chore(Telemetry) #30079 : Move telemetry plugin into core - Part 2 (#…

…30570)

# IMPORTANT NOTE
Changes in the following classes:
* `DotRestApplication.java`
* `SimpleWebInterceptorDelegateImpl`
* `InterceptorFilter`

**Are 100% temporary**. They will just be there until we make sure that
the Telemetry migration is working as expected. Once that is done, we'll
get rid of them.

### Proposed Changes
* Second part of the Telemetry Plug-In migration.
* This PR introduces a new Feature Flag that allows you to enable the
Telemetry feature embedded in the `core` project, or fall back to using
the provided Telemetry Plug-In:
```
DOT_FEATURE_FLAG_TELEMETRY_CORE_ENABLED
```
* Such a flag will be disabled, by default.
* Several classes were refactored in order to comply with the new CDI
approach for inserting instances into classes.
* Additional debugging has been added to Telemetry classes.
* Some Javadoc has been added and formatted, as required.

dotCMS/src/main/java/com/dotcms/filters/interceptor/SimpleWebInterceptorDelegateImpl.java

@@ -1,7 +1,11 @@
 package com.dotcms.filters.interceptor;
 
 import com.dotcms.repackage.com.google.common.annotations.VisibleForTesting;
+import com.dotcms.rest.config.DotRestApplication;
+import com.dotmarketing.util.Config;
+import com.dotmarketing.util.Logger;
 import com.dotmarketing.util.RegEX;
+import io.vavr.Lazy;
 import org.apache.commons.collections.iterators.ReverseListIterator;
 
 import javax.servlet.http.HttpServletRequest;
@@ -30,6 +34,9 @@ public class SimpleWebInterceptorDelegateImpl implements WebInterceptorDelegate
     private final AtomicBoolean reverseOrderForPostInvoke =
             new AtomicBoolean(false);
 
+    private static final Lazy<Boolean> ENABLE_TELEMETRY_FROM_CORE = Lazy.of(() ->
+            Config.getBooleanProperty("FEATURE_FLAG_TELEMETRY_CORE_ENABLED", false));
+
     @Override
     public void addBefore(final String webInterceptorName, final WebInterceptor webInterceptor) {
 
@@ -83,7 +90,11 @@ public void add(final int order, final WebInterceptor webInterceptor) {
 
     @Override
     public void addFirst(final WebInterceptor webInterceptor) {
-
+        if (Boolean.TRUE.equals(ENABLE_TELEMETRY_FROM_CORE.get()) &&
+                webInterceptor.getClass().getName().equalsIgnoreCase("com.dotcms.experience.collectors.api.ApiMetricWebInterceptor")) {
+            Logger.warn(DotRestApplication.class, "Bypassing addition of API Metric Web Interceptor from OSGi");
+            return;
+        }
         this.interceptors.add(0, webInterceptor);
         this.init(webInterceptor);
     } // addFirst.

dotCMS/src/main/java/com/dotcms/rest/config/DotRestApplication.java

@@ -1,20 +1,25 @@
 package com.dotcms.rest.config;
 
 import com.dotcms.cdi.CDIUtils;
+import com.dotcms.telemetry.rest.TelemetryResource;
+import com.dotmarketing.util.Config;
+import com.dotmarketing.util.Logger;
 import com.fasterxml.jackson.jaxrs.json.JacksonJaxbJsonProvider;
-import io.swagger.v3.jaxrs2.integration.resources.AcceptHeaderOpenApiResource;
-import io.swagger.v3.jaxrs2.integration.resources.OpenApiResource;
-import org.glassfish.jersey.ext.cdi1x.internal.CdiComponentProvider;
 import io.swagger.v3.oas.annotations.OpenAPIDefinition;
 import io.swagger.v3.oas.annotations.info.Info;
 import io.swagger.v3.oas.annotations.servers.Server;
 import io.swagger.v3.oas.annotations.tags.Tag;
+import io.vavr.Lazy;
+import org.glassfish.jersey.ext.cdi1x.internal.CdiComponentProvider;
+import org.glassfish.jersey.media.multipart.MultiPartFeature;
+import org.glassfish.jersey.server.ResourceConfig;
+
+import javax.ws.rs.ApplicationPath;
+import java.util.ArrayList;
+import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
-import javax.ws.rs.ApplicationPath;
-import org.glassfish.jersey.media.multipart.MultiPartFeature;
-import org.glassfish.jersey.server.ResourceConfig;
 
 /**
  * This class provides the list of all the REST end-points in dotCMS. Every new
@@ -47,18 +52,24 @@
 )
 public class DotRestApplication extends ResourceConfig {
 
-	public DotRestApplication() {
+	private static final Lazy<Boolean> ENABLE_TELEMETRY_FROM_CORE = Lazy.of(() ->
+			Config.getBooleanProperty("FEATURE_FLAG_TELEMETRY_CORE_ENABLED", false));
 
+	public DotRestApplication() {
+		final List<String> packages = new ArrayList<>(List.of(
+				"com.dotcms.rest",
+				"com.dotcms.contenttype.model.field",
+				"com.dotcms.rendering.js",
+				"com.dotcms.ai.rest",
+				"io.swagger.v3.jaxrs2"));
+		if (Boolean.TRUE.equals(ENABLE_TELEMETRY_FROM_CORE.get())) {
+			packages.add(TelemetryResource.class.getPackageName());
+		}
 		register(MultiPartFeature.class).
 		register(JacksonJaxbJsonProvider.class).
 		registerClasses(customClasses.keySet()).
-		packages(
-		  "com.dotcms.rest",
-		  "com.dotcms.contenttype.model.field",
-		  "com.dotcms.rendering.js",
-		  "com.dotcms.ai.rest",
-		  "io.swagger.v3.jaxrs2"
-		).register(CdiComponentProvider.class);
+		packages(packages.toArray(new String[0])).
+		register(CdiComponentProvider.class);
 	}
 
 	/**
@@ -70,10 +81,15 @@ public DotRestApplication() {
 	 * adds a class and reloads
 	 * @param clazz the class ot add
 	 */
-	public static synchronized void addClass(Class<?> clazz) {
+	public static synchronized void addClass(final Class<?> clazz) {
 		if(clazz==null){
 			return;
 		}
+		if (Boolean.TRUE.equals(ENABLE_TELEMETRY_FROM_CORE.get())
+				&& clazz.getName().equalsIgnoreCase("com.dotcms.experience.TelemetryResource")) {
+			Logger.warn(DotRestApplication.class, "Bypassing activation of Telemetry REST Endpoint from OSGi");
+			return;
+		}
 		if (Boolean.TRUE.equals(customClasses.computeIfAbsent(clazz,c -> true))) {
 			final Optional<ContainerReloader> reloader = CDIUtils.getBean(ContainerReloader.class);
             reloader.ifPresent(ContainerReloader::reload);