Working with NoSQL Technologies

Spring Data provides additional projects that help you access a variety of NoSQL technologies, including:

Of these, Spring Boot provides auto-configuration for Cassandra, Couchbase, Elasticsearch, LDAP, MongoDB, Neo4J and Redis. Additionally, Spring Boot for Apache Geode provides auto-configuration for Apache Geode. You can make use of the other projects, but you must configure them yourself. See the appropriate reference documentation at spring.io/projects/spring-data.

Spring Boot also provides auto-configuration for the InfluxDB client but it is deprecated in favor of the new InfluxDB Java client that provides its own Spring Boot integration.

Redis

Redis is a cache, message broker, and richly-featured key-value store. Spring Boot offers basic auto-configuration for the Lettuce and Jedis client libraries and the abstractions on top of them provided by Spring Data Redis.

There is a spring-boot-starter-data-redis starter for collecting the dependencies in a convenient way. By default, it uses Lettuce. That starter handles both traditional and reactive applications.

We also provide a spring-boot-starter-data-redis-reactive starter for consistency with the other stores with reactive support.

Connecting to Redis

You can inject an auto-configured RedisConnectionFactory, StringRedisTemplate, or vanilla RedisTemplate instance as you would any other Spring Bean. The following listing shows an example of such a bean:

Java
Kotlin

import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

@Component
public class MyBean {

	private final StringRedisTemplate template;

	public MyBean(StringRedisTemplate template) {
		this.template = template;
	}

	// ...

	public Boolean someMethod() {
		return this.template.hasKey("spring");
	}

}

import org.springframework.data.redis.core.StringRedisTemplate
import org.springframework.stereotype.Component

@Component
class MyBean(private val template: StringRedisTemplate) {

	// ...

	fun someMethod(): Boolean {
		return template.hasKey("spring")
	}

}

By default, the instance tries to connect to a Redis server at localhost:6379. You can specify custom connection details using spring.data.redis.* properties, as shown in the following example:

Properties
YAML

spring.data.redis.host=localhost
spring.data.redis.port=6379
spring.data.redis.database=0
spring.data.redis.username=user
spring.data.redis.password=secret

spring:
  data:
    redis:
      host: "localhost"
      port: 6379
      database: 0
      username: "user"
      password: "secret"

You can also specify the url of the Redis server directly. When setting the url, the host, port, username and password properties are ignored. This is shown in the following example:

Properties
YAML

spring.data.redis.url=redis://user:secret@localhost:6379
spring.data.redis.database=0

spring:
  data:
    redis:
      url: "redis://user:secret@localhost:6379"
      database: 0

You can also register an arbitrary number of beans that implement LettuceClientConfigurationBuilderCustomizer for more advanced customizations. ClientResources can also be customized using ClientResourcesBuilderCustomizer. If you use Jedis, JedisClientConfigurationBuilderCustomizer is also available. Alternatively, you can register a bean of type RedisStandaloneConfiguration, RedisSentinelConfiguration, or RedisClusterConfiguration to take full control over the configuration.

If you add your own @Bean of any of the auto-configured types, it replaces the default (except in the case of RedisTemplate, when the exclusion is based on the bean name, redisTemplate, not its type).

By default, a pooled connection factory is auto-configured if commons-pool2 is on the classpath.

The auto-configured RedisConnectionFactory can be configured to use SSL for communication with the server by setting the properties as shown in this example:

Properties
YAML

spring.data.redis.ssl.enabled=true

spring:
  data:
    redis:
      ssl:
        enabled: true

Custom SSL trust material can be configured in an SSL bundle and applied to the RedisConnectionFactory as shown in this example:

Properties
YAML

spring.data.redis.ssl.bundle=example

spring:
  data:
    redis:
      ssl:
        bundle: "example"

MongoDB

MongoDB is an open-source NoSQL document database that uses a JSON-like schema instead of traditional table-based relational data. Spring Boot offers several conveniences for working with MongoDB, including the spring-boot-starter-data-mongodb and spring-boot-starter-data-mongodb-reactive starters.

Connecting to a MongoDB Database

To access MongoDB databases, you can inject an auto-configured MongoDatabaseFactory. By default, the instance tries to connect to a MongoDB server at mongodb://localhost/test. The following example shows how to connect to a MongoDB database:

Java
Kotlin

import com.mongodb.client.MongoCollection;
import com.mongodb.client.MongoDatabase;
import org.bson.Document;

import org.springframework.data.mongodb.MongoDatabaseFactory;
import org.springframework.stereotype.Component;

@Component
public class MyBean {

	private final MongoDatabaseFactory mongo;

	public MyBean(MongoDatabaseFactory mongo) {
		this.mongo = mongo;
	}

	// ...

	public MongoCollection<Document> someMethod() {
		MongoDatabase db = this.mongo.getMongoDatabase();
		return db.getCollection("users");
	}

}

import com.mongodb.client.MongoCollection
import org.bson.Document
import org.springframework.data.mongodb.MongoDatabaseFactory
import org.springframework.stereotype.Component

@Component
class MyBean(private val mongo: MongoDatabaseFactory) {

	// ...

	fun someMethod(): MongoCollection<Document> {
		val db = mongo.mongoDatabase
		return db.getCollection("users")
	}

}

If you have defined your own MongoClient, it will be used to auto-configure a suitable MongoDatabaseFactory.

The auto-configured MongoClient is created using a MongoClientSettings bean. If you have defined your own MongoClientSettings, it will be used without modification and the spring.data.mongodb properties will be ignored. Otherwise a MongoClientSettings will be auto-configured and will have the spring.data.mongodb properties applied to it. In either case, you can declare one or more MongoClientSettingsBuilderCustomizer beans to fine-tune the MongoClientSettings configuration. Each will be called in order with the MongoClientSettings.Builder that is used to build the MongoClientSettings.

You can set the spring.data.mongodb.uri property to change the URL and configure additional settings such as the replica set, as shown in the following example:

Properties
YAML

spring.data.mongodb.uri=mongodb://user:[email protected]:27017,mongoserver2.example.com:23456/test

spring:
  data:
    mongodb:
      uri: "mongodb://user:[email protected]:27017,mongoserver2.example.com:23456/test"

Alternatively, you can specify connection details using discrete properties. For example, you might declare the following settings in your application.properties:

Properties
YAML

spring.data.mongodb.host=mongoserver1.example.com
spring.data.mongodb.port=27017
spring.data.mongodb.additional-hosts[0]=mongoserver2.example.com:23456
spring.data.mongodb.database=test
spring.data.mongodb.username=user
spring.data.mongodb.password=secret

spring:
  data:
    mongodb:
      host: "mongoserver1.example.com"
      port: 27017
      additional-hosts:
      - "mongoserver2.example.com:23456"
      database: "test"
      username: "user"
      password: "secret"

The auto-configured MongoClient can be configured to use SSL for communication with the server by setting the properties as shown in this example:

Properties
YAML

spring.data.mongodb.uri=mongodb://user:[email protected]:27017,mongoserver2.example.com:23456/test
spring.data.mongodb.ssl.enabled=true

spring:
  data:
    mongodb:
      uri: "mongodb://user:[email protected]:27017,mongoserver2.example.com:23456/test"
      ssl:
        enabled: true

Custom SSL trust material can be configured in an SSL bundle and applied to the MongoClient as shown in this example:

Properties
YAML

spring.data.mongodb.uri=mongodb://user:[email protected]:27017,mongoserver2.example.com:23456/test
spring.data.mongodb.ssl.bundle=example

spring:
  data:
    mongodb:
      uri: "mongodb://user:[email protected]:27017,mongoserver2.example.com:23456/test"
      ssl:
        bundle: "example"

If spring.data.mongodb.port is not specified, the default of 27017 is used. You could delete this line from the example shown earlier.

You can also specify the port as part of the host address by using the host:port syntax. This format should be used if you need to change the port of an additional-hosts entry.

If you do not use Spring Data MongoDB, you can inject a MongoClient bean instead of using MongoDatabaseFactory. If you want to take complete control of establishing the MongoDB connection, you can also declare your own MongoDatabaseFactory or MongoClient bean.

If you are using the reactive driver, Netty is required for SSL. The auto-configuration configures this factory automatically if Netty is available and the factory to use has not been customized already.

MongoTemplate

Spring Data MongoDB provides a MongoTemplate class that is very similar in its design to Spring’s JdbcTemplate. As with JdbcTemplate, Spring Boot auto-configures a bean for you to inject the template, as follows:

Java
Kotlin

import com.mongodb.client.MongoCollection;
import org.bson.Document;

import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.stereotype.Component;

@Component
public class MyBean {

	private final MongoTemplate mongoTemplate;

	public MyBean(MongoTemplate mongoTemplate) {
		this.mongoTemplate = mongoTemplate;
	}

	// ...

	public MongoCollection<Document> someMethod() {
		return this.mongoTemplate.getCollection("users");
	}

}

import com.mongodb.client.MongoCollection
import org.bson.Document
import org.springframework.data.mongodb.core.MongoTemplate
import org.springframework.stereotype.Component

@Component
class MyBean(private val mongoTemplate: MongoTemplate) {

	// ...

	fun someMethod(): MongoCollection<Document> {
		return mongoTemplate.getCollection("users")
	}

}

See the MongoOperations API documentation for complete details.

Spring Data MongoDB Repositories

Spring Data includes repository support for MongoDB. As with the JPA repositories discussed earlier, the basic principle is that queries are constructed automatically, based on method names.

In fact, both Spring Data JPA and Spring Data MongoDB share the same common infrastructure. You could take the JPA example from earlier and, assuming that City is now a MongoDB data class rather than a JPA @Entity, it works in the same way, as shown in the following example:

Java
Kotlin

import org.springframework.data.domain.Page;
import org.springframework.data.domain.Pageable;
import org.springframework.data.repository.Repository;

public interface CityRepository extends Repository<City, Long> {

	Page<City> findAll(Pageable pageable);

	City findByNameAndStateAllIgnoringCase(String name, String state);

}

import org.springframework.data.domain.Page
import org.springframework.data.domain.Pageable
import org.springframework.data.repository.Repository

interface CityRepository :
	Repository<City?, Long?> {
	fun findAll(pageable: Pageable?): Page<City?>?
	fun findByNameAndStateAllIgnoringCase(name: String?, state: String?): City?
}

Repositories and documents are found through scanning. By default, the auto-configuration packages are scanned. You can customize the locations to look for repositories and documents by using @EnableMongoRepositories and @EntityScan respectively.

For complete details of Spring Data MongoDB, including its rich object mapping technologies, see its reference documentation.

Neo4j

Neo4j is an open-source NoSQL graph database that uses a rich data model of nodes connected by first class relationships, which is better suited for connected big data than traditional RDBMS approaches. Spring Boot offers several conveniences for working with Neo4j, including the spring-boot-starter-data-neo4j starter.

Connecting to a Neo4j Database

To access a Neo4j server, you can inject an auto-configured Driver. By default, the instance tries to connect to a Neo4j server at localhost:7687 using the Bolt protocol. The following example shows how to inject a Neo4j Driver that gives you access, amongst other things, to a Session:

Java
Kotlin

import org.neo4j.driver.Driver;
import org.neo4j.driver.Session;
import org.neo4j.driver.Values;

import org.springframework.stereotype.Component;

@Component
public class MyBean {

	private final Driver driver;

	public MyBean(Driver driver) {
		this.driver = driver;
	}

	// ...

	public String someMethod(String message) {
		try (Session session = this.driver.session()) {
			return session.executeWrite(
					(transaction) -> transaction
						.run("CREATE (a:Greeting) SET a.message = $message RETURN a.message + ', from node ' + id(a)",
								Values.parameters("message", message))
						.single()
						.get(0)
						.asString());
		}
	}

}

import org.neo4j.driver.*
import org.springframework.stereotype.Component

@Component
class MyBean(private val driver: Driver) {
	// ...
	fun someMethod(message: String?): String {
		driver.session().use { session ->
			return@someMethod session.executeWrite { transaction: TransactionContext ->
				transaction
					.run(
						"CREATE (a:Greeting) SET a.message = \$message RETURN a.message + ', from node ' + id(a)",
						Values.parameters("message", message)
					)
					.single()[0].asString()
			}
		}
	}
}

You can configure various aspects of the driver using spring.neo4j.* properties. The following example shows how to configure the uri and credentials to use:

Properties
YAML

spring.neo4j.uri=bolt://my-server:7687
spring.neo4j.authentication.username=neo4j
spring.neo4j.authentication.password=secret

spring:
  neo4j:
    uri: "bolt://my-server:7687"
    authentication:
      username: "neo4j"
      password: "secret"

The auto-configured Driver is created using org.neo4j.driver.Config$ConfigBuilder. To fine-tune its configuration, declare one or more ConfigBuilderCustomizer beans. Each will be called in order with the org.neo4j.driver.Config$ConfigBuilder that is used to build the Driver.

Spring Data Neo4j Repositories

Spring Data includes repository support for Neo4j. For complete details of Spring Data Neo4j, see the reference documentation.

Spring Data Neo4j shares the common infrastructure with Spring Data JPA as many other Spring Data modules do. You could take the JPA example from earlier and define City as Spring Data Neo4j @Node rather than JPA @Entity and the repository abstraction works in the same way, as shown in the following example:

Java
Kotlin

import java.util.Optional;

import org.springframework.data.neo4j.repository.Neo4jRepository;

public interface CityRepository extends Neo4jRepository<City, Long> {

	Optional<City> findOneByNameAndState(String name, String state);

}

import org.springframework.data.neo4j.repository.Neo4jRepository
import java.util.Optional

interface CityRepository : Neo4jRepository<City?, Long?> {

	fun findOneByNameAndState(name: String?, state: String?): Optional<City?>?

}

The spring-boot-starter-data-neo4j starter enables the repository support as well as transaction management. Spring Boot supports both classic and reactive Neo4j repositories, using the Neo4jTemplate or ReactiveNeo4jTemplate beans. When Project Reactor is available on the classpath, the reactive style is also auto-configured.

Repositories and entities are found through scanning. By default, the auto-configuration packages are scanned. You can customize the locations to look for repositories and entities by using @EnableNeo4jRepositories and @EntityScan respectively.

In an application using the reactive style, a ReactiveTransactionManager is not auto-configured. To enable transaction management, the following bean must be defined in your configuration:

Java
Kotlin

import org.neo4j.driver.Driver;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.neo4j.core.ReactiveDatabaseSelectionProvider;
import org.springframework.data.neo4j.core.transaction.ReactiveNeo4jTransactionManager;

@Configuration(proxyBeanMethods = false)
public class MyNeo4jConfiguration {

	@Bean
	public ReactiveNeo4jTransactionManager reactiveTransactionManager(Driver driver,
			ReactiveDatabaseSelectionProvider databaseNameProvider) {
		return new ReactiveNeo4jTransactionManager(driver, databaseNameProvider);
	}

}

import org.neo4j.driver.Driver
import org.springframework.context.annotation.Bean
import org.springframework.context.annotation.Configuration
import org.springframework.data.neo4j.core.ReactiveDatabaseSelectionProvider
import org.springframework.data.neo4j.core.transaction.ReactiveNeo4jTransactionManager

@Configuration(proxyBeanMethods = false)
class MyNeo4jConfiguration {

	@Bean
	fun reactiveTransactionManager(driver: Driver,
			databaseNameProvider: ReactiveDatabaseSelectionProvider): ReactiveNeo4jTransactionManager {
		return ReactiveNeo4jTransactionManager(driver, databaseNameProvider)
	}
}

Elasticsearch

Elasticsearch is an open source, distributed, RESTful search and analytics engine. Spring Boot offers basic auto-configuration for Elasticsearch clients.

Spring Boot supports several clients:

The official low-level REST client
The official Java API client
The ReactiveElasticsearchClient provided by Spring Data Elasticsearch

Spring Boot provides a dedicated starter, spring-boot-starter-data-elasticsearch.

Connecting to Elasticsearch Using REST clients

Elasticsearch ships two different REST clients that you can use to query a cluster: the low-level client from the org.elasticsearch.client:elasticsearch-rest-client module and the Java API client from the co.elastic.clients:elasticsearch-java module. Additionally, Spring Boot provides support for a reactive client from the org.springframework.data:spring-data-elasticsearch module. By default, the clients will target localhost:9200. You can use spring.elasticsearch.* properties to further tune how the clients are configured, as shown in the following example:

Properties
YAML

spring.elasticsearch.uris=https://search.example.com:9200
spring.elasticsearch.socket-timeout=10s
spring.elasticsearch.username=user
spring.elasticsearch.password=secret

spring:
  elasticsearch:
    uris: "https://search.example.com:9200"
    socket-timeout: "10s"
    username: "user"
    password: "secret"

Connecting to Elasticsearch Using RestClient

If you have elasticsearch-rest-client on the classpath, Spring Boot will auto-configure and register a RestClient bean. In addition to the properties described previously, to fine-tune the RestClient you can register an arbitrary number of beans that implement RestClientBuilderCustomizer for more advanced customizations. To take full control over the clients' configuration, define a RestClientBuilder bean.

Additionally, if elasticsearch-rest-client-sniffer is on the classpath, a Sniffer is auto-configured to automatically discover nodes from a running Elasticsearch cluster and set them on the RestClient bean. You can further tune how Sniffer is configured, as shown in the following example:

Properties
YAML

spring.elasticsearch.restclient.sniffer.interval=10m
spring.elasticsearch.restclient.sniffer.delay-after-failure=30s

spring:
  elasticsearch:
    restclient:
      sniffer:
        interval: "10m"
        delay-after-failure: "30s"

Connecting to Elasticsearch Using ElasticsearchClient

If you have co.elastic.clients:elasticsearch-java on the classpath, Spring Boot will auto-configure and register an ElasticsearchClient bean.

The ElasticsearchClient uses a transport that depends upon the previously described RestClient. Therefore, the properties described previously can be used to configure the ElasticsearchClient. Furthermore, you can define a RestClientOptions bean to take further control of the behavior of the transport.

Connecting to Elasticsearch using ReactiveElasticsearchClient

Spring Data Elasticsearch ships ReactiveElasticsearchClient for querying Elasticsearch instances in a reactive fashion. If you have Spring Data Elasticsearch and Reactor on the classpath, Spring Boot will auto-configure and register a ReactiveElasticsearchClient.

The ReactiveElasticsearchClient uses a transport that depends upon the previously described RestClient. Therefore, the properties described previously can be used to configure the ReactiveElasticsearchClient. Furthermore, you can define a RestClientOptions bean to take further control of the behavior of the transport.

Connecting to Elasticsearch by Using Spring Data

To connect to Elasticsearch, an ElasticsearchClient bean must be defined, auto-configured by Spring Boot or manually provided by the application (see previous sections). With this configuration in place, an ElasticsearchTemplate can be injected like any other Spring bean, as shown in the following example:

Java
Kotlin

import org.springframework.data.elasticsearch.client.elc.ElasticsearchTemplate;
import org.springframework.stereotype.Component;

@Component
public class MyBean {

	private final ElasticsearchTemplate template;

	public MyBean(ElasticsearchTemplate template) {
		this.template = template;
	}

	// ...

	public boolean someMethod(String id) {
		return this.template.exists(id, User.class);
	}

}

import org.springframework.stereotype.Component

@Component
class MyBean(private val template: org.springframework.data.elasticsearch.client.elc.ElasticsearchTemplate ) {

	// ...

	fun someMethod(id: String): Boolean {
		return template.exists(id, User::class.java)
	}

}

In the presence of spring-data-elasticsearch and Reactor, Spring Boot can also auto-configure a ReactiveElasticsearchClient and a ReactiveElasticsearchTemplate as beans. They are the reactive equivalent of the other REST clients.

Spring Data Elasticsearch Repositories

Spring Data includes repository support for Elasticsearch. As with the JPA repositories discussed earlier, the basic principle is that queries are constructed for you automatically based on method names.

In fact, both Spring Data JPA and Spring Data Elasticsearch share the same common infrastructure. You could take the JPA example from earlier and, assuming that City is now an Elasticsearch @Document class rather than a JPA @Entity, it works in the same way.

For complete details of Spring Data Elasticsearch, see the reference documentation.

Spring Boot supports both classic and reactive Elasticsearch repositories, using the ElasticsearchTemplate or ReactiveElasticsearchTemplate beans. Most likely those beans are auto-configured by Spring Boot given the required dependencies are present.

If you wish to use your own template for backing the Elasticsearch repositories, you can add your own ElasticsearchTemplate or ElasticsearchOperations @Bean, as long as it is named "elasticsearchTemplate". Same applies to ReactiveElasticsearchTemplate and ReactiveElasticsearchOperations, with the bean name "reactiveElasticsearchTemplate".

You can choose to disable the repositories support with the following property:

Properties
YAML

spring.data.elasticsearch.repositories.enabled=false

spring:
  data:
    elasticsearch:
      repositories:
        enabled: false

Cassandra

Cassandra is an open source, distributed database management system designed to handle large amounts of data across many commodity servers. Spring Boot offers auto-configuration for Cassandra and the abstractions on top of it provided by Spring Data Cassandra. There is a spring-boot-starter-data-cassandra starter for collecting the dependencies in a convenient way.

Connecting to Cassandra

You can inject an auto-configured CassandraTemplate or a Cassandra CqlSession instance as you would with any other Spring Bean. The spring.cassandra.* properties can be used to customize the connection. Generally, you provide keyspace-name and contact-points as well the local datacenter name, as shown in the following example:

Properties
YAML

spring.cassandra.keyspace-name=mykeyspace
spring.cassandra.contact-points=cassandrahost1:9042,cassandrahost2:9042
spring.cassandra.local-datacenter=datacenter1

spring:
  cassandra:
    keyspace-name: "mykeyspace"
    contact-points: "cassandrahost1:9042,cassandrahost2:9042"
    local-datacenter: "datacenter1"

If the port is the same for all your contact points you can use a shortcut and only specify the host names, as shown in the following example:

Properties
YAML

spring.cassandra.keyspace-name=mykeyspace
spring.cassandra.contact-points=cassandrahost1,cassandrahost2
spring.cassandra.local-datacenter=datacenter1

spring:
  cassandra:
    keyspace-name: "mykeyspace"
    contact-points: "cassandrahost1,cassandrahost2"
    local-datacenter: "datacenter1"

Those two examples are identical as the port default to 9042. If you need to configure the port, use spring.cassandra.port.

The auto-configured CqlSession can be configured to use SSL for communication with the server by setting the properties as shown in this example:

Properties
YAML

spring.cassandra.keyspace-name=mykeyspace
spring.cassandra.contact-points=cassandrahost1,cassandrahost2
spring.cassandra.local-datacenter=datacenter1
spring.cassandra.ssl.enabled=true

spring:
  cassandra:
    keyspace-name: "mykeyspace"
    contact-points: "cassandrahost1,cassandrahost2"
    local-datacenter: "datacenter1"
    ssl:
      enabled: true

Custom SSL trust material can be configured in an SSL bundle and applied to the CqlSession as shown in this example:

Properties
YAML

spring.cassandra.keyspace-name=mykeyspace
spring.cassandra.contact-points=cassandrahost1,cassandrahost2
spring.cassandra.local-datacenter=datacenter1
spring.cassandra.ssl.bundle=example

spring:
  cassandra:
    keyspace-name: "mykeyspace"
    contact-points: "cassandrahost1,cassandrahost2"
    local-datacenter: "datacenter1"
    ssl:
      bundle: "example"

The Cassandra driver has its own configuration infrastructure that loads an application.conf at the root of the classpath.

Spring Boot does not look for such a file by default but can load one using spring.cassandra.config. If a property is both present in spring.cassandra.* and the configuration file, the value in spring.cassandra.* takes precedence.

For more advanced driver customizations, you can register an arbitrary number of beans that implement DriverConfigLoaderBuilderCustomizer. The CqlSession can be customized with a bean of type CqlSessionBuilderCustomizer.

If you use CqlSessionBuilder to create multiple CqlSession beans, keep in mind the builder is mutable so make sure to inject a fresh copy for each session.

The following code listing shows how to inject a Cassandra bean:

Java
Kotlin

import org.springframework.data.cassandra.core.CassandraTemplate;
import org.springframework.stereotype.Component;

@Component
public class MyBean {

	private final CassandraTemplate template;

	public MyBean(CassandraTemplate template) {
		this.template = template;
	}

	// ...

	public long someMethod() {
		return this.template.count(User.class);
	}

}

import org.springframework.data.cassandra.core.CassandraTemplate
import org.springframework.stereotype.Component

@Component
class MyBean(private val template: CassandraTemplate) {

	// ...

	fun someMethod(): Long {
		return template.count(User::class.java)
	}

}

If you add your own @Bean of type CassandraTemplate, it replaces the default.

Spring Data Cassandra Repositories

Spring Data includes basic repository support for Cassandra. Currently, this is more limited than the JPA repositories discussed earlier and needs @Query annotated finder methods.

For complete details of Spring Data Cassandra, see the reference documentation.

Couchbase

Couchbase is an open-source, distributed, multi-model NoSQL document-oriented database that is optimized for interactive applications. Spring Boot offers auto-configuration for Couchbase and the abstractions on top of it provided by Spring Data Couchbase. There are spring-boot-starter-data-couchbase and spring-boot-starter-data-couchbase-reactive starters for collecting the dependencies in a convenient way.

Connecting to Couchbase

You can get a Cluster by adding the Couchbase SDK and some configuration. The spring.couchbase.* properties can be used to customize the connection. Generally, you provide the connection string and credentials for authentication. Basic authentication with username and password can be configured as shown in the following example:

Properties
YAML

spring.couchbase.connection-string=couchbase://192.168.1.123
spring.couchbase.username=user
spring.couchbase.password=secret

spring:
  couchbase:
    connection-string: "couchbase://192.168.1.123"
    username: "user"
    password: "secret"

Client certificates can be used for authentication instead of username and password. The location and password for a Java KeyStore containing client certificates can be configured as shown in the following example:

Properties
YAML

spring.couchbase.connection-string=couchbase://192.168.1.123
spring.couchbase.env.ssl.enabled=true
spring.couchbase.authentication.jks.location=classpath:client.p12
spring.couchbase.authentication.jks.password=secret

spring:
  couchbase:
    connection-string: "couchbase://192.168.1.123"
    env:
      ssl:
        enabled: true
    authentication:
      jks:
        location: "classpath:client.p12"
        password: "secret"

PEM-encoded certificates and a private key can be configured as shown in the following example:

Properties
YAML

spring.couchbase.connection-string=couchbase://192.168.1.123
spring.couchbase.env.ssl.enabled=true
spring.couchbase.authentication.pem.certificates=classpath:client.crt
spring.couchbase.authentication.pem.private-key=classpath:client.key

spring:
  couchbase:
    connection-string: "couchbase://192.168.1.123"
    env:
      ssl:
        enabled: true
    authentication:
      pem:
        certificates: "classpath:client.crt"
        private-key: "classpath:client.key"

It is also possible to customize some of the ClusterEnvironment settings. For instance, the following configuration changes the timeout to open a new Bucket and enables SSL support with a reference to a configured SSL bundle:

Properties
YAML

spring.couchbase.env.timeouts.connect=3s
spring.couchbase.env.ssl.bundle=example

spring:
  couchbase:
    env:
      timeouts:
        connect: "3s"
      ssl:
        bundle: "example"

Check the spring.couchbase.env.* properties for more details. To take more control, one or more ClusterEnvironmentBuilderCustomizer beans can be used.

Spring Data Couchbase Repositories

Spring Data includes repository support for Couchbase.

For complete details of Spring Data Couchbase, see the reference documentation.

You can inject an auto-configured CouchbaseTemplate instance as you would with any other Spring Bean, provided a CouchbaseClientFactory bean is available. This happens when a Cluster is available, as described above, and a bucket name has been specified:

Properties
YAML

spring.data.couchbase.bucket-name=my-bucket

spring:
  data:
    couchbase:
      bucket-name: "my-bucket"

The following examples shows how to inject a CouchbaseTemplate bean:

Java
Kotlin

import org.springframework.data.couchbase.core.CouchbaseTemplate;
import org.springframework.stereotype.Component;

@Component
public class MyBean {

	private final CouchbaseTemplate template;

	public MyBean(CouchbaseTemplate template) {
		this.template = template;
	}

	// ...

	public String someMethod() {
		return this.template.getBucketName();
	}

}

import org.springframework.data.couchbase.core.CouchbaseTemplate
import org.springframework.stereotype.Component

@Component
class MyBean(private val template: CouchbaseTemplate) {

	// ...

	fun someMethod(): String {
		return template.bucketName
	}

}

There are a few beans that you can define in your own configuration to override those provided by the auto-configuration:

A CouchbaseMappingContext @Bean with a name of couchbaseMappingContext.
A CustomConversions @Bean with a name of couchbaseCustomConversions.
A CouchbaseTemplate @Bean with a name of couchbaseTemplate.

To avoid hard-coding those names in your own config, you can reuse BeanNames provided by Spring Data Couchbase. For instance, you can customize the converters to use, as follows:

Java
Kotlin

import org.assertj.core.util.Arrays;

import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.data.couchbase.config.BeanNames;
import org.springframework.data.couchbase.core.convert.CouchbaseCustomConversions;

@Configuration(proxyBeanMethods = false)
public class MyCouchbaseConfiguration {

	@Bean(BeanNames.COUCHBASE_CUSTOM_CONVERSIONS)
	public CouchbaseCustomConversions myCustomConversions() {
		return new CouchbaseCustomConversions(Arrays.asList(new MyConverter()));
	}

}

import org.assertj.core.util.Arrays
import org.springframework.context.annotation.Bean
import org.springframework.context.annotation.Configuration
import org.springframework.data.couchbase.config.BeanNames
import org.springframework.data.couchbase.core.convert.CouchbaseCustomConversions

@Configuration(proxyBeanMethods = false)
class MyCouchbaseConfiguration {

	@Bean(BeanNames.COUCHBASE_CUSTOM_CONVERSIONS)
	fun myCustomConversions(): CouchbaseCustomConversions {
		return CouchbaseCustomConversions(Arrays.asList(MyConverter()))
	}

}

LDAP

LDAP (Lightweight Directory Access Protocol) is an open, vendor-neutral, industry standard application protocol for accessing and maintaining distributed directory information services over an IP network. Spring Boot offers auto-configuration for any compliant LDAP server as well as support for the embedded in-memory LDAP server from UnboundID.

LDAP abstractions are provided by Spring Data LDAP. There is a spring-boot-starter-data-ldap starter for collecting the dependencies in a convenient way.

Connecting to an LDAP Server

To connect to an LDAP server, make sure you declare a dependency on the spring-boot-starter-data-ldap starter or spring-ldap-core and then declare the URLs of your server in your application.properties, as shown in the following example:

Properties
YAML

spring.ldap.urls=ldap://myserver:1235
spring.ldap.username=admin
spring.ldap.password=secret

spring:
  ldap:
    urls: "ldap://myserver:1235"
    username: "admin"
    password: "secret"

If you need to customize connection settings, you can use the spring.ldap.base and spring.ldap.base-environment properties.

An LdapContextSource is auto-configured based on these settings. If a DirContextAuthenticationStrategy bean is available, it is associated to the auto-configured LdapContextSource. If you need to customize it, for instance to use a PooledContextSource, you can still inject the auto-configured LdapContextSource. Make sure to flag your customized ContextSource as @Primary so that the auto-configured LdapTemplate uses it.

Spring Data LDAP Repositories

Spring Data includes repository support for LDAP.

For complete details of Spring Data LDAP, see the reference documentation.

You can also inject an auto-configured LdapTemplate instance as you would with any other Spring Bean, as shown in the following example:

Java
Kotlin

import java.util.List;

import org.springframework.ldap.core.LdapTemplate;
import org.springframework.stereotype.Component;

@Component
public class MyBean {

	private final LdapTemplate template;

	public MyBean(LdapTemplate template) {
		this.template = template;
	}

	// ...

	public List<User> someMethod() {
		return this.template.findAll(User.class);
	}

}

import org.springframework.ldap.core.LdapTemplate
import org.springframework.stereotype.Component

@Component
class MyBean(private val template: LdapTemplate) {

	// ...

	fun someMethod(): List<User> {
		return template.findAll(User::class.java)
	}

}

Embedded In-memory LDAP Server

For testing purposes, Spring Boot supports auto-configuration of an in-memory LDAP server from UnboundID. To configure the server, add a dependency to com.unboundid:unboundid-ldapsdk and declare a spring.ldap.embedded.base-dn property, as follows:

Properties
YAML

spring.ldap.embedded.base-dn=dc=spring,dc=io

spring:
  ldap:
    embedded:
      base-dn: "dc=spring,dc=io"

It is possible to define multiple base-dn values, however, since distinguished names usually contain commas, they must be defined using the correct notation.

In yaml files, you can use the yaml list notation. In properties files, you must include the index as part of the property name:

Properties
YAML

spring.ldap.embedded.base-dn[0]=dc=spring,dc=io
spring.ldap.embedded.base-dn[1]=dc=vmware,dc=com

spring.ldap.embedded.base-dn:
- "dc=spring,dc=io"
- "dc=vmware,dc=com"

By default, the server starts on a random port and triggers the regular LDAP support. There is no need to specify a spring.ldap.urls property.

If there is a schema.ldif file on your classpath, it is used to initialize the server. If you want to load the initialization script from a different resource, you can also use the spring.ldap.embedded.ldif property.

By default, a standard schema is used to validate LDIF files. You can turn off validation altogether by setting the spring.ldap.embedded.validation.enabled property. If you have custom attributes, you can use spring.ldap.embedded.validation.schema to define your custom attribute types or object classes.