ac.simons.neo4j.migrations.core.HBD Maven / Gradle / Ivy

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/*
 * Copyright 2020-2022 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 ac.simons.neo4j.migrations.core;

import ac.simons.neo4j.migrations.core.internal.Neo4jVersionComparator;

import java.util.function.Supplier;

import org.neo4j.driver.Session;
import org.neo4j.driver.exceptions.ClientException;
import org.neo4j.driver.exceptions.Neo4jException;

/**
 * Some utilities to deal with Neo4j quirks. Stay away, here be dragons.
 *
 * @author Michael J. Simons
 * @soundtrack Guns n' Roses - Appetite For Democracy 3D
 * @since 1.4.0
 */
final class HBD {

	static boolean is4xSeries(ConnectionDetails connectionDetails) {
		return connectionDetails.getServerVersion() != null && connectionDetails.getServerVersion()
			.replaceFirst("(?i)^Neo4j/", "").matches("^4\\.?.*");
	}

	static boolean is44OrHigher(ConnectionDetails connectionDetails) {

		if (connectionDetails.getServerVersion() == null) {
			return false;
		}

		Neo4jVersionComparator versionComparator = new Neo4jVersionComparator();
		return versionComparator.compare(connectionDetails.getServerVersion(), "4.4") >= 0;
	}

	static Integer silentCreateConstraint(ConnectionDetails connectionDetails, Session session, String statement,
		String name, Supplier failureMessage) {

		String finalStatement;
		String replacement = "";
		if (is4xSeries(connectionDetails) && name != null && !name.trim().isEmpty()) {
			replacement = name.trim() + " ";
		}
		finalStatement = statement.replace("$name ", replacement);

		try {
			return session.writeTransaction(tx -> tx.run(finalStatement).consume().counters().constraintsAdded());
		} catch (Neo4jException e) {

			if (!Neo4jCodes.CODES_FOR_EXISTING_CONSTRAINT.contains(e.code())) {
				throw new MigrationsException(failureMessage.get(), e);
			}
		}

		return 0;
	}

	static Integer silentDropConstraint(ConnectionDetails connectionDetails, Session session, String statement,
		String name) {

		String finalStatement;
		if (is4xSeries(connectionDetails) && name != null && !name.trim().isEmpty()) {
			finalStatement = "DROP CONSTRAINT " + name.trim();
		} else {
			finalStatement = statement;
		}

		try {
			return session.writeTransaction(tx ->
				tx.run(finalStatement).consume().counters().constraintsRemoved());
		} catch (Neo4jException e) {
			if (!Neo4jCodes.CONSTRAINT_DROP_FAILED.equals(e.code())) {
				throw new MigrationsException("Could not remove locks", e);
			}
		}

		return 0;
	}

	static boolean constraintWithNameAlreadyExists(MigrationsException e) {
		return e != null && e.getCause() instanceof ClientException && Neo4jCodes.CONSTRAINT_WITH_NAME_ALREADY_EXISTS_CODE.equals(
			((ClientException) e.getCause()).code());
	}

	private HBD() {
	}
}