GH-2594 - Add withNeo4jConversions to both Neo4jClient and

`ReactiveNeo4jClient`.

Closes #2594.

Author: michael-simons

src/main/java/org/springframework/data/neo4j/core/DefaultNeo4jClient.java

@@ -80,7 +80,7 @@ final class DefaultNeo4jClient implements Neo4jClient {
 		this.userSelectionProvider = builder.userSelectionProvider;
 
 		this.conversionService = new DefaultConversionService();
-		new Neo4jConversions().registerConvertersIn((ConverterRegistry) conversionService);
+		Optional.ofNullable(builder.neo4jConversions).orElseGet(Neo4jConversions::new).registerConvertersIn((ConverterRegistry) conversionService);
 	}
 
 	@Override

src/main/java/org/springframework/data/neo4j/core/DefaultReactiveNeo4jClient.java

@@ -45,6 +45,7 @@
 import java.util.Collections;
 import java.util.HashSet;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.locks.ReentrantReadWriteLock;
 import java.util.function.BiConsumer;
@@ -81,7 +82,7 @@ final class DefaultReactiveNeo4jClient implements ReactiveNeo4jClient {
 		this.userSelectionProvider = builder.impersonatedUserProvider;
 
 		this.conversionService = new DefaultConversionService();
-		new Neo4jConversions().registerConvertersIn((ConverterRegistry) conversionService);
+		Optional.ofNullable(builder.neo4jConversions).orElseGet(Neo4jConversions::new).registerConvertersIn((ConverterRegistry) conversionService);
 	}
 
 	@Override

src/main/java/org/springframework/data/neo4j/core/Neo4jClient.java

@@ -30,6 +30,7 @@
 import org.neo4j.driver.summary.ResultSummary;
 import org.neo4j.driver.types.TypeSystem;
 import org.springframework.core.log.LogAccessor;
+import org.springframework.data.neo4j.core.convert.Neo4jConversions;
 import org.springframework.lang.Nullable;
 
 /**
@@ -75,6 +76,9 @@ class Builder {
 		@Nullable
 		UserSelectionProvider userSelectionProvider;
 
+		@Nullable
+		Neo4jConversions neo4jConversions;
+
 		private Builder(Driver driver) {
 			this.driver = driver;
 		}
@@ -105,6 +109,18 @@ public Builder withUserSelectionProvider(@Nullable UserSelectionProvider userSel
 			return this;
 		}
 
+		/**
+		 * Configures the set of {@link Neo4jConversions} to use.
+		 *
+		 * @param neo4jConversions the set of conversions to use, can be {@literal null}, in this case the default set is used.
+		 * @return The builder
+		 * @since 6.3.3
+		 */
+		public Builder withNeo4jConversions(Neo4jConversions neo4jConversions) {
+			this.neo4jConversions = neo4jConversions;
+			return this;
+		}
+
 		public Neo4jClient build() {
 			return new DefaultNeo4jClient(this);
 		}

src/main/java/org/springframework/data/neo4j/core/ReactiveNeo4jClient.java

@@ -32,6 +32,7 @@
 import org.neo4j.driver.types.TypeSystem;
 import org.springframework.core.log.LogAccessor;
 import org.springframework.data.neo4j.core.Neo4jClient.BindSpec;
+import org.springframework.data.neo4j.core.convert.Neo4jConversions;
 import org.springframework.lang.Nullable;
 
 /**
@@ -78,6 +79,9 @@ class Builder {
 		@Nullable
 		ReactiveUserSelectionProvider impersonatedUserProvider;
 
+		@Nullable
+		Neo4jConversions neo4jConversions;
+
 		private Builder(Driver driver) {
 			this.driver = driver;
 		}
@@ -108,6 +112,18 @@ public Builder withUserSelectionProvider(@Nullable ReactiveUserSelectionProvider
 			return this;
 		}
 
+		/**
+		 * Configures the set of {@link Neo4jConversions} to use.
+		 *
+		 * @param neo4jConversions the set of conversions to use, can be {@literal null}, in this case the default set is used.
+		 * @return The builder
+		 * @since 6.3.3
+		 */
+		public Builder withNeo4jConversions(Neo4jConversions neo4jConversions) {
+			this.neo4jConversions = neo4jConversions;
+			return this;
+		}
+
 		public ReactiveNeo4jClient build() {
 			return new DefaultReactiveNeo4jClient(this);
 		}

src/test/java/org/springframework/data/neo4j/integration/conversion_imperative/TypeConversionIT.java

@@ -45,14 +45,17 @@
 import org.neo4j.driver.Session;
 import org.neo4j.driver.Value;
 import org.neo4j.driver.Values;
+import org.springframework.beans.factory.ObjectProvider;
 import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
 import org.springframework.core.convert.ConversionService;
 import org.springframework.core.convert.support.DefaultConversionService;
 import org.springframework.data.mapping.MappingException;
 import org.springframework.data.neo4j.core.DatabaseSelectionProvider;
+import org.springframework.data.neo4j.core.Neo4jClient;
 import org.springframework.data.neo4j.core.Neo4jTemplate;
+import org.springframework.data.neo4j.core.UserSelectionProvider;
 import org.springframework.data.neo4j.core.convert.Neo4jConversions;
 import org.springframework.data.neo4j.core.transaction.Neo4jBookmarkManager;
 import org.springframework.data.neo4j.core.transaction.Neo4jTransactionManager;
@@ -276,6 +279,14 @@ void nonExistingPrimitivesShouldNotFailWithFieldAccess(@Autowired Neo4jTemplate
 		});
 	}
 
+	@Test // GH-2594
+	void clientShouldUseCustomType(@Autowired Neo4jClient client) {
+
+		Optional<ThingWithCustomTypes.CustomType> value = client.query("RETURN 'whatever'")
+				.fetchAs(ThingWithCustomTypes.CustomType.class).first();
+		assertThat(value).map(ThingWithCustomTypes.CustomType::getValue).hasValue("whatever");
+	}
+
 	public interface ConvertedIDsRepository extends Neo4jRepository<ThingWithUUIDID, UUID> {
 	}
 
@@ -298,6 +309,9 @@ public interface CustomTypesRepository extends Neo4jRepository<ThingWithCustomTy
 	@EnableTransactionManagement
 	static class Config extends Neo4jImperativeTestConfiguration {
 
+		@Autowired
+		private ObjectProvider<UserSelectionProvider> userSelectionProviders;
+
 		@Bean
 		public Driver driver() {
 			return neo4jConnectionSupport.getDriver();
@@ -308,6 +322,16 @@ public Neo4jConversions neo4jConversions() {
 			return new Neo4jConversions(Collections.singleton(new ThingWithCustomTypes.CustomTypeConverter()));
 		}
 
+		@Override
+		public Neo4jClient neo4jClient(Driver driver, DatabaseSelectionProvider databaseSelectionProvider) {
+
+			return Neo4jClient.with(driver)
+					.withDatabaseSelectionProvider(databaseSelectionProvider)
+					.withUserSelectionProvider(userSelectionProviders.getIfUnique())
+					.withNeo4jConversions(neo4jConversions())
+					.build();
+		}
+
 		@Bean
 		public BookmarkCapture bookmarkCapture() {
 			return Neo4jConversionsITBase.bookmarkCapture;

src/test/java/org/springframework/data/neo4j/integration/conversion_reactive/ReactiveTypeConversionIT.java

@@ -17,6 +17,10 @@
 
 import static org.assertj.core.api.Assertions.assertThat;
 
+import org.springframework.beans.factory.ObjectProvider;
+import org.springframework.data.neo4j.core.ReactiveDatabaseSelectionProvider;
+import org.springframework.data.neo4j.core.ReactiveNeo4jClient;
+import org.springframework.data.neo4j.core.ReactiveUserSelectionProvider;
 import org.springframework.data.neo4j.test.Neo4jReactiveTestConfiguration;
 import reactor.core.publisher.Flux;
 import reactor.test.StepVerifier;
@@ -79,13 +83,28 @@ void relatedIdsShouldBeConverted(@Autowired ConvertedIDsRepository repository) {
 				.expectNextCount(2L).verifyComplete();
 	}
 
+	@Test // GH-2594
+	void clientShouldUseCustomType(@Autowired ReactiveNeo4jClient client) {
+
+		client.query("RETURN 'whatever'")
+				.fetchAs(ThingWithCustomTypes.CustomType.class)
+				.first()
+				.map(ThingWithCustomTypes.CustomType::getValue)
+				.as(StepVerifier::create)
+				.expectNext("whatever")
+				.verifyComplete();
+	}
+
 	public interface ConvertedIDsRepository extends ReactiveNeo4jRepository<ThingWithUUIDID, UUID> {}
 
 	@Configuration
 	@EnableReactiveNeo4jRepositories(considerNestedRepositories = true)
 	@EnableTransactionManagement
 	static class Config extends Neo4jReactiveTestConfiguration {
 
+		@Autowired
+		private ObjectProvider<ReactiveUserSelectionProvider> userSelectionProviders;
+
 		@Bean
 		public Driver driver() {
 			return neo4jConnectionSupport.getDriver();
@@ -100,5 +119,15 @@ public Neo4jConversions neo4jConversions() {
 		public boolean isCypher5Compatible() {
 			return neo4jConnectionSupport.isCypher5SyntaxCompatible();
 		}
+
+		@Override
+		public ReactiveNeo4jClient neo4jClient(Driver driver, ReactiveDatabaseSelectionProvider databaseSelectionProvider) {
+
+			return ReactiveNeo4jClient.with(driver)
+					.withDatabaseSelectionProvider(databaseSelectionProvider)
+					.withUserSelectionProvider(userSelectionProviders.getIfUnique())
+					.withNeo4jConversions(neo4jConversions())
+					.build();
+		}
 	}
 }