Add Google Analytics ViewTool for manual GA4 tracking code injection

dotCMS/src/main/java/com/dotcms/analytics/viewtool/GoogleAnalyticsTool.java

@@ -0,0 +1,178 @@
+package com.dotcms.analytics.viewtool;
+
+import com.dotmarketing.beans.Host;
+import com.dotmarketing.business.web.HostWebAPI;
+import com.dotmarketing.business.web.WebAPILocator;
+import com.dotmarketing.util.Logger;
+import com.dotmarketing.util.UtilMethods;
+import org.apache.velocity.tools.view.context.ViewContext;
+import org.apache.velocity.tools.view.tools.ViewTool;
+
+import javax.servlet.http.HttpServletRequest;
+
+/**
+ * ViewTool for generating Google Analytics 4 (GA4) tracking code in Velocity templates.
+ * 
+ * This tool provides a simple way to include GA4 tracking code in templates by reading
+ * the tracking ID from the current site's googleAnalytics field, or by providing a custom
+ * tracking ID as a parameter.
+ * 
+ * Usage in Velocity templates:
+ * <pre>
+ * ## Include GA4 tracking code from site configuration
+ * $googleAnalytics.trackingCode()
+ * 
+ * ## Include GA4 tracking code with custom tracking ID
+ * $googleAnalytics.trackingCode("G-CUSTOM123")
+ * 
+ * ## With null check
+ * #if($googleAnalytics.trackingId)
+ *   $googleAnalytics.trackingCode()
+ * #end
+ * </pre>
+ * 
+ * Benefits of manual inclusion:
+ * - Developers have full control over placement in the template
+ * - Can be conditionally included based on user consent
+ * - Can override tracking ID with custom value
+ * - No automatic HTML parsing/modification overhead
+ * - More transparent and easier to debug
+ * 
+ * @author dotCMS
+ */
+public class GoogleAnalyticsTool implements ViewTool {
+
+    private static final String GOOGLE_ANALYTICS_PROPERTY = "googleAnalytics";
+
+    private HttpServletRequest request;
+    private HostWebAPI hostWebAPI;
+
+    /**
+     * Default constructor - resolves HostWebAPI lazily via WebAPILocator
+     */
+    public GoogleAnalyticsTool() {
+        this(null);
+    }
+
+    /**
+     * Constructor for testing/dependency injection
+     *
+     * @param hostWebAPI the HostWebAPI to use, or null to resolve lazily
+     */
+    public GoogleAnalyticsTool(final HostWebAPI hostWebAPI) {
+        this.hostWebAPI = hostWebAPI;
+    }
+
+    private HostWebAPI getHostWebAPI() {
+        if (this.hostWebAPI == null) {
+            this.hostWebAPI = WebAPILocator.getHostWebAPI();
+        }
+        return this.hostWebAPI;
+    }
+
+    @Override
+    public void init(final Object initData) {
+        if (initData instanceof ViewContext) {
+            this.request = ((ViewContext) initData).getRequest();
+        }
+    }
+
+    /**
+     * Gets the Google Analytics tracking ID from the current site.
+     * 
+     * @return The GA4 tracking ID (e.g., "G-XXXXXXXXXX") or null if not set
+     */
+    public String getTrackingId() {
+        try {
+            final Host site = getHostWebAPI().getCurrentHostNoThrow(request);
+            if (site != null) {
+                final String trackingId = site.getStringProperty(GOOGLE_ANALYTICS_PROPERTY);
+                if (UtilMethods.isSet(trackingId)) {
+                    return trackingId;
+                }
+            }
+        } catch (Exception e) {
+            Logger.error(this, "Error retrieving Google Analytics tracking ID", e);
+        }
+        return null;
+    }
+
+    /**
+     * Generates the complete Google Analytics 4 tracking code using the site's configured tracking ID.
+     * 
+     * This includes the gtag.js script tag and initialization code.
+     * Place this code in your template where you want the tracking code to appear
+     * (typically before the closing &lt;/body&gt; tag).
+     * 
+     * Usage in Velocity:
+     * <pre>
+     * $googleAnalytics.trackingCode()
+     * </pre>
+     * 
+     * @return The complete GA4 tracking code HTML, or empty string if no tracking ID is set
+     */
+    public String trackingCode() {
+        final String trackingId = getTrackingId();
+
+        if (!UtilMethods.isSet(trackingId)) {
+            Logger.debug(this, "No Google Analytics tracking ID found for current site");
+            return "";
+        }
+
+        return generateGA4Script(trackingId);
+    }
+
+    /**
+     * Generates the complete Google Analytics 4 tracking code using a custom tracking ID.
+     * 
+     * This allows overriding the site's tracking ID with a custom value, useful for
+     * multi-environment setups or testing purposes.
+     * 
+     * Usage in Velocity:
+     * <pre>
+     * $googleAnalytics.trackingCode("G-CUSTOM123")
+     * </pre>
+     * 
+     * @param customTrackingId the custom GA4 tracking ID to use (e.g., "G-XXXXXXXXXX")
+     * @return The complete GA4 tracking code HTML, or empty string if tracking ID is not set
+     */
+    public String trackingCode(final String customTrackingId) {
+        if (!UtilMethods.isSet(customTrackingId)) {
+            Logger.debug(this, "Custom tracking ID is empty, falling back to site configuration");
+            return trackingCode();
+        }
+
+        return generateGA4Script(customTrackingId);
+    }
+
+    /**
+     * Generates the complete Google Analytics 4 tracking code.
+     * 
+     * @deprecated Use {@link #trackingCode()} instead. This method is kept for backward compatibility.
+     * @return The complete GA4 tracking code HTML, or empty string if no tracking ID is set
+     */
+    @Deprecated
+    public String getTrackingCode() {
+        return trackingCode();
+    }
+
+    /**
+     * Generates the GA4 tracking script with the given tracking ID.
+     * 
+     * @param trackingId the GA4 tracking ID
+     * @return the formatted GA4 tracking script
+     */
+    private String generateGA4Script(final String trackingId) {
+        return String.format(
+            "<!-- Google tag (gtag.js) -->\n" +
+            "<script async src=\"https://www.googletagmanager.com/gtag/js?id=%s\"></script>\n" +
+            "<script>\n" +
+            "  window.dataLayer = window.dataLayer || [];\n" +
+            "  function gtag(){dataLayer.push(arguments);}\n" +
+            "  gtag('js', new Date());\n" +
+            "  gtag('config', '%s');\n" +
+            "</script>",
+            trackingId, trackingId
+        );
+    }
+}

dotCMS/src/main/webapp/WEB-INF/toolbox.xml

@@ -327,4 +327,9 @@
 		<scope>request</scope>
 		<class>com.dotcms.analytics.viewtool.AnalyticsTool</class>
 	</tool>
+	<tool>
+		<key>googleAnalytics</key>
+		<scope>request</scope>
+		<class>com.dotcms.analytics.viewtool.GoogleAnalyticsTool</class>
+	</tool>
 </toolbox>