xds: treat target server authority opaquely for resolving cluster name (#6767)

Fixes usage of target hostname:port in xDS plugin.

The target hostname:port used to construct gRPC channel should be treated opaquely. XdsNameResolver should not try to split it and should use it opaquely for sending LDS requests. In received RouteConfiguration messages, do not stripe off port (if any) for finding the virtual host with domain name matching the requested LDS resource name.

Author: voidzcy

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

@@ -391,19 +391,17 @@ interface EndpointWatcher {
   abstract void shutdown();
 
   /**
-   * Registers a watcher to receive {@link ConfigUpdate} for service with the given hostname and
-   * port.
+   * Registers a watcher to receive {@link ConfigUpdate} for service with the given target
+   * authority.
    *
    * <p>Unlike watchers for cluster data and endpoint data, at most one ConfigWatcher can be
    * registered. Once it is registered, it cannot be unregistered.
    *
-   * @param hostName the host name part of the "xds:" URI for the server name that the gRPC client
-   *     targets for. Must NOT contain port.
-   * @param port the port part of the "xds:" URI for the server name that the gRPC client targets
-   *     for. -1 if not specified.
+   * @param targetAuthority authority of the "xds:" URI for the server name that the gRPC client
+   *     targets for.
    * @param watcher the {@link ConfigWatcher} to receive {@link ConfigUpdate}.
    */
-  void watchConfigData(String hostName, int port, ConfigWatcher watcher) {
+  void watchConfigData(String targetAuthority, ConfigWatcher watcher) {
   }
 
   /**

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

@@ -157,9 +157,6 @@ final class XdsClientImpl extends XdsClient {
   // never change.
   @Nullable
   private ConfigWatcher configWatcher;
-  // The host name portion of "xds:" URI that the gRPC client targets for.
-  @Nullable
-  private String hostName;
   // The "xds:" URI (including port suffix if present) that the gRPC client targets for.
   @Nullable
   private String ldsResourceName;
@@ -233,15 +230,10 @@ private void cleanUpResources() {
   }
 
   @Override
-  void watchConfigData(String hostName, int port, ConfigWatcher watcher) {
-    checkState(configWatcher == null, "watcher for %s already registered", hostName);
+  void watchConfigData(String targetAuthority, ConfigWatcher watcher) {
+    checkState(configWatcher == null, "watcher for %s already registered", targetAuthority);
+    ldsResourceName = checkNotNull(targetAuthority, "targetAuthority");
     configWatcher = checkNotNull(watcher, "watcher");
-    this.hostName = checkNotNull(hostName, "hostName");
-    if (port == -1) {
-      ldsResourceName = hostName;
-    } else {
-      ldsResourceName = hostName + ":" + port;
-    }
     logger.log(XdsLogLevel.INFO, "Started watching config {0}", ldsResourceName);
     if (rpcRetryTimer != null && rpcRetryTimer.isPending()) {
       // Currently in retry backoff.
@@ -540,11 +532,12 @@ private void handleLdsResponse(DiscoveryResponse ldsResponse) {
       //  data or one supersedes the other. TBD.
       if (requestedHttpConnManager.hasRouteConfig()) {
         RouteConfiguration rc = requestedHttpConnManager.getRouteConfig();
-        clusterName = findClusterNameInRouteConfig(rc, hostName);
+        clusterName = findClusterNameInRouteConfig(rc, ldsResourceName);
         if (clusterName == null) {
           errorMessage =
               "Listener " + ldsResourceName + " : cannot find a valid cluster name in any "
-                  + "virtual hosts inside RouteConfiguration with domains matching: " + hostName;
+                  + "virtual hosts inside RouteConfiguration with domains matching: "
+                  + ldsResourceName;
         }
       } else if (requestedHttpConnManager.hasRds()) {
         Rds rds = requestedHttpConnManager.getRds();
@@ -650,14 +643,14 @@ private void handleRdsResponse(DiscoveryResponse rdsResponse) {
     // Resolved cluster name for the requested resource, if exists.
     String clusterName = null;
     if (requestedRouteConfig != null) {
-      clusterName = findClusterNameInRouteConfig(requestedRouteConfig, hostName);
+      clusterName = findClusterNameInRouteConfig(requestedRouteConfig, ldsResourceName);
       if (clusterName == null) {
         adsStream.sendNackRequest(
             ADS_TYPE_URL_RDS, ImmutableList.of(adsStream.rdsResourceName),
             rdsResponse.getVersionInfo(),
             "RouteConfiguration " + requestedRouteConfig.getName() + ": cannot find a "
                 + "valid cluster name in any virtual hosts with domains matching: "
-                + hostName);
+                + ldsResourceName);
         return;
       }
     }

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

@@ -16,7 +16,6 @@
 
 package io.grpc.xds;
 
-import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 
 import com.google.common.base.Stopwatch;
@@ -31,6 +30,7 @@
 import io.grpc.Status.Code;
 import io.grpc.SynchronizationContext;
 import io.grpc.internal.BackoffPolicy;
+import io.grpc.internal.GrpcUtil;
 import io.grpc.internal.JsonParser;
 import io.grpc.internal.ObjectPool;
 import io.grpc.xds.Bootstrapper.BootstrapInfo;
@@ -42,7 +42,6 @@
 import io.grpc.xds.XdsClient.XdsClientFactory;
 import io.grpc.xds.XdsLogger.XdsLogLevel;
 import java.io.IOException;
-import java.net.URI;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.ScheduledExecutorService;
@@ -60,8 +59,6 @@ final class XdsNameResolver extends NameResolver {
 
   private final XdsLogger logger;
   private final String authority;
-  private final String hostName;
-  private final int port;
   private final XdsChannelFactory channelFactory;
   private final SynchronizationContext syncContext;
   private final ScheduledExecutorService timeService;
@@ -82,12 +79,7 @@ final class XdsNameResolver extends NameResolver {
       Supplier<Stopwatch> stopwatchSupplier,
       XdsChannelFactory channelFactory,
       Bootstrapper bootstrapper) {
-    URI nameUri = URI.create("//" + checkNotNull(name, "name"));
-    checkArgument(nameUri.getHost() != null, "Invalid hostname: %s", name);
-    authority =
-        checkNotNull(nameUri.getAuthority(), "nameUri (%s) doesn't have an authority", nameUri);
-    hostName = nameUri.getHost();
-    port = nameUri.getPort();  // -1 if not specified
+    authority = GrpcUtil.checkAuthority(checkNotNull(name, "name"));
     this.channelFactory = checkNotNull(channelFactory, "channelFactory");
     this.syncContext = checkNotNull(args.getSynchronizationContext(), "syncContext");
     this.timeService = checkNotNull(args.getScheduledExecutorService(), "timeService");
@@ -139,7 +131,7 @@ XdsClient createXdsClient() {
     };
     xdsClientPool = new RefCountedXdsClientObjectPool(xdsClientFactory);
     xdsClient = xdsClientPool.getObject();
-    xdsClient.watchConfigData(hostName, port, new ConfigWatcher() {
+    xdsClient.watchConfigData(authority, new ConfigWatcher() {
       @Override
       public void onConfigChanged(ConfigUpdate update) {
         logger.log(