GH-2102 - Add user agent to transaction meta data.

Closes #2102.

Author: michael-simons

src/main/java/org/springframework/data/neo4j/core/support/UserAgent.java

@@ -0,0 +1,98 @@
+/*
+ * Copyright 2011-2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.neo4j.core.support;
+
+import org.neo4j.driver.Driver;
+import org.springframework.data.mapping.context.AbstractMappingContext;
+import org.springframework.data.neo4j.repository.config.EnableNeo4jRepositories;
+import org.springframework.lang.Nullable;
+
+/**
+ * Representation of a user agent containing sensible information to identify queries generated by or executed via Spring Data Neo4j.
+ *
+ * @author Michael J. Simons
+ * @since 6.1.11
+ */
+public enum UserAgent {
+
+	INSTANCE(
+			getVersionOf(Driver.class),
+			getVersionOf(AbstractMappingContext.class),
+			getVersionOf(EnableNeo4jRepositories.class)
+	);
+
+	@Nullable
+	private final String driverVersion;
+
+	@Nullable
+	private final String springDataVersion;
+
+	@Nullable
+	private final String sdnVersion;
+
+	private final String representation;
+
+	UserAgent(@Nullable String driverVersion, @Nullable String springDataVersion, @Nullable String sdnVersion) {
+		int idxOfDash = driverVersion == null ? -1 : driverVersion.indexOf('-');
+		this.driverVersion = driverVersion == null ?
+				null :
+				driverVersion.substring(0, idxOfDash > 0 ? idxOfDash : driverVersion.length());
+		this.springDataVersion = springDataVersion;
+		this.sdnVersion = sdnVersion;
+
+		String unknown = "-";
+		this.representation = String.format("Java/%s (%s %s %s) neo4j-java/%s spring-data/%s spring-data-neo4j/%s",
+				System.getProperty("java.version"),
+				System.getProperty("java.vm.vendor"),
+				System.getProperty("java.vm.name"),
+				System.getProperty("java.vm.version"),
+				this.driverVersion == null ? unknown : this.driverVersion,
+				this.springDataVersion == null ? unknown : this.springDataVersion,
+				this.sdnVersion == null ? unknown : this.sdnVersion
+		);
+	}
+
+	@Nullable
+	public String getDriverVersion() {
+		return driverVersion;
+	}
+
+	@Nullable
+	public String getSpringDataVersion() {
+		return springDataVersion;
+	}
+
+	@Nullable
+	public String getSdnVersion() {
+		return sdnVersion;
+	}
+
+	@Nullable
+	private static String getVersionOf(Class<?> type) {
+
+		Package p = type.getPackage();
+		String version = p.getImplementationVersion();
+		if (!(version == null || version.trim().isEmpty())) {
+			return version;
+		}
+		return null;
+	}
+
+	@Override
+	public String toString() {
+		return this.representation;
+	}
+}

src/main/java/org/springframework/data/neo4j/core/transaction/Neo4jTransactionUtils.java

@@ -26,6 +26,7 @@
 import org.neo4j.driver.TransactionConfig;
 import org.springframework.data.neo4j.core.DatabaseSelection;
 import org.springframework.data.neo4j.core.UserSelection;
+import org.springframework.data.neo4j.core.support.UserAgent;
 import org.springframework.transaction.IllegalTransactionStateException;
 import org.springframework.transaction.InvalidIsolationLevelException;
 import org.springframework.transaction.TransactionDefinition;
@@ -111,7 +112,9 @@ static TransactionConfig createTransactionConfigFrom(TransactionDefinition defin
 			builder = builder.withTimeout(Duration.ofSeconds(defaultTxManagerTimeout));
 		}
 
-		return builder.build();
+		return builder
+				.withMetadata(Collections.singletonMap("app", UserAgent.INSTANCE.toString()))
+				.build();
 	}
 
 	static String formatOngoingTxInAnotherDbErrorMessage(

src/main/java/org/springframework/data/neo4j/repository/config/StartupLogger.java

@@ -18,9 +18,8 @@
 import java.util.Optional;
 
 import org.apache.commons.logging.LogFactory;
-import org.neo4j.driver.Driver;
 import org.springframework.core.log.LogAccessor;
-import org.springframework.data.mapping.context.AbstractMappingContext;
+import org.springframework.data.neo4j.core.support.UserAgent;
 
 /**
  * Logs startup information.
@@ -59,23 +58,18 @@ void logStarting() {
 	String getStartingMessage() {
 
 		StringBuilder sb = new StringBuilder();
+		UserAgent userAgent = UserAgent.INSTANCE;
 
-		String sdnRx = getVersionOf(EnableNeo4jRepositories.class).map(v -> "SDN v" + v)
+		String sdnRx = Optional.ofNullable(userAgent.getSdnVersion()).map(v -> "SDN v" + v)
 				.orElse("an unknown version of SDN");
-		String sdC = getVersionOf(AbstractMappingContext.class).map(v -> "Spring Data Commons v" + v)
+		String sdC = Optional.ofNullable(userAgent.getSpringDataVersion()).map(v -> "Spring Data Commons v" + v)
 				.orElse("an unknown version of Spring Data Commons");
-		String driver = getVersionOf(Driver.class).map(v -> "Neo4j Driver v" + v)
+		String driver = Optional.ofNullable(userAgent.getDriverVersion()).map(v -> "Neo4j Driver v" + v)
 				.orElse("an unknown version of the Neo4j Java Driver");
 
 		sb.append("Bootstrapping ").append(mode.displayValue).append(" Neo4j repositories based on ").append(sdnRx)
 				.append(" with ").append(sdC).append(" and ").append(driver).append(".");
 
 		return sb.toString();
 	}
-
-	private Optional<String> getVersionOf(Class<?> clazz) {
-
-		return Optional.of(clazz).map(Class::getPackage).map(Package::getImplementationVersion).map(String::trim)
-				.filter(v -> !v.isEmpty());
-	}
 }

src/test/java/org/springframework/data/neo4j/core/support/UserAgentTest.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright 2011-2022 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.neo4j.core.support;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+import org.junit.jupiter.api.Test;
+
+/**
+ * @author Michael J. Simons
+ */
+class UserAgentTest {
+
+	@Test
+	void toStringShouldWork() {
+
+		assertThat(UserAgent.INSTANCE.toString())
+				.matches("Java/.+ \\(.+\\) neo4j-java/.+ spring-data/.+ spring-data-neo4j/.+");
+	}
+}