Azure Spring Data Cosmos client library for Java

Azure Spring Data Cosmos provides Spring Data support for Azure Cosmos DB using the SQL API, based on Spring Data framework. Azure Cosmos DB is a globally distributed database service, which allows developers to work with data using a variety of standard APIs, such as SQL, MongoDB, Cassandra, Graph, and Table.

Spring data version support

This project supports both spring-data-commons 2.2.x and spring-data-commons 2.3.x versions. Maven users can inherit from the spring-boot-starter-parent project to obtain a dependency management section to let Spring manage the versions for dependencies.

<!-- Inherit defaults from Spring Boot -->
<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>${spring.boot.version}</version>
</parent>

With that setup, you can also override individual dependencies by overriding a property in your own project. For instance, to upgrade to another Spring Data release train you’d add the following to your pom.xml.

<properties>
    <spring-data-releasetrain.version>${spring.data.version}</spring-data-releasetrain.version>
</properties>

If you don’t want to use the spring-boot-starter-parent, you can still keep the benefit of the dependency management by using a scope=import dependency:

<dependencyManagement>
     <dependencies>
        <dependency>
            <!-- Import dependency management from Spring Boot -->
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-dependencies</artifactId>
            <version>${spring.boot.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

That setup does not allow you to override individual dependencies using a property as explained above. To achieve the same result, you’d need to add an entry in the dependencyManagement of your project before the spring-boot-dependencies entry. For instance, to upgrade to another Spring Data release train you’d add the following to your pom.xml.

<dependencyManagement>
    <dependencies>
        <!-- Override Spring Data release train provided by Spring Boot -->
        <dependency>
            <groupId>org.springframework.data</groupId>
            <artifactId>spring-data-releasetrain</artifactId>
            <version>${spring.data.version}</version>
            <scope>import</scope>
            <type>pom</type>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-dependencies</artifactId>
            <version>${spring.boot.version}</version>
            <type>pom</type>
            <scope>import</scope>
        </dependency>
    </dependencies>
</dependencyManagement>

Note

Replace the ${spring.boot.version} and ${spring.data.version} with the versions of Spring Boot and Spring Data you want to use in your project.

Getting started

Include the package

If you are using Maven, add the following dependency.

<dependency>
    <groupId>com.azure</groupId>
    <artifactId>azure-spring-data-cosmos</artifactId>
    <version>3.9.0</version>
</dependency>

Prerequisites

  • Java Development Kit (JDK), version 8 or later.
  • An active Azure account. If you don't have one, you can sign up for a free account. Alternatively, you can use the Azure Cosmos DB Emulator for development and testing. As emulator https certificate is self-signed, you need to import its certificate to java trusted cert store, explained here
  • (Optional) SLF4J is a logging facade.
  • (Optional) SLF4J binding is used to associate a specific logging framework with SLF4J.
  • (Optional) Maven

SLF4J is only needed if you plan to use logging, please also download an SLF4J binding which will link the SLF4J API with the logging implementation of your choice. See the SLF4J user manual for more information.

Setup Configuration Class

In order to set up configuration class, you'll need to extend AbstractCosmosConfiguration

Azure-spring-data-cosmos also supports Response Diagnostics String and Query Metrics. Set queryMetricsEnabled flag to true in application.properties to enable query metrics. In addition to setting the flag, implement ResponseDiagnosticsProcessor to log diagnostics information.

@Configuration
@EnableCosmosRepositories
public class AppConfiguration extends AbstractCosmosConfiguration {

    private static final Logger LOGGER = LoggerFactory.getLogger(AppConfiguration.class);

    @Value("${azure.cosmos.uri}")
    private String uri;

    @Value("${azure.cosmos.key}")
    private String key;

    @Value("${azure.cosmos.secondaryKey}")
    private String secondaryKey;

    @Value("${azure.cosmos.database}")
    private String dbName;

    @Value("${azure.cosmos.queryMetricsEnabled}")
    private boolean queryMetricsEnabled;

    private AzureKeyCredential azureKeyCredential;

    @Bean
    public CosmosClientBuilder getCosmosClientBuilder() {
        this.azureKeyCredential = new AzureKeyCredential(key);
        DirectConnectionConfig directConnectionConfig = new DirectConnectionConfig();
        GatewayConnectionConfig gatewayConnectionConfig = new GatewayConnectionConfig();
        return new CosmosClientBuilder()
            .endpoint(uri)
            .credential(azureKeyCredential)
            .directMode(directConnectionConfig, gatewayConnectionConfig);
    }

    @Override
    public CosmosConfig cosmosConfig() {
        return CosmosConfig.builder()
                           .enableQueryMetrics(queryMetricsEnabled)
                           .responseDiagnosticsProcessor(new ResponseDiagnosticsProcessorImplementation())
                           .build();
    }

    public void switchToSecondaryKey() {
        this.azureKeyCredential.update(secondaryKey);
    }

    @Override
    protected String getDatabaseName() {
        return "testdb";
    }

    private static class ResponseDiagnosticsProcessorImplementation implements ResponseDiagnosticsProcessor {

        @Override
        public void processResponseDiagnostics(@Nullable ResponseDiagnostics responseDiagnostics) {
            LOGGER.info("Response Diagnostics {}", responseDiagnostics);
        }
    }

}

Customizing Configuration

You can customize DirectConnectionConfig or GatewayConnectionConfig or both and provide them to CosmosClientBuilder bean to customize CosmosAsyncClient

@Bean
public CosmosClientBuilder getCosmosClientBuilder() {

    DirectConnectionConfig directConnectionConfig = new DirectConnectionConfig();
    GatewayConnectionConfig gatewayConnectionConfig = new GatewayConnectionConfig();
    return new CosmosClientBuilder()
        .endpoint(uri)
        .directMode(directConnectionConfig, gatewayConnectionConfig);
}

@Override
public CosmosConfig cosmosConfig() {
    return CosmosConfig.builder()
                       .enableQueryMetrics(queryMetricsEnabled)
                       .responseDiagnosticsProcessor(new ResponseDiagnosticsProcessorImplementation())
                       .build();
}

By default, @EnableCosmosRepositories will scan the current package for any interfaces that extend one of Spring Data's repository interfaces. Use it to annotate your Configuration class to scan a different root package by @EnableCosmosRepositories(basePackageClass=UserRepository.class) if your project layout has multiple projects.

Define an entity

Define a simple entity as item in Azure Cosmos DB.

You can define entities by adding the @Container annotation and specifying properties related to the container, such as the container name, request units (RUs), time to live, and auto-create container.

Containers will be created automatically unless you don't want them to. Set autoCreateContainer to false in @Container annotation to disable auto creation of containers.

Note

By default request units assigned to newly created containers is 400. Specify different ru value to customize request units for the container created by the SDK (minimum RU value is 400).

@Container(containerName = "myContainer", ru = "400")
public class User {
    private String id;
    private String firstName;


    @PartitionKey
    private String lastName;

    public User() {
        // If you do not want to create a default constructor,
        // use annotation @JsonCreator and @JsonProperty in the full args constructor
    }

    public User(String id, String firstName, String lastName) {
        this.id = id;
        this.firstName = firstName;
        this.lastName = lastName;
    }

    @Override
    public String toString() {
        return String.format("User: %s %s, %s", firstName, lastName, id);
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getFirstName() {
        return firstName;
    }

    public void setFirstName(String firstName) {
        this.firstName = firstName;
    }

    public String getLastName() {
        return lastName;
    }

    public void setLastName(String lastName) {
        this.lastName = lastName;
    }
}

The id field will be used as Item ID in Azure Cosmos DB. If you want to use another field like firstName as item id, just annotate that field with @Id annotation.

The annotation @Container(containerName="myContainer") specifies container name in Azure Cosmos DB.

The annotation @PartitionKey on lastName field specifies this field as partition key in Azure Cosmos DB.

Creating Containers with autoscale throughput

The annotation autoScale field specifies container to be created with autoscale throughput if set to true. Default is false, which means containers are created with manual throughput.

Read more about autoscale throughput here

@Container(containerName = "myContainer", autoScale = true, ru = "4000")
public class UserSample {
    @Id
    private String emailAddress;

}

Nested Partition Key support

Spring Data Cosmos SDK supports nested partition key. To add nested partition key, use partitionKeyPath field in @Container annotation.

partitionKeyPath should only be used to support nested partition key path. For general partition key support, use the @PartitionKey annotation.

By default @PartitionKey annotation will take precedence, unless not specified.

The following example shows how to properly use Nested Partition key feature.

@Container(containerName = "nested-partition-key", partitionKeyPath = "/nestedEntitySample/nestedPartitionKey")
public class NestedPartitionKeyEntitySample {

    private NestedEntitySample nestedEntitySample;
}
public class NestedEntitySample {
    private String nestedPartitionKey;
}

Create repositories

Extends CosmosRepository interface, which provides Spring Data repository support.

@Repository
public interface UserRepository extends CosmosRepository<User, String> {
    Iterable<User> findByFirstName(String firstName);
    long countByFirstName(String firstName);
    User findOne(String id, String lastName);
}
  • findByFirstName method is custom query method, it will find items per firstName.

QueryAnnotation : Using annotated queries in repositories

Azure spring data cosmos supports specifying annotated queries in the repositories using @Query.

Here are some examples for annotated queries in synchronous CosmosRepository:

public interface AnnotatedQueriesUserRepositoryCodeSnippet extends CosmosRepository<User, String> {
    @Query("select * from c where c.firstName = @firstName and c.lastName = @lastName")
    List<User> getUsersByFirstNameAndLastName(@Param("firstName") String firstName, @Param("lastName") String lastName);

    @Query("select * from c offset @offset limit @limit")
    List<User> getUsersWithOffsetLimit(@Param("offset") int offset, @Param("limit") int limit);

    @Query("select value count(1) from c where c.firstName = @firstName")
    long getNumberOfUsersWithFirstName(@Param("firstName") String firstName);
}

Here are some examples for annotated queries in ReactiveCosmosRepository.

public interface AnnotatedQueriesUserReactiveRepositoryCodeSnippet extends ReactiveCosmosRepository<User, String> {
    @Query("select * from c where c.firstName = @firstName and c.lastName = @lastName")
    Flux<User> getUsersByTitleAndValue(@Param("firstName") int firstName, @Param("lastName") String lastName);

    @Query("select * from c offset @offset limit @limit")
    Flux<User> getUsersWithOffsetLimit(@Param("offset") int offset, @Param("limit") int limit);

    @Query("select count(c.id) as num_ids, c.lastName from c group by c.lastName")
    Flux<ObjectNode> getCoursesGroupByDepartment();

    @Query("select value count(1) from c where c.lastName = @lastName")
    Mono<Long> getNumberOfUsersWithLastName(@Param("lastName") String lastName);
}

The queries that are specified in the annotation are same as the Cosmos queries. Please refer to the following articles for more information on SQL queries in Cosmos:

Create an Application class

Here create an application class with all the components.

@SpringBootApplication
public class SampleApplication implements CommandLineRunner {

    @Autowired
    private UserRepository repository;

    @Autowired
    private ApplicationContext applicationContext;

    public static void main(String[] args) {
        SpringApplication.run(SampleApplication.class, args);
    }

    public void run(String... var1) {

        final User testUser = new User("testId", "testFirstName", "testLastName");

        repository.deleteAll();
        repository.save(testUser);

        // to find by Id, please specify partition key value if collection is partitioned
        final User result = repository.findOne(testUser.getId(), testUser.getLastName());

        //  Switch to secondary key
        UserRepositoryConfiguration bean =
            applicationContext.getBean(UserRepositoryConfiguration.class);
        bean.switchToSecondaryKey();

        //  Now repository will use secondary key
        repository.save(testUser);

    }
}

Autowire the UserRepository interface, to perform operations like save, delete, find, and so on.

Spring Data Azure Cosmos DB uses the CosmosTemplate and ReactiveCosmosTemplate to execute the queries behind find, save methods. You can use the template yourself for more complex queries.

Key concepts

CrudRepository and ReactiveCrudRepository

Azure Spring Data Cosmos supports ReactiveCrudRepository and CrudRepository which provides basic CRUD functionality:

  • save
  • findAll
  • findOne by ID
  • deleteAll
  • delete by ID
  • delete entity

Spring Data Annotations

There are 2 ways to map a field in domain class to id field of Azure Cosmos DB Item: - annotate a field in domain class with @Id, this field will be mapped to Item id in Cosmos DB. - set name of this field to id, this field will be mapped to Item id in Azure Cosmos DB.

Supports auto generation of string type UUIDs using the @GeneratedValue annotation. The ID field of an entity with a string type ID can be annotated with @GeneratedValue to automatically generate a random UUID prior to insertion.

public class GeneratedIdEntity {

    @Id
    @GeneratedValue
    private String id;

}
  • SpEL Expression and Custom Container Name.
    • By default, container name will be class name of user domain class. To customize it, add the @Container(containerName="myCustomContainerName") annotation to the domain class. The container field also supports SpEL expressions (eg. container = "${dynamic.container.name}" or container = "#{@someBean.getContainerName()}") in order to provide container names programmatically/via configuration properties.
    • In order for SpEL expressions to work properly, you need to add @DependsOn("expressionResolver") on top of Spring Application class.
@SpringBootApplication
@DependsOn("expressionResolver")
public class SampleApplication {

}
  • Custom IndexingPolicy By default, IndexingPolicy will be set by Azure service. To customize it add annotation @CosmosIndexingPolicy to domain class. This annotation has 4 attributes to customize, see following:
// Indicate if indexing policy use automatic or not
// Default value is true
boolean automatic() default Constants.DEFAULT_INDEXING_POLICY_AUTOMATIC;

// Indexing policy mode, option Consistent.
IndexingMode mode() default IndexingMode.CONSISTENT;

// Included paths for indexing
String[] includePaths() default {};

// Excluded paths for indexing
String[] excludePaths() default {};

Azure Cosmos DB Partition

Azure-spring-data-cosmos supports Azure Cosmos DB partition.

To specify a field of domain class to be partition key field, just annotate it with @PartitionKey.

When you perform CRUD operation, specify your partition value.

For more sample on partition CRUD, please refer test here

Optimistic Locking

Azure-spring-data-cosmos supports Optimistic Locking for specific containers, which means upserts/deletes by item will fail with an exception in case the item is modified by another process in the meanwhile.

To enable Optimistic Locking for a container, just create a string _etag field and mark it with the @Version annotation. See the following:

@Container(containerName = "myContainer")
public class MyItem {
    String id;
    String data;
    @Version
    String _etag;
}

Spring Data custom query, pageable and sorting

Azure-spring-data-cosmos supports spring data custom queries, for example, a find operation such as findByAFieldAndBField

Supports Spring Data Pageable, Slice and Sort. - Based on available RUs on the database account, cosmosDB can return items less than or equal to the requested size. - Due to this variable number of returned items in every iteration, user should not rely on the totalPageSize, and instead iterating over pageable should be done in this way.

private List<T> findAllWithPageSize(int pageSize) {

    final CosmosPageRequest pageRequest = new CosmosPageRequest(0, pageSize, null);
    Page<T> page = repository.findAll(pageRequest);
    List<T> pageContent = page.getContent();
    while (page.hasNext()) {
        Pageable nextPageable = page.nextPageable();
        page = repository.findAll(nextPageable);
        pageContent = page.getContent();
    }
    return pageContent;
}
public interface SliceQueriesUserRepository extends CosmosRepository<User, String> {
    @Query("select * from c where c.lastName = @lastName")
    Slice<User> getUsersByLastName(@Param("lastName") String lastName, Pageable pageable);
}
private List<User> getUsersByLastName(String lastName, int pageSize) {

    final CosmosPageRequest pageRequest = new CosmosPageRequest(0, pageSize, null);
    Slice<User> slice = repository.getUsersByLastName(lastName, pageRequest);
    List<User> content = slice.getContent();
    while (slice.hasNext()) {
        Pageable nextPageable = slice.nextPageable();
        slice = repository.getUsersByLastName(lastName, nextPageable);
        content.addAll(slice.getContent());
    }
    return content;
}

Spring Boot Starter Data Rest

Azure-spring-data-cosmos supports spring-boot-starter-data-rest.

  • Supports List and nested type in domain class.
  • Configurable ObjectMapper bean with unique name cosmosObjectMapper, only configure customized ObjectMapper if you really need to. For example:
@Bean(name = "cosmosObjectMapper")
public ObjectMapper objectMapper() {
    return new ObjectMapper(); // Do configuration to the ObjectMapper if required
}

Auditing

Azure-spring-data-cosmos supports auditing fields on database entities using standard spring-data annotations.

This feature can be enabled by adding @EnableCosmosAuditing annotation to your application configuration.

Entities can annotate fields using @CreatedBy, @CreatedDate, @LastModifiedBy and @LastModifiedDate. These fields will be updated automatically.

@Container(containerName = "myContainer")
public class AuditableUser {
    private String id;
    private String firstName;
    @CreatedBy
    private String createdBy;
    @CreatedDate
    private OffsetDateTime createdDate;
    @LastModifiedBy
    private String lastModifiedBy;
    @LastModifiedDate
    private OffsetDateTime lastModifiedByDate;
}

Multi-database configuration

Azure-spring-data-cosmos supports multi-database configuration, including "multiple database accounts" and "single account, with multiple databases".

Multi-database accounts

The example uses the application.properties file:

# primary account cosmos config
azure.cosmos.primary.uri=your-primary-cosmosDb-uri
azure.cosmos.primary.key=your-primary-cosmosDb-key
azure.cosmos.primary.secondaryKey=your-primary-cosmosDb-secondary-key
azure.cosmos.primary.database=your-primary-cosmosDb-dbName
azure.cosmos.primary.populateQueryMetrics=if-populate-query-metrics

# secondary account cosmos config
azure.cosmos.secondary.uri=your-secondary-cosmosDb-uri
azure.cosmos.secondary.key=your-secondary-cosmosDb-key
azure.cosmos.secondary.secondaryKey=your-secondary-cosmosDb-secondary-key
azure.cosmos.secondary.database=your-secondary-cosmosDb-dbName
azure.cosmos.secondary.populateQueryMetrics=if-populate-query-metrics

The Entity and Repository definition is similar as above. You can put different database entities into different packages.

The @EnableReactiveCosmosRepositories or @EnableCosmosRepositories support user-define the cosmos template, use reactiveCosmosTemplateRef or cosmosTemplateRef to config the name of the ReactiveCosmosTemplate or CosmosTemplate bean to be used with the repositories detected.

If you have multiple cosmos database accounts, you can define multiple CosmosAsyncClient. If the single cosmos account has multiple databases, you can use the same CosmosAsyncClient to initialize the cosmos template.

@Configuration
@EnableReactiveCosmosRepositories(basePackages = "com.azure.spring.sample.cosmos.multi.database.multiple.account.repository",
    reactiveCosmosTemplateRef = "primaryDatabaseTemplate")
public class PrimaryDatasourceConfiguration extends AbstractCosmosConfiguration{

    private static final String PRIMARY_DATABASE = "primary_database";

    @Bean
    @ConfigurationProperties(prefix = "azure.cosmos.primary")
    public CosmosProperties primary() {
        return new CosmosProperties();
    }

    @Bean
    public CosmosClientBuilder primaryClientBuilder(@Qualifier("primary") CosmosProperties primaryProperties) {
        return new CosmosClientBuilder()
            .key(primaryProperties.getKey())
            .endpoint(primaryProperties.getUri());
    }

    @Bean
    public ReactiveCosmosTemplate primaryDatabaseTemplate(CosmosAsyncClient cosmosAsyncClient,
                                                          CosmosConfig cosmosConfig,
                                                          MappingCosmosConverter mappingCosmosConverter) {
        return new ReactiveCosmosTemplate(cosmosAsyncClient, PRIMARY_DATABASE, cosmosConfig, mappingCosmosConverter);
    }

    @Override
    protected String getDatabaseName() {
        return PRIMARY_DATABASE;
    }
}
@Configuration
@EnableCosmosRepositories(cosmosTemplateRef  = "secondaryDatabaseTemplate")
public class SecondaryDatasourceConfiguration {

    private static final Logger LOGGER = LoggerFactory.getLogger(SecondaryDatasourceConfiguration.class);
    public static final String SECONDARY_DATABASE = "secondary_database";

    @Bean
    @ConfigurationProperties(prefix = "azure.cosmos.secondary")
    public CosmosProperties secondary() {
        return new CosmosProperties();
    }

    @Bean("secondaryCosmosClient")
    public CosmosAsyncClient getCosmosAsyncClient(@Qualifier("secondary") CosmosProperties secondaryProperties) {
        return CosmosFactory.createCosmosAsyncClient(new CosmosClientBuilder()
            .key(secondaryProperties.getKey())
            .endpoint(secondaryProperties.getUri()));
    }

    @Bean("secondaryCosmosConfig")
    public CosmosConfig getCosmosConfig() {
        return CosmosConfig.builder()
            .enableQueryMetrics(true)
            .responseDiagnosticsProcessor(new ResponseDiagnosticsProcessorImplementation())
            .build();
    }

    @Bean
    public CosmosTemplate secondaryDatabaseTemplate(@Qualifier("secondaryCosmosClient") CosmosAsyncClient client,
                                                    @Qualifier("secondaryCosmosConfig") CosmosConfig cosmosConfig,
                                                    MappingCosmosConverter mappingCosmosConverter) {
        return new CosmosTemplate(client, SECONDARY_DATABASE, cosmosConfig, mappingCosmosConverter);
    }

    private static class ResponseDiagnosticsProcessorImplementation implements ResponseDiagnosticsProcessor {

        @Override
        public void processResponseDiagnostics(@Nullable ResponseDiagnostics responseDiagnostics) {
            LOGGER.info("Response Diagnostics {}", responseDiagnostics);
        }
    }
}

In the above example, we have two Cosmos accounts. You can create the CosmosAsyncClient like this:

@Bean("secondaryCosmosClient")
public CosmosAsyncClient getCosmosAsyncClient(@Qualifier("secondary") CosmosProperties secondaryProperties) {
    return CosmosFactory.createCosmosAsyncClient(new CosmosClientBuilder()
        .key(secondaryProperties.getKey())
        .endpoint(secondaryProperties.getUri()));
}

@Bean("secondaryCosmosConfig")
public CosmosConfig getCosmosConfig() {
    return CosmosConfig.builder()
        .enableQueryMetrics(true)
        .responseDiagnosticsProcessor(new ResponseDiagnosticsProcessorImplementation())
        .build();
}

If you want to define queryMetricsEnabled or ResponseDiagnosticsProcessor, you can create the CosmosConfig for your Cosmos template.

@Bean("secondaryCosmosConfig")
public CosmosConfig getCosmosConfig() {
    return CosmosConfig.builder()
        .enableQueryMetrics(true)
        .responseDiagnosticsProcessor(new ResponseDiagnosticsProcessorImplementation())
        .build();
}

Create an Application class:

@SpringBootApplication
public class MultiDatabaseApplication implements CommandLineRunner {

    @Autowired
    private CosmosUserRepository cosmosUserRepository;

    @Autowired
    private MysqlUserRepository mysqlUserRepository;

    @Autowired
    @Qualifier("secondaryDatabaseTemplate")
    private CosmosTemplate secondaryDatabaseTemplate;

    @Autowired
    @Qualifier("primaryDatabaseTemplate")
    private ReactiveCosmosTemplate primaryDatabaseTemplate;

    private final CosmosUser cosmosUser = new CosmosUser("1024", "1024@geek.com", "1k", "Mars");
    private static CosmosEntityInformation<CosmosUser, String> userInfo = new CosmosEntityInformation<>(CosmosUser.class);

    public static void main(String[] args) {
        SpringApplication.run(MultiDatabaseApplication.class, args);
    }

    public void run(String... var1) throws Exception {

        CosmosUser cosmosUserGet = primaryDatabaseTemplate.findById(cosmosUser.getId(), cosmosUser.getClass()).block();
        // Same to this.cosmosUserRepository.findById(cosmosUser.getId()).block();
        MysqlUser mysqlUser = new MysqlUser(cosmosUserGet.getId(), cosmosUserGet.getEmail(), cosmosUserGet.getName(), cosmosUserGet.getAddress());
        mysqlUserRepository.save(mysqlUser);
        mysqlUserRepository.findAll().forEach(System.out::println);
        CosmosUser secondaryCosmosUserGet = secondaryDatabaseTemplate.findById(CosmosUser.class.getSimpleName(), cosmosUser.getId(), CosmosUser.class);
        System.out.println(secondaryCosmosUserGet);
    }


    @PostConstruct
    public void setup() {
        primaryDatabaseTemplate.createContainerIfNotExists(userInfo).block();
        primaryDatabaseTemplate.insert(CosmosUser.class.getSimpleName(), cosmosUser, new PartitionKey(cosmosUser.getName())).block();
        // Same to this.cosmosUserRepository.save(user).block();
        secondaryDatabaseTemplate.createContainerIfNotExists(userInfo);
        secondaryDatabaseTemplate.insert(CosmosUser.class.getSimpleName(), cosmosUser, new PartitionKey(cosmosUser.getName()));
   }

    @PreDestroy
    public void cleanup() {
        primaryDatabaseTemplate.deleteAll(CosmosUser.class.getSimpleName(), CosmosUser.class).block();
        // Same to this.cosmosUserRepository.deleteAll().block();
        secondaryDatabaseTemplate.deleteAll(CosmosUser.class.getSimpleName() , CosmosUser.class);
        mysqlUserRepository.deleteAll();
    }
}

Single account with Multi-database

The example uses the application.properties file:

azure.cosmos.uri=your-cosmosDb-uri
azure.cosmos.key=your-cosmosDb-key
azure.cosmos.secondary-key=your-cosmosDb-secondary-key
azure.cosmos.database=your-cosmosDb-dbName
azure.cosmos.populate-query-metrics=if-populate-query-metrics

The Entity and Repository definition is similar as above. You can put different database entities into different packages.

You can use EnableReactiveCosmosRepositories with different reactiveCosmosTemplateRef to define multiple databases in single cosmos account.

@Configuration
public class DatasourceConfiguration {

    private static final String DATABASE1 = "database1";
    private static final String DATABASE2 = "database2";

    @Bean
    public CosmosProperties cosmosProperties() {
        return new CosmosProperties();
    }

    @Bean
    public CosmosClientBuilder primaryClientBuilder(CosmosProperties cosmosProperties) {
        return new CosmosClientBuilder()
            .key(cosmosProperties.getKey())
            .endpoint(cosmosProperties.getUri());
    }

    @EnableReactiveCosmosRepositories(basePackages = "com.azure.spring.sample.cosmos.multi.database.repository1",
        reactiveCosmosTemplateRef = "database1Template")
    public class Database1Configuration extends AbstractCosmosConfiguration {

        @Bean
        public ReactiveCosmosTemplate database1Template(CosmosAsyncClient cosmosAsyncClient,
                                                              CosmosConfig cosmosConfig,
                                                              MappingCosmosConverter mappingCosmosConverter) {
            return new ReactiveCosmosTemplate(cosmosAsyncClient, DATABASE1, cosmosConfig, mappingCosmosConverter);
        }

        @Override
        protected String getDatabaseName() {
            return DATABASE1;
        }
    }

    @EnableReactiveCosmosRepositories(basePackages = "com.azure.spring.sample.cosmos.multi.database.repository2",
        reactiveCosmosTemplateRef = "database2Template")
    public class Database2Configuration {

        @Bean
        public ReactiveCosmosTemplate database2Template(CosmosAsyncClient cosmosAsyncClient,
                                                              CosmosConfig cosmosConfig,
                                                              MappingCosmosConverter mappingCosmosConverter) {
            return new ReactiveCosmosTemplate(cosmosAsyncClient, DATABASE2, cosmosConfig, mappingCosmosConverter);
        }

    }
}

Create an Application class:

@SpringBootApplication
public class MultiDatabaseApplication implements CommandLineRunner {

    @Autowired
    private User1Repository user1Repository;

    @Autowired
    @Qualifier("database1Template")
    private ReactiveCosmosTemplate database1Template;

    @Autowired
    @Qualifier("database2Template")
    private ReactiveCosmosTemplate database2Template;

    private final User1 user1 = new User1("1024", "1024@geek.com", "1k", "Mars");
    private static CosmosEntityInformation<User1, String> user1Info = new CosmosEntityInformation<>(User1.class);

    private final User2 user2 = new User2("2048", "2048@geek.com", "2k", "Mars");
    private static CosmosEntityInformation<User2, String> user2Info = new CosmosEntityInformation<>(User2.class);


    public static void main(String[] args) {
        SpringApplication.run(MultiDatabaseApplication.class, args);
    }

    public void run(String... var1) throws Exception {

        User1 database1UserGet = database1Template.findById(User1.class.getSimpleName(), user1.getId(), User1.class).block();
        // Same to userRepository1.findById(user.getId()).block()
        System.out.println(database1UserGet);
        User2 database2UserGet = database2Template.findById(User2.class.getSimpleName(), user2.getId(), User2.class).block();
        System.out.println(database2UserGet);
    }

    @PostConstruct
    public void setup() {
        database1Template.createContainerIfNotExists(user1Info).block();
        database1Template.insert(User1.class.getSimpleName(), user1, new PartitionKey(user1.getName())).block();
        // Same to this.userRepository1.save(user).block();
        database2Template.createContainerIfNotExists(user2Info).block();
        database2Template.insert(User2.class.getSimpleName(), user2, new PartitionKey(user2.getName())).block();
    }

    @PreDestroy
    public void cleanup() {
        database1Template.deleteAll(User1.class.getSimpleName(), User1.class).block();
        // Same to this.userRepository1.deleteAll().block();
        database2Template.deleteAll(User2.class.getSimpleName(), User2.class).block();
    }
}

Beta version package

Beta version built from master branch are available, you can refer to the instruction to use beta version packages.

Troubleshooting

General

If you encounter any bug, please file an issue here.

To suggest a new feature or changes that could be made, file an issue the same way you would for a bug.

Enable Client Logging

Azure-spring-data-cosmos uses SLF4j as the logging facade that supports logging into popular logging frameworks such as log4j and logback. For example, if you want to use spring logback as logging framework, add the following xml to resources folder.

<configuration>
  <include resource="/org/springframework/boot/logging/logback/base.xml"/>
  <appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
    <encoder>
      <pattern>%d{HH:mm:ss.SSS} [%thread] %-5level %logger{36} - %msg%n
      </pattern>
    </encoder>
  </appender>
  <root level="info">
    <appender-ref ref="STDOUT"/>
  </root>
  <logger name="com.azure.cosmos" level="error"/>
  <logger name="org.springframework" level="error"/>
  <logger name="io.netty" level="error"/>
  <!-- This will enable query logging, to include query parameter logging, set this logger to TRACE -->  
  <logger name="com.azure.cosmos.implementation.SqlQuerySpecLogger" level="DEBUG"/>  
</configuration>

Examples

Please refer to sample project here.

Multi-database accounts

Please refer to Multi-database sample project.

Single account with Multi-database

Please refer to Single account with Multi-database sample project.

Next steps

Contributing

This project welcomes contributions and suggestions. Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution.

When you submit a pull request, a CLA-bot will automatically determine whether you need to provide a CLA and decorate the PR appropriately (e.g., label, comment). Simply follow the instructions provided by the bot. You will only need to do this once across all repos using our CLA.

This project has adopted the Microsoft Open Source Code of Conduct. For more information see the Code of Conduct FAQ or contact opencode@microsoft.com with any additional questions or comments.

Impressions