embedded replica set mongo for test

EmbeddedMongoConfig.java

import com.mongodb.client.MongoClient;
import com.mongodb.client.MongoClients;
import de.flapdoodle.embed.mongo.MongodExecutable;
import de.flapdoodle.embed.mongo.MongodProcess;
import de.flapdoodle.embed.mongo.MongodStarter;
import de.flapdoodle.embed.mongo.config.MongoCmdOptions;
import de.flapdoodle.embed.mongo.config.MongodConfig;
import de.flapdoodle.embed.mongo.config.Net;
import de.flapdoodle.embed.mongo.config.Storage;
import de.flapdoodle.embed.mongo.distribution.Version;
import de.flapdoodle.embed.process.runtime.Network;
import org.bson.Document;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.boot.test.context.TestConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.data.mongodb.core.MongoTemplate;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import java.io.IOException;

@TestConfiguration
public class EmbeddedMongoConfig {

    @Value("${spring.data.mongodb.database:my_db}")
    private String mongoDbName;

    @Value("${spring.data.mongodb.port:27018}")
    private Integer port;

    private static final String IP = "localhost";

    private MongoClient client;

    private MongodExecutable mongodExecutable;

    // This variable is defined so that different test profiles use the same mongo configuration
    private static boolean isRunning = false;

    @PostConstruct
    public void createMongoDB() throws IOException {
        String mongoUri = "mongodb://" + IP + ":" + port;

        if (!isRunning) {
            MongoCmdOptions cmdOptions = MongoCmdOptions.builder()
                    .useNoPrealloc(false)
                    .useSmallFiles(false)
                    .isVerbose(false)
                    .master(false)
                    .useNoJournal(false)
                    .syncDelay(0)
                    .build();

            MongodConfig mongodConfig = MongodConfig.builder().version(Version.Main.PRODUCTION)
                    .net(new Net(IP, port, Network.localhostIsIPv6()))
                    .replication(new Storage(null, "testRepSet", 5000))
                    .cmdOptions(cmdOptions)
                    .putParams("maxTransactionLockRequestTimeoutMillis", "100")
                    .build();

            MongodStarter starter = MongodStarter.getDefaultInstance();
            mongodExecutable = starter.prepare(mongodConfig);
            mongodExecutable.start();
            isRunning = true;
        }
        client = MongoClients.create(mongoUri);

        try {
            client.getDatabase("admin").runCommand(new Document("replSetInitiate", new Document()));
        } catch (Exception e) {
            System.out.println(e.getMessage());
        }
    }

    @PreDestroy
    public void onDestroy() {
        if (mongodExecutable != null) {
            mongodExecutable.stop();
        }
    }

    @Bean(name = "mongoTestTemplate")
    public MongoTemplate mongoTemplateTest() {
        return new MongoTemplate(client, mongoDbName);
    }

    @Bean(destroyMethod = "stop")
    public MongodProcess mongodProcess(MongodExecutable mongodExecutable) throws IOException {
        return mongodExecutable.start();
    }

    @Bean(destroyMethod = "stop")
    public MongodExecutable mongodExecutable(MongodStarter mongodStarter, MongodConfig mongodConfig) {
        return mongodStarter.prepare(mongodConfig);
    }

    @Bean
    public MongodConfig mongodConfig() {
        return MongodConfig.builder().version(Version.Main.PRODUCTION).build();
    }

    @Bean
    public MongodStarter mongodStarter() {
        return MongodStarter.getDefaultInstance();
    }
}