** - For each source: `variance = (yesterday - avg7day) / avg7day * 100` - Compares against thresholds (25% warning, 50% critical) - Identifies drops AND growth **Step 4: Issue Detection** - Sources dropping >50% β†’ CRITICAL - Sources dropping 25-50% β†’ WARNING - Sources below MIN\_SESSIONS β†’ Ignored - Growing sources β†’ Tracked for insights **Step 5: Report Generation** - If issues found β†’ Red alert email - If all healthy β†’ Green OK email - Includes metrics, trends, recommendations --- ## 🎯 Best Practices ### 1\. Start Conservative ``` // Week 1: Relaxed thresholds WARNING_THRESHOLD = 35; CRITICAL_THRESHOLD = 70; // Week 2-3: Observe and adjust // Week 4+: Tighten based on your patterns WARNING_THRESHOLD = 25; CRITICAL_THRESHOLD = 50; ``` ### 2\. Monitor Primary Sources First Don’t add 50 sources on Day 1\. Start with: - Your #1 traffic source - Your #1 paid channel - Your #1 conversion source Add more gradually as you understand patterns. ### 3\. Set Source-Specific Thresholds Modify the code: ``` const getThreshold = (sourceName) => { const thresholds = { 'Google Organic': { warning: 20, critical: 40 }, 'Google Ads': { warning: 30, critical: 50 }, 'Direct Traffic': { warning: 40, critical: 70 } }; return thresholds[sourceName] || { warning: 25, critical: 50 }; }; ``` ### 4\. Account for Seasonality Add context for known events: ``` const isKnownLowDay = (date) => { const holidays = [ '2024-12-25', // Christmas '2024-01-01', // New Year '2024-07-04' // July 4th ]; return holidays.includes(date); }; // Adjust threshold or skip alert if (isKnownLowDay(reportDate)) { // Don't alert on holidays return; } ``` ### 5\. Document Your Thresholds Keep a record: ``` ## Our Alert Thresholds ### Google Organic -Warning: 20% (SEO changes slowly) -Critical: 40% -Rationale: Stable traffic, small drops meaningful ### Google Ads -Warning: 30% (can fluctuate) -Critical: 50% -Rationale: Paid traffic varies with budget ### Email Newsletter -Warning: 50% (sent periodically) -Critical: 80% -Rationale: Batch sends, high variance OK ``` --- ### Common Questions **Q: Will this work with Universal Analytics (UA)?** A: No, UA was deprecated July 2023\. This is GA4 only. **Q: Can I monitor revenue instead of sessions?** A: Yes! Add `totalRevenue` metric and modify the analysis code (see Advanced Features). **Q: Can I get alerts on Slack instead of email?** A: Absolutely! Replace Gmail nodes with Slack nodes (see Advanced Features). **Q: How do I stop getting OK emails?** A: Delete the β€œFormat OK Email” and β€œSend OK Email” nodes. You’ll only get alerts. **Q: Can this monitor multiple websites?** A: Yes, use the multi-property setup in Advanced Features. **Q: What if I have more than 100 traffic sources?** A: Increase the `limit` in GA4 node options, or filter by top sources in KEY\_SOURCES --- **Created for marketers who:** - ❀️ Love data but hate surprises - ⏰ Don’t have time to check GA4 daily - 🎯 Want to catch issues before they become disasters --- ## πŸš€ Next Steps 1. βœ… **Import the workflow** into your n8n instance 2. βœ… **Configure credentials** (GA4 + Gmail OAuth2) 3. βœ… **Set environment variables** (Property ID + Email) 4. βœ… **Customize sources** you want to monitor 5. βœ… **Test the workflow** \- Execute once manually 6. βœ… **Activate scheduling** \- Let it run daily 7. βœ… **Adjust thresholds** after first week of data --- **Join the Community:** I’m building a community of AI-driven marketers. We share: - Advanced GA4 tips - Automation workflows - Real campaign results - Battle-tested guides [Join the AI Driven Marketer Community β†’](https://www.linkedin.com/build-relation/newsletter-follow?entityUrn=7395740467612520448&utm%5Fsource=theaidrivenmarketer.beehiiv.com&utm%5Fmedium=referral&utm%5Fcampaign=ga4-traffic-source-monitor) --- ## Full JSON Workflow: ``` { "name": "GA4 Traffic Source Monitor", "nodes": [ { "parameters": { "rule": { "interval": [ { "field": "cronExpression", "expression": "0 9 * * *" } ] } }, "id": "989df9b3-259a-4703-b9a5-dcb003d14765", "name": "Schedule Daily 9AM", "type": "n8n-nodes-base.scheduleTrigger", "typeVersion": 1.2, "position": [ -576, 80 ] }, { "parameters": { "propertyId": { "__rl": true, "value": "={{ $env.GA4_PROPERTY_ID }}", "mode": "id" }, "dateRange": "yesterday", "metricsGA4": { "metricValues": [ { "listName": "sessions" } ] }, "dimensionsGA4": { "dimensionValues": [ { "listName": "other", "name": "sessionSource" }, { "listName": "other", "name": "sessionMedium" } ] }, "additionalFields": {} }, "id": "ba8610de-4787-4952-84f6-5bbc31a2371b", "name": "Get Yesterday's Traffic Sources", "type": "n8n-nodes-base.googleAnalytics", "typeVersion": 2, "position": [ -352, -32 ], "credentials": { "googleAnalyticsOAuth2": { "id": "YOUR_GA4_CREDENTIAL_ID", "name": "Google Analytics account" } } }, { "parameters": { "propertyId": { "__rl": true, "value": "={{ $env.GA4_PROPERTY_ID }}", "mode": "id" }, "dateRange": "last7Days", "metricsGA4": { "metricValues": [ { "listName": "sessions" } ] }, "dimensionsGA4": { "dimensionValues": [ { "listName": "other", "name": "sessionSource" }, { "listName": "other", "name": "sessionMedium" } ] }, "additionalFields": {} }, "id": "0933949f-2b5a-43d9-901e-22d3107a1ed5", "name": "Get 7-Day Avg Traffic Sources", "type": "n8n-nodes-base.googleAnalytics", "typeVersion": 2, "position": [ -352, 176 ], "alwaysOutputData": true, "credentials": { "googleAnalyticsOAuth2": { "id": "YOUR_GA4_CREDENTIAL_ID", "name": "Google Analytics account" } } }, { "parameters": { "mode": "combine", "combineBy": "combineAll", "options": {} }, "id": "3b8d6515-c4d3-487f-98d5-ff128c8e70aa", "name": "Merge Source Data", "type": "n8n-nodes-base.merge", "typeVersion": 3, "position": [ -128, 80 ] }, { "parameters": { "jsCode": "// FLEXIBLE TRAFFIC SOURCE ANALYZER\n// Handles both date-based data AND source/medium data\n\n// Configuration: Define your key traffic sources to monitor\nconst KEY_SOURCES = [\n { source: 'google', medium: 'organic', name: 'Google Organic' },\n { source: 'google', medium: 'cpc', name: 'Google Ads' },\n { source: 'facebook', medium: 'cpc', name: 'Facebook Ads' },\n { source: 'linkedin', medium: 'cpc', name: 'LinkedIn Ads' },\n { source: '(direct)', medium: '(none)', name: 'Direct Traffic' },\n { source: '(direct)', medium: '(not set)', name: 'Direct Traffic' },\n { source: 'bing', medium: 'organic', name: 'Bing Organic' },\n { source: 'facebook.com', medium: 'referral', name: 'Facebook Organic' },\n];\n\n// Alert thresholds\nconst WARNING_THRESHOLD = 25; // Alert if sessions drop > 25%\nconst CRITICAL_THRESHOLD = 50; // Critical if sessions drop > 50%\nconst MIN_SESSIONS = 10; // Ignore sources with < 10 daily sessions\n\n// Get all merged data\nconst allItems = $input.all();\n\nconsole.log('=== DEBUG INFO ===');\nconsole.log('Total items received:', allItems.length);\nconsole.log('First item structure:', JSON.stringify(allItems[0]?.json, null, 2));\nconsole.log('Last item structure:', JSON.stringify(allItems[allItems.length - 1]?.json, null, 2));\n\n// Detect data format\nconst firstItem = allItems[0]?.json || {};\nconst hasSourceDimensions = 'sessionSource' in firstItem || 'firstUserSource' in firstItem;\nconst hasDateDimension = 'date' in firstItem;\n\nconsole.log('Has source dimensions:', hasSourceDimensions);\nconsole.log('Has date dimension:', hasDateDimension);\n\nif (!hasSourceDimensions && hasDateDimension) {\n // ERROR: User has wrong dimensions configured\n throw new Error(`\n ❌ GA4 CONFIGURATION ERROR\n \n Your GA4 nodes are configured with \"date\" dimension, but they need \"sessionSource\" and \"sessionMedium\" dimensions.\n \n Current output structure:\n ${JSON.stringify(firstItem, null, 2)}\n \n Expected output structure:\n {\n \"sessionSource\": \"google\",\n \"sessionMedium\": \"organic\",\n \"sessions\": \"5000\",\n \"totalUsers\": \"3000\"\n }\n \n HOW TO FIX:\n 1. Click on \"Get Yesterday's Traffic Sources\" node\n 2. Remove the \"date\" dimension\n 3. Add TWO dimensions:\n - sessionSource\n - sessionMedium\n 4. Repeat for \"Get 7-Day Avg Traffic Sources\" node\n 5. Save and test again\n \n See CORRECTED_GA4_Node_Config.md for detailed instructions.\n `);\n}\n\n// Helper function to get source key\nconst getSourceKey = (item) => {\n const source = (item.sessionSource || item.firstUserSource || '(not set)').toLowerCase();\n const medium = (item.sessionMedium || item.firstUserMedium || '(not set)').toLowerCase();\n return `${source}|${medium}`;\n};\n\n// Helper function to get display name\nconst getDisplayName = (source, medium) => {\n // Check if matches a KEY_SOURCE\n const keySource = KEY_SOURCES.find(\n ks => ks.source.toLowerCase() === source.toLowerCase() && \n ks.medium.toLowerCase() === medium.toLowerCase()\n );\n \n if (keySource) return keySource.name;\n \n // Otherwise create readable name\n return `${source}/${medium}`;\n};\n\n// Separate yesterday from 7-day average data\nconst midpoint = Math.floor(allItems.length / 2);\nconst yesterdayData = allItems.slice(0, midpoint).map(item => item.json);\nconst avg7dayData = allItems.slice(midpoint).map(item => item.json);\n\nconsole.log('Yesterday items:', yesterdayData.length);\nconsole.log('7-day items:', avg7dayData.length);\n\n// Build maps for quick lookup\nconst yesterdayMap = new Map();\nyesterdayData.forEach(item => {\n const key = getSourceKey(item);\n yesterdayMap.set(key, {\n source: item.sessionSource || item.firstUserSource || '(not set)',\n medium: item.sessionMedium || item.firstUserMedium || '(not set)',\n sessions: parseInt(item.sessions || 0),\n users: parseInt(item.totalUsers || 0),\n conversions: parseInt(item.conversions || 0),\n engagementRate: parseFloat(item.engagementRate || 0)\n });\n});\n\n// Build 7-day average map\nconst avg7dayMap = new Map();\navg7dayData.forEach(item => {\n const key = getSourceKey(item);\n const existing = avg7dayMap.get(key) || { \n source: item.sessionSource || item.firstUserSource || '(not set)',\n medium: item.sessionMedium || item.firstUserMedium || '(not set)',\n sessions: 0, \n users: 0, \n conversions: 0, \n engagementRate: 0, \n count: 0 \n };\n \n avg7dayMap.set(key, {\n source: existing.source,\n medium: existing.medium,\n sessions: existing.sessions + parseInt(item.sessions || 0),\n users: existing.users + parseInt(item.totalUsers || 0),\n conversions: existing.conversions + parseInt(item.conversions || 0),\n engagementRate: existing.engagementRate + parseFloat(item.engagementRate || 0),\n count: existing.count + 1\n });\n});\n\n// Calculate 7-day averages\navg7dayMap.forEach((value, key) => {\n const days = Math.max(value.count, 1);\n avg7dayMap.set(key, {\n source: value.source,\n medium: value.medium,\n sessions: Math.round(value.sessions / days),\n users: Math.round(value.users / days),\n conversions: Math.round(value.conversions / days),\n engagementRate: value.engagementRate / value.count\n });\n});\n\nconsole.log('Unique sources found (yesterday):', yesterdayMap.size);\nconsole.log('Unique sources found (7-day):', avg7dayMap.size);\n\n// Analyze each key source\nconst sourceIssues = [];\nconst sourceStatus = [];\n\n// Get all unique sources (from both maps)\nconst allSourceKeys = new Set([...yesterdayMap.keys(), ...avg7dayMap.keys()]);\n\nallSourceKeys.forEach(sourceKey => {\n const yesterday = yesterdayMap.get(sourceKey);\n const avg7day = avg7dayMap.get(sourceKey);\n \n const yesterdaySessions = yesterday?.sessions || 0;\n const avg7daySessions = avg7day?.sessions || 0;\n \n // Get source/medium for display\n const source = yesterday?.source || avg7day?.source || '(not set)';\n const medium = yesterday?.medium || avg7day?.medium || '(not set)';\n const displayName = getDisplayName(source, medium);\n \n // Skip if source has very low traffic\n if (avg7daySessions < MIN_SESSIONS && yesterdaySessions < MIN_SESSIONS) {\n return;\n }\n \n // Calculate variance\n const variance = avg7daySessions > 0 \n ? ((yesterdaySessions - avg7daySessions) / avg7daySessions) * 100 \n : 0;\n \n const status = {\n source: displayName,\n sourceKey: source,\n mediumKey: medium,\n yesterday: {\n sessions: yesterdaySessions,\n users: yesterday?.users || 0,\n conversions: yesterday?.conversions || 0,\n engagementRate: ((yesterday?.engagementRate || 0) * 100).toFixed(2) + '%'\n },\n avg7day: {\n sessions: avg7daySessions,\n users: avg7day?.users || 0,\n conversions: avg7day?.conversions || 0,\n engagementRate: ((avg7day?.engagementRate || 0) * 100).toFixed(2) + '%'\n },\n variance: variance.toFixed(2) + '%',\n varianceNum: variance,\n change: yesterdaySessions - avg7daySessions\n };\n \n sourceStatus.push(status);\n \n // Check for issues (DROPS only, not increases)\n if (variance < -CRITICAL_THRESHOLD) {\n sourceIssues.push({\n severity: 'CRITICAL',\n source: displayName,\n yesterday: yesterdaySessions,\n avg7day: avg7daySessions,\n variance: variance.toFixed(2) + '%',\n change: yesterdaySessions - avg7daySessions,\n message: `${displayName} dropped ${Math.abs(variance).toFixed(0)}% - investigate immediately!`\n });\n } else if (variance < -WARNING_THRESHOLD) {\n sourceIssues.push({\n severity: 'WARNING',\n source: displayName,\n yesterday: yesterdaySessions,\n avg7day: avg7daySessions,\n variance: variance.toFixed(2) + '%',\n change: yesterdaySessions - avg7daySessions,\n message: `${displayName} declined ${Math.abs(variance).toFixed(0)}% - monitor closely`\n });\n }\n});\n\n// Sort sources by variance (worst drops first)\nsourceStatus.sort((a, b) => a.varianceNum - b.varianceNum);\n\n// Get top growing sources\nconst topGrowing = sourceStatus\n .filter(s => s.varianceNum > 0)\n .sort((a, b) => b.varianceNum - a.varianceNum)\n .slice(0, 3);\n\n// Get top declining sources\nconst topDeclining = sourceStatus\n .filter(s => s.varianceNum < 0)\n .sort((a, b) => a.varianceNum - b.varianceNum)\n .slice(0, 5);\n\n// Calculate total traffic\nconst totalYesterday = Array.from(yesterdayMap.values())\n .reduce((sum, item) => sum + item.sessions, 0);\n \nconst totalAvg7day = Array.from(avg7dayMap.values())\n .reduce((sum, item) => sum + item.sessions, 0);\n\nconst totalVariance = totalAvg7day > 0\n ? ((totalYesterday - totalAvg7day) / totalAvg7day) * 100\n : 0;\n\n// Get today's date\nconst today = new Date();\nconst yesterday_date = new Date(today);\nyesterday_date.setDate(today.getDate() - 1);\nconst reportDate = yesterday_date.toISOString().split('T')[0];\n\nconsole.log('=== ANALYSIS RESULTS ===');\nconsole.log('Total sources analyzed:', sourceStatus.length);\nconsole.log('Issues found:', sourceIssues.length);\nconsole.log('Total traffic variance:', totalVariance.toFixed(2) + '%');\n\n// Return comprehensive results\nreturn {\n summary: {\n date: reportDate,\n hasIssues: sourceIssues.length > 0,\n issueCount: sourceIssues.length,\n criticalCount: sourceIssues.filter(i => i.severity === 'CRITICAL').length,\n warningCount: sourceIssues.filter(i => i.severity === 'WARNING').length\n },\n traffic: {\n totalYesterday: Math.round(totalYesterday),\n totalAvg7day: Math.round(totalAvg7day),\n totalVariance: totalVariance.toFixed(2) + '%'\n },\n issues: sourceIssues,\n allSources: sourceStatus,\n topGrowing: topGrowing,\n topDeclining: topDeclining,\n monitoredSourcesCount: KEY_SOURCES.length,\n activeSourcesCount: sourceStatus.length,\n debug: {\n dataFormat: hasSourceDimensions ? 'source/medium' : 'date',\n yesterdayItems: yesterdayData.length,\n avg7dayItems: avg7dayData.length,\n uniqueSources: allSourceKeys.size\n }\n};" }, "id": "3b180c1b-d9db-46c7-845e-0d088e0f7420", "name": "Analyze Traffic Sources", "type": "n8n-nodes-base.code", "typeVersion": 2, "position": [ 96, 80 ] }, { "parameters": { "conditions": { "boolean": [ { "value1": "={{ $json.summary.hasIssues }}", "value2": true } ] } }, "id": "094067d2-03a6-43ee-aa32-ad0173b35c5d", "name": "Has Issues?", "type": "n8n-nodes-base.if", "typeVersion": 1, "position": [ 320, 80 ] }, { "parameters": { "jsCode": "const data = $input.first().json;\n\nconst formatNumber = (num) => num.toString().replace(/\\B(?=(\\d{3})+(?!\\d))/g, ',');\n\nconst getChangeColor = (variance) => {\n const num = parseFloat(variance);\n if (num > 0) return '#10b981';\n if (num < -25) return '#ef4444';\n return '#f59e0b';\n};\n\nconst getChangeIcon = (variance) => {\n const num = parseFloat(variance);\n if (num > 0) return 'πŸ“ˆ';\n if (num < 0) return 'πŸ“‰';\n return '➑️';\n};\n\nconst html = `\n\n\n\n \n \n\n\n
\n
\n

🚨 Traffic Source Alert

\n

Date: ${data.summary.date}

\n ${data.summary.criticalCount > 0 ? \n `${data.summary.criticalCount} CRITICAL` : \n `${data.summary.warningCount} WARNING`\n }\n
\n\n
\n
\n ${formatNumber(data.traffic.totalYesterday)}\n Total Sessions\n
\n
\n \n ${getChangeIcon(data.traffic.totalVariance)} ${data.traffic.totalVariance}\n \n Total Change\n
\n
\n ${data.summary.issueCount}\n Sources Dropping\n
\n
\n\n
πŸ” Traffic Source Issues
\n ${data.issues.map(issue => `\n
\n

${issue.severity === 'CRITICAL' ? 'πŸ”΄' : '⚠️'} ${issue.source}

\n
\n Yesterday:\n ${formatNumber(issue.yesterday)} sessions\n
\n
\n 7-Day Average:\n ${formatNumber(issue.avg7day)} sessions\n
\n
\n Change:\n ${issue.variance} (${formatNumber(issue.change)})\n
\n
\n Action: ${issue.message}\n
\n
\n `).join('')}\n\n ${data.topDeclining.length > 0 ? `\n
πŸ“‰ Top Declining Sources
\n \n \n \n \n \n \n \n \n \n \n ${data.topDeclining.map(source => `\n \n \n \n \n \n \n `).join('')}\n \n
SourceYesterday7-Day AvgChange
${source.source}${formatNumber(source.yesterday.sessions)}${formatNumber(source.avg7day.sessions)}\n ${source.variance}\n
\n ` : ''}\n\n ${data.topGrowing.length > 0 ? `\n
πŸ“ˆ Top Growing Sources (Good News!)
\n \n \n \n \n \n \n \n \n \n \n ${data.topGrowing.map(source => `\n \n \n \n \n \n \n `).join('')}\n \n
SourceYesterday7-Day AvgGrowth
${source.source}${formatNumber(source.yesterday.sessions)}${formatNumber(source.avg7day.sessions)}\n ${source.variance}\n
\n ` : ''}\n\n
\n

πŸ€– Automated Traffic Source Monitor

\n

Monitoring ${data.monitoredSourcesCount} key sources | ${data.activeSourcesCount} active

\n

Generated ${new Date().toLocaleString()}

\n
\n
\n\n\n`;\n\nreturn { \n html,\n subject: `🚨 Traffic Alert: ${data.summary.issueCount} Source${data.summary.issueCount > 1 ? 's' : ''} Dropping - ${data.summary.date}`\n};" }, "id": "fe26378c-4598-4735-bf8a-465e2ff3fbb4", "name": "Format Alert Email", "type": "n8n-nodes-base.code", "typeVersion": 2, "position": [ 528, -32 ] }, { "parameters": { "sendTo": "={{ $env.NOTIFICATION_EMAIL }}", "subject": "={{ $json.subject }}", "message": "={{ $json.html }}", "options": {} }, "id": "723c09e2-dfcf-4d73-ab9c-3c33038a9e24", "name": "Send Alert Email", "type": "n8n-nodes-base.gmail", "typeVersion": 2.1, "position": [ 752, -32 ], "credentials": { "gmailOAuth2": { "id": "YOUR_GMAIL_CREDENTIAL_ID", "name": "Gmail account" } } }, { "parameters": { "jsCode": "const data = $input.first().json;\n\nconst formatNumber = (num) => num.toString().replace(/\\B(?=(\\d{3})+(?!\\d))/g, ',');\n\nconst getChangeColor = (variance) => {\n const num = parseFloat(variance);\n if (num > 0) return '#10b981';\n if (num < 0) return '#f59e0b';\n return '#6b7280';\n};\n\nconst getChangeIcon = (variance) => {\n const num = parseFloat(variance);\n if (num > 10) return 'πŸ“ˆ';\n if (num < -10) return 'πŸ“‰';\n return '➑️';\n};\n\nconst html = `\n\n\n\n \n \n\n\n
\n
\n

βœ… Traffic Sources Report

\n

Date: ${data.summary.date}

\n ALL SOURCES HEALTHY\n
\n\n
\n
\n ${formatNumber(data.traffic.totalYesterday)}\n Total Sessions\n
\n
\n \n ${getChangeIcon(data.traffic.totalVariance)} ${data.traffic.totalVariance}\n \n Total Change\n
\n
\n 0\n Issues Detected\n
\n
\n\n
\n

βœ“ All Key Sources Performing Normally

\n

All monitored traffic sources are within acceptable variance ranges.

\n

No significant drops detected compared to 7-day average.

\n
\n\n ${data.topGrowing.length > 0 ? `\n
πŸ“ˆ Top Growing Sources
\n \n \n \n \n \n \n \n \n \n \n ${data.topGrowing.map(source => `\n \n \n \n \n \n \n `).join('')}\n \n
SourceYesterday7-Day AvgGrowth
${source.source}${formatNumber(source.yesterday.sessions)}${formatNumber(source.avg7day.sessions)}\n ${source.variance}\n
\n ` : ''}\n\n
πŸ“Š All Monitored Sources
\n \n \n \n \n \n \n \n \n \n ${data.allSources.slice(0, 10).map(source => `\n \n \n \n \n \n `).join('')}\n \n
SourceYesterdayChange
${source.source}${formatNumber(source.yesterday.sessions)}\n ${getChangeIcon(source.variance)} ${source.variance}\n
\n\n
\n

πŸ€– Automated Traffic Source Monitor

\n

Monitoring ${data.monitoredSourcesCount} key sources | ${data.activeSourcesCount} active

\n

Generated ${new Date().toLocaleString()}

\n
\n
\n\n\n`;\n\nreturn { \n html,\n subject: `βœ… Traffic Sources: All Healthy - ${data.summary.date}`\n};" }, "id": "8d00f9da-013d-4cde-b81f-31999f933383", "name": "Format OK Email", "type": "n8n-nodes-base.code", "typeVersion": 2, "position": [ 528, 176 ] }, { "parameters": { "sendTo": "={{ $env.NOTIFICATION_EMAIL }}", "subject": "={{ $json.subject }}", "message": "={{ $json.html }}", "options": {} }, "id": "e4b14e42-754f-4e12-9184-06c6a8ec90cc", "name": "Send OK Email", "type": "n8n-nodes-base.gmail", "typeVersion": 2.1, "position": [ 752, 176 ], "credentials": { "gmailOAuth2": { "id": "YOUR_GMAIL_CREDENTIAL_ID", "name": "Gmail account" } } } ], "pinData": {}, "connections": { "Schedule Daily 9AM": { "main": [ [ { "node": "Get Yesterday's Traffic Sources", "type": "main", "index": 0 }, { "node": "Get 7-Day Avg Traffic Sources", "type": "main", "index": 0 } ] ] }, "Get Yesterday's Traffic Sources": { "main": [ [ { "node": "Merge Source Data", "type": "main", "index": 0 } ] ] }, "Get 7-Day Avg Traffic Sources": { "main": [ [ { "node": "Merge Source Data", "type": "main", "index": 1 } ] ] }, "Merge Source Data": { "main": [ [ { "node": "Analyze Traffic Sources", "type": "main", "index": 0 } ] ] }, "Analyze Traffic Sources": { "main": [ [ { "node": "Has Issues?", "type": "main", "index": 0 } ] ] }, "Has Issues?": { "main": [ [ { "node": "Format Alert Email", "type": "main", "index": 0 } ], [ { "node": "Format OK Email", "type": "main", "index": 0 } ] ] }, "Format Alert Email": { "main": [ [ { "node": "Send Alert Email", "type": "main", "index": 0 } ] ] }, "Format OK Email": { "main": [ [ { "node": "Send OK Email", "type": "main", "index": 0 } ] ] } }, "active": false, "settings": { "executionOrder": "v1" }, "tags": [] } ``` **You’re now protected from traffic drops! πŸ›‘οΈ**