[#1546] Differentiate between PostgreSQL and CockroachDB

Hibernate ORM needs an extra query to differentiate between
PostgreSQL and CockroachDB.

With a custom Dialect and DialectResolver, we can run the
query beforehand and skip that step in Hibernate ORM
(Hibernate ORM expectis a JDBC connection).

Author: DavideD

hibernate-reactive-core/src/main/java/org/hibernate/reactive/dialect/internal/ReactiveCockroachDialect.java

@@ -0,0 +1,19 @@
+/* Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright: Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.reactive.dialect.internal;
+
+import org.hibernate.dialect.CockroachDialect;
+
+/**
+ * The same as {@link CockroachDialect} in Hibernate ORM, but it doesn't require extra
+ * queries to parse the version.
+ */
+public class ReactiveCockroachDialect extends CockroachDialect {
+
+	public ReactiveCockroachDialect(String fullVersion) {
+		super( parseVersion( fullVersion ) );
+	}
+}

hibernate-reactive-core/src/main/java/org/hibernate/reactive/engine/jdbc/dialect/internal/ReactiveStandardDialectResolver.java

@@ -0,0 +1,32 @@
+/* Hibernate, Relational Persistence for Idiomatic Java
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ * Copyright: Red Hat Inc. and Hibernate Authors
+ */
+package org.hibernate.reactive.engine.jdbc.dialect.internal;
+
+import org.hibernate.dialect.Database;
+import org.hibernate.dialect.Dialect;
+import org.hibernate.engine.jdbc.dialect.spi.DialectResolutionInfo;
+import org.hibernate.engine.jdbc.dialect.spi.DialectResolver;
+import org.hibernate.reactive.dialect.internal.ReactiveCockroachDialect;
+
+public class ReactiveStandardDialectResolver implements DialectResolver {
+
+	@Override
+	public Dialect resolveDialect(DialectResolutionInfo info) {
+		// Hibernate ORM runs an extra query to recognize CockroachDB from PostgreSQL
+		// We've already done it, so we are trying to skip that step
+		if ( info.getDatabaseName().startsWith( "Cockroach" ) ) {
+			return new ReactiveCockroachDialect( info.getDatabaseVersion() );
+		}
+
+		for ( Database database : Database.values() ) {
+			if ( database.matchesResolutionInfo( info ) ) {
+				return database.createDialect( info );
+			}
+		}
+
+		return null;
+	}
+}

hibernate-reactive-core/src/main/java/org/hibernate/reactive/provider/impl/ReactiveTypeContributor.java

@@ -18,6 +18,7 @@
 
 import org.hibernate.boot.model.TypeContributions;
 import org.hibernate.boot.model.TypeContributor;
+import org.hibernate.dialect.CockroachDialect;
 import org.hibernate.dialect.DB2Dialect;
 import org.hibernate.dialect.Dialect;
 import org.hibernate.dialect.MySQLDialect;
@@ -272,7 +273,7 @@ private static class ReactiveClobJdbcType implements JdbcType {
 		private final int defaultSqlTypeCode;
 
 		public ReactiveClobJdbcType(Dialect dialect) {
-			defaultSqlTypeCode = dialect instanceof PostgreSQLDialect
+			defaultSqlTypeCode = dialect instanceof PostgreSQLDialect || dialect instanceof CockroachDialect
 					? Types.LONGVARCHAR
 					: Types.CLOB;
 		}

hibernate-reactive-core/src/main/java/org/hibernate/reactive/provider/service/NativeParametersHandling.java

@@ -9,6 +9,7 @@
 import java.util.Map;
 
 import org.hibernate.boot.registry.StandardServiceInitiator;
+import org.hibernate.dialect.CockroachDialect;
 import org.hibernate.dialect.Dialect;
 import org.hibernate.dialect.DialectDelegateWrapper;
 import org.hibernate.dialect.PostgreSQLDialect;
@@ -52,7 +53,7 @@ public ParameterMarkerStrategy initiateService(Map<String, Object> configuration
 	 * @return the selected strategy for the dialect, never null
 	 */
 	private ParameterMarkerStrategy recommendRendered(Dialect realDialect) {
-		if ( realDialect instanceof PostgreSQLDialect ) {
+		if ( realDialect instanceof PostgreSQLDialect || realDialect instanceof CockroachDialect ) {
 			return new PostgreSQLNativeParameterMarkers();
 		}
 		if ( realDialect instanceof SQLServerDialect ) {

hibernate-reactive-core/src/main/java/org/hibernate/reactive/provider/service/NoJdbcEnvironmentInitiator.java

@@ -28,17 +28,18 @@
 import io.vertx.sqlclient.spi.DatabaseMetadata;
 
 import static org.hibernate.reactive.logging.impl.LoggerFactory.make;
+import static org.hibernate.reactive.util.impl.CompletionStages.completedFuture;
 import static org.hibernate.reactive.util.impl.CompletionStages.failedFuture;
 
 /**
  * A Hibernate {@link StandardServiceInitiator service initiator} that
  * provides an implementation of {@link JdbcEnvironment} that infers
  * the Hibernate {@link org.hibernate.dialect.Dialect} from the JDBC URL.
  */
-public class NoJdbcEnvironmentInitiator  implements StandardServiceInitiator<JdbcEnvironment> {
+public class NoJdbcEnvironmentInitiator implements StandardServiceInitiator<JdbcEnvironment> {
 
 	/**
-	 * I'm using the same logger category used in {@link org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl}
+	 * I'm using the same logger category used in {@link org.hibernate.engine.jdbc.dialect.internal.DialectFactoryImpl}.
 	 */
 	private static final Log LOG = make( Log.class, new LogCategory( "SQL dialect" ) );
 
@@ -74,8 +75,7 @@ public DialectBuilder(Map<String, Object> configurationValues, ServiceRegistry r
 		public Dialect build() {
 			DialectFactory dialectFactory = registry.getService( DialectFactory.class );
 			Dialect dialect = dialectFactory.buildDialect( configurationValues, this::dialectResolutionInfo );
-			dialect = checkDialect( dialect );
-			return dialect;
+			return checkDialect( dialect );
 		}
 
 		/**
@@ -102,8 +102,9 @@ private DialectResolutionInfo dialectResolutionInfo() {
 
 		private static CompletionStage<ReactiveDialectResolutionInfo> buildResolutionInfo(ReactiveConnection connection) {
 			try {
-				ReactiveDialectResolutionInfo info = new ReactiveDialectResolutionInfo( connection.getDatabaseMetadata() );
-				return connection.close().thenApply( v -> info );
+				final DatabaseMetadata databaseMetadata = connection.getDatabaseMetadata();
+				return resolutionInfoStage( connection, databaseMetadata )
+						.thenCompose( info -> connection.close().thenApply( v -> info ) );
 			}
 			catch (Throwable t) {
 				try {
@@ -117,6 +118,60 @@ private static CompletionStage<ReactiveDialectResolutionInfo> buildResolutionInf
 				}
 			}
 		}
+
+		private static CompletionStage<ReactiveDialectResolutionInfo> resolutionInfoStage(ReactiveConnection connection, DatabaseMetadata databaseMetadata) {
+			if ( databaseMetadata.productName().equalsIgnoreCase( "PostgreSQL" ) ) {
+				// We need to check if the database is PostgreSQL or CockroachDB
+				// Hibernate ORM does it using a query, so we need to check in advance
+				// See org.hibernate.dialect.Database.POSTGRESQL#createDialect
+				return connection.select( "select version()" )
+						.thenApply( DialectBuilder::readFullVersion )
+						.thenApply( fullversion -> {
+							if ( fullversion.startsWith( "Cockroach" ) ) {
+								return new CockroachDatabaseMetadata( fullversion );
+							}
+							return databaseMetadata;
+						} )
+						.thenApply( ReactiveDialectResolutionInfo::new );
+			}
+
+			return completedFuture( new ReactiveDialectResolutionInfo( databaseMetadata ) );
+		}
+
+		private static String readFullVersion(ReactiveConnection.Result result) {
+			return result.hasNext()
+					? (String) result.next()[0]
+					: "";
+		}
+	}
+
+	private static class CockroachDatabaseMetadata implements DatabaseMetadata {
+
+		private final String fullversion;
+
+		public CockroachDatabaseMetadata(String fullversion) {
+			this.fullversion = fullversion;
+		}
+
+		@Override
+		public String productName() {
+			return "CockroachDb";
+		}
+
+		@Override
+		public String fullVersion() {
+			return fullversion;
+		}
+
+		@Override
+		public int majorVersion() {
+			return 0;
+		}
+
+		@Override
+		public int minorVersion() {
+			return 0;
+		}
 	}
 
 	private static class ReactiveDialectResolutionInfo implements DialectResolutionInfo {

hibernate-reactive-core/src/main/resources/META-INF/services/org.hibernate.engine.jdbc.dialect.spi.DialectResolver

@@ -0,0 +1 @@
+org.hibernate.reactive.engine.jdbc.dialect.internal.ReactiveStandardDialectResolver

hibernate-reactive-core/src/test/java/org/hibernate/reactive/FetchedAssociationTest.java

@@ -8,26 +8,25 @@
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
-import jakarta.persistence.CascadeType;
-import jakarta.persistence.Entity;
-import jakarta.persistence.FetchType;
-import jakarta.persistence.GeneratedValue;
-import jakarta.persistence.Id;
-import jakarta.persistence.JoinColumn;
-import jakarta.persistence.ManyToOne;
-import jakarta.persistence.OneToMany;
-import jakarta.persistence.Table;
 
 import org.hibernate.boot.registry.StandardServiceRegistryBuilder;
 import org.hibernate.cfg.Configuration;
 import org.hibernate.reactive.testing.DatabaseSelectionRule;
 import org.hibernate.reactive.testing.SqlStatementTracker;
 
-import org.junit.After;
 import org.junit.Rule;
 import org.junit.Test;
 
 import io.vertx.ext.unit.TestContext;
+import jakarta.persistence.CascadeType;
+import jakarta.persistence.Entity;
+import jakarta.persistence.FetchType;
+import jakarta.persistence.GeneratedValue;
+import jakarta.persistence.Id;
+import jakarta.persistence.JoinColumn;
+import jakarta.persistence.ManyToOne;
+import jakarta.persistence.OneToMany;
+import jakarta.persistence.Table;
 
 import static org.assertj.core.api.Assertions.assertThat;
 import static org.hibernate.reactive.containers.DatabaseConfiguration.DBType.POSTGRESQL;
@@ -54,13 +53,6 @@ protected Configuration constructConfiguration() {
 		return configuration;
 	}
 
-	@After
-	public void cleanDb(TestContext context) {
-		test( context, getSessionFactory()
-				.withTransaction( s -> s.createQuery( "delete from Child" ).executeUpdate()
-						.thenCompose( v -> s.createQuery( "delete from Parent" ).executeUpdate() ) ) );
-	}
-
 	private static boolean isSelectOrInsertQuery(String s) {
 		return s.toLowerCase().startsWith( "select" )
 				|| s.toLowerCase().startsWith( "insert" );
@@ -100,6 +92,7 @@ public void testWithMutiny(TestContext context) {
 	// We don't expect a select from CHILD
 	private String[] getExpectedNativeQueries() {
 		return new String[] {
+				"select version()",
 				"select nextval('PARENT_SEQ')",
 				"insert into PARENT (name,id) values ($1,$2)",
 				"select p1_0.id,p1_0.name from PARENT p1_0",