Driver config reporting — stage 2: full DRIVER_CONFIG report

core/pom.xml

@@ -160,6 +160,18 @@
       <artifactId>mockito-core</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>com.networknt</groupId>
+      <artifactId>json-schema-validator</artifactId>
+      <scope>test</scope>
+      <exclusions>
+        <!-- A build-time Surefire tree reporter pulled in as a compile dependency; not needed. -->
+        <exclusion>
+          <groupId>me.fabriciorby</groupId>
+          <artifactId>maven-surefire-junit5-tree-reporter</artifactId>
+        </exclusion>
+      </exclusions>
+    </dependency>
     <dependency>
       <groupId>io.reactivex.rxjava2</groupId>
       <artifactId>rxjava</artifactId>

core/src/main/java/com/datastax/oss/driver/api/core/config/DefaultDriverOption.java

@@ -1175,16 +1175,21 @@ public enum DefaultDriverOption implements DriverOption {
    */
   ADDRESS_TRANSLATOR_RESOLVE_ADDRESSES("advanced.address-translator.resolve-addresses"),
   /**
-   * Whether the driver reports its effective configuration to ScyllaDB at connection time.
-   *
-   * <p>When {@code true}, the driver adds two entries to the CQL {@code STARTUP} options, which
-   * ScyllaDB stores in {@code system.clients.client_options} so operators can inspect driver
-   * settings while investigating incidents: a {@code SESSION_ID} on every connection (so the server
-   * can group a session's connections) and a compact JSON payload under the {@code DRIVER_CONFIG}
-   * key on the control connection only. At this stage the {@code DRIVER_CONFIG} payload carries
-   * only schema-version metadata (<code>{"version":1}</code>); reporting of the effective
-   * configuration fields is planned for a later stage. When {@code false}, neither entry is sent
-   * and there is no change on the wire.
+   * Whether the driver reports its effective configuration to the cluster at connection time.
+   * Defaults to {@code true}.
+   *
+   * <p>When {@code true}, the control connection adds a compact JSON payload under the {@code
+   * DRIVER_CONFIG} key to its CQL {@code STARTUP} options, which the server stores in its
+   * client-connection system table ({@code system.clients} on ScyllaDB, {@code
+   * system_views.clients} on Cassandra 4.1+) so operators can inspect driver settings while
+   * investigating incidents. It describes the effective configuration of the driver's default
+   * execution profile (connection/socket settings, timeouts, retry/reconnection/
+   * speculative-execution/load-balancing policies, connection pooling, query defaults, and TLS).
+   * Only the control connection sends it, since it describes the whole session. When {@code false},
+   * {@code DRIVER_CONFIG} is not sent.
+   *
+   * <p>Reporting is best-effort: if the report cannot be built, or would exceed 32 KiB, it is
+   * skipped (with a warning) rather than allowed to interfere with connecting.
    *
    * <p>Value type: boolean
    */

core/src/main/java/com/datastax/oss/driver/api/core/config/OptionsMap.java

@@ -400,7 +400,7 @@ protected static void fillWithDriverDefaults(OptionsMap map) {
     // values) with no sensible scalar default, analogous to how CONFIG_RELOAD_INTERVAL is omitted.
     map.put(TypedDriverOption.CLIENT_ROUTES_NATIVE_TRANSPORT_PORT, 9042);
     map.put(TypedDriverOption.CLIENT_ROUTES_SHARD_AWARENESS_ENABLED, false);
-    map.put(TypedDriverOption.DRIVER_CONFIG_REPORTING_ENABLED, false);
+    map.put(TypedDriverOption.DRIVER_CONFIG_REPORTING_ENABLED, true);
   }
 
   @Immutable

core/src/main/java/com/datastax/oss/driver/api/core/config/TypedDriverOption.java

@@ -976,7 +976,7 @@ public String toString() {
       new TypedDriverOption<>(
           DefaultDriverOption.CLIENT_ROUTES_SHARD_AWARENESS_ENABLED, GenericType.BOOLEAN);
 
-  /** Whether the driver reports its configuration to ScyllaDB at connection time. */
+  /** Whether the driver reports its configuration to the cluster at connection time. */
   public static final TypedDriverOption<Boolean> DRIVER_CONFIG_REPORTING_ENABLED =
       new TypedDriverOption<>(
           DefaultDriverOption.DRIVER_CONFIG_REPORTING_ENABLED, GenericType.BOOLEAN);

core/src/main/java/com/datastax/oss/driver/api/core/ssl/ProgrammaticSslEngineFactory.java

@@ -133,6 +133,11 @@ public SSLEngine newSslEngine(@NonNull EndPoint remoteEndpoint) {
     return engine;
   }
 
+  @Override
+  public boolean isHostnameValidationRequired() {
+    return requireHostnameValidation;
+  }
+
   @Override
   public void close() {
     // nothing to do

core/src/main/java/com/datastax/oss/driver/api/core/ssl/SslEngineFactory.java

@@ -37,4 +37,22 @@ public interface SslEngineFactory extends AutoCloseable {
    */
   @NonNull
   SSLEngine newSslEngine(@NonNull EndPoint remoteEndpoint);
+
+  /**
+   * Whether this factory validates the server certificate against the node's host name.
+   *
+   * <p>This is a diagnostic accessor (reported in the driver-configuration blob sent to the server
+   * at connection time); it does not affect how {@link #newSslEngine} behaves.
+   *
+   * <p>The driver's built-in factories override this to return their real value. It is a {@code
+   * default} method so that existing implementations keep compiling, and the default returns {@code
+   * false} because the driver cannot assume an arbitrary custom factory performs host name
+   * validation, and must not over-report a security control that may not actually be active. Custom
+   * factories that do validate should override this to report accurately.
+   *
+   * @since 4.19.2.1
+   */
+  default boolean isHostnameValidationRequired() {
+    return false;
+  }
 }

core/src/main/java/com/datastax/oss/driver/internal/core/channel/DriverChannel.java

@@ -170,8 +170,7 @@ public int getShardId() {
   }
 
   public ShardingInfo getShardingInfo() {
-    ConnectionShardingInfo info = getSupportedFeatures().getShardingInfo();
-    return info != null ? info.shardingInfo : null;
+    return getSupportedFeatures().getNodeShardingInfo();
   }
 
   public LwtInfo getLwtInfo() {

core/src/main/java/com/datastax/oss/driver/internal/core/channel/ProtocolInitHandler.java

@@ -191,14 +191,25 @@ Message getRequest() {
           return request = Options.INSTANCE;
         case STARTUP:
           Map<String, String> startupOptions = new HashMap<>(context.getStartupOptions());
-          if (featureStore != null) {
-            featureStore.populateStartupOptions(startupOptions);
+          featureStore.populateStartupOptions(startupOptions);
+          // The DRIVER_CONFIG blob describes the whole session, so only the control connection
+          // carries it (options.reportConfig); the other connections are correlated to it by the
+          // SESSION_ID that every connection already carries from context.getStartupOptions().
+          // No-op when driver config reporting is disabled.
+          if (options.reportConfig) {
+            // Sharding info is both of the backend-conditional signals the report needs, in
+            // one value: non-null is the driver's own proxy check for "this is ScyllaDB"
+            // (also used, independently, by
+            // CassandraSchemaQueries.shouldApplyUsingTimeout()), which gates ScyllaDB-only
+            // server-side behavior such as the USING TIMEOUT clause on schema queries; and
+            // its shard count is what ChannelPool keys its pools by, so the reported pool
+            // sizing can be per-shard rather than per-host. It is only populated once the
+            // OPTIONS/SUPPORTED handshake has run, which ChannelFactory always requests.
+            context
+                .getDriverConfigReporter()
+                .populateControlConnectionOptions(
+                    startupOptions, featureStore.getNodeShardingInfo());
           }
-          // Adds SESSION_ID on every connection and DRIVER_CONFIG on the control connection
-          // (options.reportConfig); no-op when driver config reporting is disabled.
-          context
-              .getDriverConfigReporter()
-              .populateStartupOptions(startupOptions, options.reportConfig);
           return request = new Startup(startupOptions);
         case GET_CLUSTER_NAME:
           return request = CLUSTER_NAME_QUERY;