Add comprehensive README with quick start and integration guide link

- Quick installation and setup instructions
- Basic usage example
- Link to full integration guide at dotcms.com/integrations/google-analytics
- Common metrics reference
- Version history and contributing guidelines

Author: fmontes

README.md

@@ -1,2 +1,138 @@
-# google-analytics
-Provides an integration with google analytics
+# Google Analytics Plugin for dotCMS
+
+OSGi plugin that integrates Google Analytics 4 (GA4) Data API with dotCMS, enabling you to fetch analytics data programmatically via Velocity viewtools.
+
+[![Build and Release](https://github.com/dotCMS/google-analytics/actions/workflows/release.yml/badge.svg)](https://github.com/dotCMS/google-analytics/releases)
+
+## What It Does
+
+This plugin provides a `$analytics` viewtool in Velocity templates for querying Google Analytics 4 data directly from your dotCMS pages. Retrieve metrics like sessions, active users, page views, and more—filtered by dimensions like date, page path, device category, etc.
+
+**Note:** This plugin *fetches* analytics data from Google Analytics. It does NOT add tracking code to your site.
+
+## Quick Start
+
+### Prerequisites
+
+- dotCMS 23.01.10 or higher
+- Google Cloud Platform account with billing enabled
+- Google Analytics 4 property with data to query
+- Service account JSON credentials from Google Cloud
+
+### Installation
+
+1. **Download the latest release**
+   - Go to [Releases](https://github.com/dotCMS/google-analytics/releases)
+   - Download `google-analytics-X.X.X.jar`
+
+2. **Upload to dotCMS**
+   - Log into dotCMS as admin
+   - Go to **System → Dynamic Plugins**
+   - Click **Upload Plugin**
+   - Select the JAR file
+
+3. **Configure the App**
+   - Go to **System → Apps → Google Analytics**
+   - **Application Name**: Any name (e.g., "My GA4 Property")
+   - **Json Key File**: Paste your Google Cloud service account JSON credentials
+   - Click **Save**
+
+### Basic Usage
+
+```velocity
+<h2>Last 7 Days Analytics</h2>
+
+## Your GA4 property ID (just the number)
+#set($propertyId = "488595222")
+
+## Create and configure request
+#set($gaRequest = $analytics.createAnalyticsRequest($propertyId))
+$gaRequest.setStartDate("2026-02-09")
+$gaRequest.setEndDate("2026-02-16")
+$gaRequest.setMetrics("sessions,activeUsers")
+$gaRequest.setDimensions("date")
+
+## Execute query
+#set($gaResponse = $analytics.query($gaRequest))
+
+## Display results
+<table>
+  <thead>
+    <tr><th>Date</th><th>Sessions</th><th>Active Users</th></tr>
+  </thead>
+  <tbody>
+    #foreach($row in $gaResponse.getRowsList())
+    <tr>
+      <td>$row.getDimensionValues(0).getValue()</td>
+      <td>$row.getMetricValues(0).getValue()</td>
+      <td>$row.getMetricValues(1).getValue()</td>
+    </tr>
+    #end
+  </tbody>
+</table>
+```
+
+## Documentation
+
+For complete setup instructions including Google Cloud configuration, Google Analytics permissions, advanced usage, and troubleshooting:
+
+**📖 [Full Integration Guide](https://www.dotcms.com/integrations/google-analytics)**
+
+### Key Topics Covered
+
+- **Google Cloud Platform Setup** - Creating service accounts and enabling the Analytics Data API
+- **Google Analytics Configuration** - Granting access and finding your property ID
+- **Advanced Queries** - Filters, dimensions, metrics, and data processing
+- **Troubleshooting** - OSGi issues, metric errors, variable name conflicts
+- **Available Metrics & Dimensions** - GA4 API schema reference
+
+## Available Metrics
+
+Common GA4 metrics you can query:
+- `sessions` - Number of sessions
+- `activeUsers` - Number of distinct users
+- `screenPageViews` - Total page and screen views
+- `bounceRate` - Percentage of single-page sessions
+- `averageSessionDuration` - Average session duration in seconds
+
+See the [GA4 API Schema](https://developers.google.com/analytics/devguides/reporting/data/v1/api-schema) for the full list.
+
+## Version History
+
+### 0.4.1 (Current)
+- ✅ GA4 compatibility - Changed default metric from `ga:visits` to `sessions`
+- ✅ Fixed OSGi dependency resolution for local/Docker deployments
+- ✅ Added proper Import-Package whitelist for dotCMS classes
+- ✅ Bundle all Google Analytics Data API dependencies inside plugin JAR
+- Compatible with dotCMS 23.01.10+
+
+## Building from Source
+
+```bash
+git clone https://github.com/dotCMS/google-analytics.git
+cd google-analytics
+./gradlew jar
+```
+
+The JAR will be in `build/libs/google-analytics-0.4.1.jar`
+
+## Contributing
+
+Contributions are welcome! Please:
+
+1. Fork the repository
+2. Create a feature branch (`git checkout -b feature/amazing-feature`)
+3. Make your changes
+4. Commit with clear messages
+5. Push to your branch
+6. Open a Pull Request
+
+## Support
+
+- **Issues & Bugs:** [GitHub Issues](https://github.com/dotCMS/google-analytics/issues)
+- **Documentation:** [dotCMS Integration Guide](https://www.dotcms.com/integrations/google-analytics)
+- **dotCMS Docs:** [www.dotcms.com/docs](https://www.dotcms.com/docs)
+
+## License
+
+This plugin is provided as-is by dotCMS.