Make default true for the env vars

GRPC_EXPERIMENTAL_XDS_SNI
GRPC_EXPERIMENTAL_XDS_AUTHORITY_REWRITE
GRPC_EXPERIMENTAL_XDS_SYSTEM_ROOT_CERTS

and remove usage of the env var GRPC_EXPERIMENTAL_XDS_GCP_AUTHENTICATION_FILTER and make it enabled.

Author: kannanjgithub

xds/src/main/java/io/grpc/xds/FilterRegistry.java

@@ -17,7 +17,6 @@
 package io.grpc.xds;
 
 import com.google.common.annotations.VisibleForTesting;
-import io.grpc.internal.GrpcUtil;
 import java.util.HashMap;
 import java.util.Map;
 import javax.annotation.Nullable;
@@ -33,18 +32,13 @@ final class FilterRegistry {
 
   private FilterRegistry() {}
 
-  static boolean isEnabledGcpAuthnFilter =
-      GrpcUtil.getFlag("GRPC_EXPERIMENTAL_XDS_GCP_AUTHENTICATION_FILTER", false);
-
   static synchronized FilterRegistry getDefaultRegistry() {
     if (instance == null) {
       instance = newRegistry().register(
               new FaultFilter.Provider(),
               new RouterFilter.Provider(),
-              new RbacFilter.Provider());
-      if (isEnabledGcpAuthnFilter) {
-        instance.register(new GcpAuthenticationFilter.Provider());
-      }
+              new RbacFilter.Provider(),
+              new GcpAuthenticationFilter.Provider());
     }
     return instance;
   }

xds/src/main/java/io/grpc/xds/GcpAuthenticationFilter.java

@@ -17,7 +17,6 @@
 package io.grpc.xds;
 
 import static com.google.common.base.Preconditions.checkNotNull;
-import static io.grpc.xds.FilterRegistry.isEnabledGcpAuthnFilter;
 import static io.grpc.xds.XdsNameResolver.CLUSTER_SELECTION_KEY;
 import static io.grpc.xds.XdsNameResolver.XDS_CONFIG_CALL_OPTION_KEY;
 
@@ -313,10 +312,6 @@ public String getTypeUrl() {
     public AudienceWrapper parse(Any any) throws ResourceInvalidException {
       Audience audience;
       try {
-        if (!isEnabledGcpAuthnFilter) {
-          throw new InvalidProtocolBufferException("Environment variable for GCP Authentication "
-              + "Filter is Not Set");
-        }
         audience = any.unpack(Audience.class);
       } catch (InvalidProtocolBufferException ex) {
         throw new ResourceInvalidException("Invalid Resource in address proto", ex);

xds/src/main/java/io/grpc/xds/XdsClusterResource.java

@@ -66,7 +66,7 @@ class XdsClusterResource extends XdsResourceType<CdsUpdate> {
               System.getProperty("io.grpc.xds.experimentalEnableLeastRequest", "true"));
   @VisibleForTesting
   public static boolean enableSystemRootCerts =
-      GrpcUtil.getFlag("GRPC_EXPERIMENTAL_XDS_SYSTEM_ROOT_CERTS", false);
+      GrpcUtil.getFlag("GRPC_EXPERIMENTAL_XDS_SYSTEM_ROOT_CERTS", true);
   static boolean isEnabledXdsHttpConnect =
       GrpcUtil.getFlag("GRPC_EXPERIMENTAL_XDS_HTTP_CONNECT", false);
 

xds/src/main/java/io/grpc/xds/XdsRouteConfigureResource.java

@@ -69,8 +69,8 @@
 
 class XdsRouteConfigureResource extends XdsResourceType<RdsUpdate> {
 
-  private static final String GRPC_EXPERIMENTAL_XDS_AUTHORITY_REWRITE =
-      "GRPC_EXPERIMENTAL_XDS_AUTHORITY_REWRITE";
+  private static final boolean isXdsAuthorityRewriteEnabled = GrpcUtil.getFlag(
+      "GRPC_EXPERIMENTAL_XDS_AUTHORITY_REWRITE", true);
   @VisibleForTesting
   static boolean enableRouteLookup = GrpcUtil.getFlag("GRPC_EXPERIMENTAL_XDS_RLS_LB", true);
 
@@ -475,8 +475,8 @@ static StructOrError<RouteAction> parseRouteAction(
       case CLUSTER:
         return StructOrError.fromStruct(RouteAction.forCluster(
             proto.getCluster(), hashPolicies, timeoutNano, retryPolicy,
-            GrpcUtil.getFlag(GRPC_EXPERIMENTAL_XDS_AUTHORITY_REWRITE, false)
-            && args.getServerInfo().isTrustedXdsServer() && proto.getAutoHostRewrite().getValue()));
+            isXdsAuthorityRewriteEnabled && args.getServerInfo().isTrustedXdsServer()
+                && proto.getAutoHostRewrite().getValue()));
       case CLUSTER_HEADER:
         return null;
       case WEIGHTED_CLUSTERS:
@@ -510,8 +510,8 @@ static StructOrError<RouteAction> parseRouteAction(
         }
         return StructOrError.fromStruct(VirtualHost.Route.RouteAction.forWeightedClusters(
             weightedClusters, hashPolicies, timeoutNano, retryPolicy,
-            GrpcUtil.getFlag(GRPC_EXPERIMENTAL_XDS_AUTHORITY_REWRITE, false)
-            && args.getServerInfo().isTrustedXdsServer() && proto.getAutoHostRewrite().getValue()));
+            isXdsAuthorityRewriteEnabled && args.getServerInfo().isTrustedXdsServer()
+                && proto.getAutoHostRewrite().getValue()));
       case CLUSTER_SPECIFIER_PLUGIN:
         if (enableRouteLookup) {
           String pluginName = proto.getClusterSpecifierPlugin();
@@ -527,8 +527,7 @@ static StructOrError<RouteAction> parseRouteAction(
           NamedPluginConfig namedPluginConfig = NamedPluginConfig.create(pluginName, pluginConfig);
           return StructOrError.fromStruct(VirtualHost.Route.RouteAction.forClusterSpecifierPlugin(
               namedPluginConfig, hashPolicies, timeoutNano, retryPolicy,
-              GrpcUtil.getFlag(GRPC_EXPERIMENTAL_XDS_AUTHORITY_REWRITE, false)
-              && args.getServerInfo().isTrustedXdsServer()
+              isXdsAuthorityRewriteEnabled && args.getServerInfo().isTrustedXdsServer()
                   && proto.getAutoHostRewrite().getValue()));
         } else {
           return null;

xds/src/main/java/io/grpc/xds/internal/security/trust/CertificateUtils.java

@@ -30,7 +30,7 @@
  * Contains certificate utility method(s).
  */
 public final class CertificateUtils {
-  public static boolean isXdsSniEnabled = GrpcUtil.getFlag("GRPC_EXPERIMENTAL_XDS_SNI", false);
+  public static boolean isXdsSniEnabled = GrpcUtil.getFlag("GRPC_EXPERIMENTAL_XDS_SNI", true);
   public static boolean useChannelAuthorityIfNoSniApplicable
       = GrpcUtil.getFlag("GRPC_USE_CHANNEL_AUTHORITY_IF_NO_SNI_APPLICABLE", false);
 

xds/src/test/java/io/grpc/xds/GrpcXdsClientImplDataTest.java

@@ -2447,7 +2447,6 @@ public Object parse(Any value) {
 
   @Test
   public void processCluster_parsesAudienceMetadata() throws Exception {
-    FilterRegistry.isEnabledGcpAuthnFilter = true;
     MetadataRegistry.getInstance();
 
     Audience audience = Audience.newBuilder()
@@ -2491,14 +2490,11 @@ public void processCluster_parsesAudienceMetadata() throws Exception {
         "FILTER_METADATA", ImmutableMap.of(
             "key1", "value1",
             "key2", 42.0));
-    try {
-      assertThat(update.parsedMetadata().get("FILTER_METADATA"))
-          .isEqualTo(expectedParsedMetadata.get("FILTER_METADATA"));
-      assertThat(update.parsedMetadata().get("AUDIENCE_METADATA"))
-          .isInstanceOf(AudienceWrapper.class);
-    } finally {
-      FilterRegistry.isEnabledGcpAuthnFilter = false;
-    }
+
+    assertThat(update.parsedMetadata().get("FILTER_METADATA"))
+        .isEqualTo(expectedParsedMetadata.get("FILTER_METADATA"));
+    assertThat(update.parsedMetadata().get("AUDIENCE_METADATA"))
+        .isInstanceOf(AudienceWrapper.class);
   }
 
   @Test