Spring Data Couchbase

The primary goal of the Spring Data project is to make it easier to build Spring-powered applications that use new data access technologies such as non-relational databases, map-reduce frameworks, and cloud based data services.

The Spring Data Couchbase project aims to provide a familiar and consistent Spring-based programming model for Couchbase Server as a document database and cache while retaining store-specific features and capabilities. Key functional areas of Spring Data Couchbase are a POJO centric model for interacting with a Couchbase Server Bucket and easily writing a repository style data access layer.

Getting Help

For a comprehensive treatment of all the Spring Data Couchbase features, please refer to:

• the User Guide
• the JavaDocs have extensive comments in them as well.
• for more detailed questions, use the forum.

If you are new to Spring as well as to Spring Data, look for information about Spring projects.

Quick Start

Maven configuration

Add the Maven dependency:

<dependency>
  <groupId>org.springframework.data</groupId>
  <artifactId>spring-data-couchbase</artifactId>
  <version>1.2.2.RELEASE</version>
</dependency>

If you'd rather like the latest snapshots of the upcoming major version, use our Maven snapshot repository and declare the appropriate dependency version.

<dependency>
  <groupId>org.springframework.data</groupId>
  <artifactId>spring-data-couchbase</artifactId>
  <version>1.3.0.BUILD-SNAPSHOT</version>
</dependency>

<repository>
  <id>spring-libs-snapshot</id>
  <name>Spring Snapshot Repository</name>
  <url>http://repo.spring.io/libs-snapshot</url>
</repository>

CouchbaseTemplate

CouchbaseTemplate is the central support class for Couchbase database operations. It provides:

• Basic POJO mapping support to and from JSON (by default through Jackson)
• Convenience methods to interact with the store (insert object, update objects) and Couchbase specific ones
• Exception translation into Spring's technology agnostic DAO exception hierarchy.

Spring Data Repositories

To simplify the creation of data repositories Spring Data COUCHBASE provides a generic repository programming model. It will automatically create a repository proxy for you that adds implementations of finder methods you specify on an interface.

To create a repository on top of a User entity, all you need to write is:

public interface UserRepository extends CrudRepository<User, String> {

    /**
     * Additional custom finder method.
     */
	List<User> findByLastname(Query query);

}

Once you get a reference to that repository bean, you'll find a lot of methods that make it very easy o work with this entity. In addition to the ones provided through the CrudRepository, you can add your own methods as well.

In general, every finder method that does not depend on a single key (like findById) needs a backing View on the server side. In the example above, it assumes you have a view named findByLastname in the user design document. You can customize the view and design document name through the @View annotation. Also make sure you publish them into production before accessing it.

This is an example view for the findByLastname method:

function (doc, meta) {
  if(doc._class == "com.example.entity.User" && doc.firstname) {
    emit(doc.firstname, null);
  }
}

You can pass in custom runtime parameters through the Query param.

To make the findAll() and count view work, it needs to look like this (and do not forget the _count reduce function):

function (doc, meta) {
  if(doc._class == "com.example.entity.User") {
    emit(null, null);
  }
}

The queries issued on execution will be derived from the method name. Extending CrudRepository causes CRUD methods being pulled into the interface so that you can easily save and find single entities and collections of them.

You can have Spring automatically create a proxy for the interface by using the following JavaConfig:

@Configuration
@EnableCouchbaseRepositories
public class Config extends AbstractCouchbaseConfiguration {

	@Override
	protected List<String> bootstrapHosts() {
		return Arrays.asList("host1", "host2");
	}

	@Override
	protected String getBucketName() {
		return "default";
	}

	@Override
	protected String getBucketPassword() {
		return "";
	}
}

This sets up a connection to a Couchbase cluster and enables the detection of Spring Data repositories (through `@EnableCouchbaseRepositories). The same configuration would look like this in XML:

<couchbase:couchbase id="cb-first" bucket="default" password="" host="localhost" />
<couchbase:template id="cb-template-first"  client-ref="cb-first" />
<couchbase:repositories couchbase-template-ref="cb-template-first" />

This will find the repository interface and register a proxy object in the container. You can use it as shown below:

@Service
public class MyService {

	private final UserRepository userRepository;

    @Autowired
	public MyService(UserRepository userRepository) {
		this.userRepository = userRepository;
	}

	public void doWork() {
		userRepository.deleteAll();

		User user = new User();
		user.setLastname("Jackson");

		user = userRepository.save(user);

		Query query = new Query();
		query.setKey(ComplexKey.of("Jackson"));
		List<User> allUsers = userRepository.findByLastname(query);

	}
}

Contributing to Spring Data

Here are some ways for you to get involved in the community:

• Get involved with the Spring community on the Spring Community Forums. Please help out on the forum by responding to questions and joining the debate.
• Create JIRA tickets for bugs and new features and comment and vote on the ones that you are interested in.
• Github is for social coding: if you want to write code, we encourage contributions through pull requests from forks of this repository. If you want to contribute code this way, please reference a JIRA ticket as well covering the specific issue you are addressing.
• Watch for upcoming articles on Spring by subscribing to springframework.org

Before we accept a non-trivial patch or pull request we will need you to sign the contributor's agreement. Signing the contributor's agreement does not grant anyone commit rights to the main repository, but it does mean that we can accept your contributions, and you will get an author credit if we do. Active contributors might be asked to join the core team, and given the ability to merge pull requests.