Spring Boot - MySQL and DynamoDB together

Expected Behavior

Normal startup. MySQL repos work with MySQL entities (and they actually do), DynamoDB repos work with DynamoDB entities.

Actual Behavior

Spring Boot app does not start due to an error with @DynamoDBTable entity. It seems autoconfiguration does not work for DynamoDB. Should I renounce to automatic JPA configuration, maybe?

Steps to Reproduce the Problem

1. Use “spring-boot-starter-data-jpa” within dependecies
2. Create some repos for MySQL entities
3. Create a DynamoDBTable entity (in the same “model” folder of MySQL entities (see ‘A’)
4. Create DynamoDBConfig class (see ‘B’)
5. Create DynamoDB Crude Repository (see ‘C’)
6. Start the app

A:

package com.somotic.scm.model;

import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBAttribute;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBHashKey;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBRangeKey;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBTable;

import javax.persistence.Id;
import java.io.Serializable;
import java.util.Date;

@DynamoDBTable(tableName = "DeviceValue")
public class DeviceValue implements Serializable {
    @Id
    private DeviceValueKey key;

    @DynamoDBAttribute(attributeName = "Value")
    private double value;

    @DynamoDBAttribute(attributeName = "LastChange")
    private Date lastChange;



    private DeviceValue(DeviceValueKey key, double value, Date lastChange) {
        this.key = key;
        this.value = value;
        this.lastChange = lastChange;
    }

    public DeviceValue(Long contextID, String tag, double value, Date lastChange) {
        this(new DeviceValueKey(contextID, tag), value, lastChange);
    }

    public DeviceValue() {}


    @DynamoDBHashKey(attributeName = "ContextID")
    public Long getContextID() {
        return (key != null) ? key.getContextID() : null;
    }

    public void setContextID(Long contextID) {
        if (key == null) {
            key = new DeviceValueKey();
        }
        key.setContextID(contextID);
    }

    @DynamoDBRangeKey(attributeName = "TAG")
    public String getTag() {
        return (key != null) ? key.getTag() : null;
    }

    public void setTag(String tag) {
        if (key == null) {
            key = new DeviceValueKey();
        }
        key.setTag(tag);
    }

    public double getValue() {
        return value;
    }

    public void setValue(double value) {
        this.value = value;
    }

    public Date getLastChange() {
        return lastChange;
    }

    public void setLastChange(Date lastChange) {
        this.lastChange = lastChange;
    }
}

B:

package com.somotic.scm.controller;

import com.amazonaws.auth.*;
import com.amazonaws.regions.Regions;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDB;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClientBuilder;
import org.socialsignin.spring.data.dynamodb.repository.config.EnableDynamoDBRepositories;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

@Configuration
@EnableDynamoDBRepositories(value = "com.somotic.scm.repo.nosql")
public class DynamoDBConfig {
    @Value("${amazon.aws.accesskey}")
    private String amazonAWSAccessKey;

    @Value("${amazon.aws.secretkey}")
    private String amazonAWSSecretKey;
    
    public AWSCredentialsProvider amazonAWSCredentialsProvider() {
        return new AWSStaticCredentialsProvider(amazonAWSCredentials());
    }

    @Bean
    public AWSCredentials amazonAWSCredentials() {
        return new BasicAWSCredentials(amazonAWSAccessKey, amazonAWSSecretKey);
    }

    @Bean
    public AmazonDynamoDB amazonDynamoDB() {
        return AmazonDynamoDBClientBuilder.standard()
                .withCredentials(amazonAWSCredentialsProvider())
                .withRegion(Regions.EU_CENTRAL_1)
                .build();
    }
}

C:

package com.somotic.scm.repo.nosql;

import com.somotic.scm.model.DeviceValue;
import com.somotic.scm.model.DeviceValueKey;
import org.socialsignin.spring.data.dynamodb.repository.EnableScan;
import org.springframework.data.repository.CrudRepository;

@EnableScan
public interface DeviceValueRepository extends CrudRepository<DeviceValue, DeviceValueKey> {

}

Specifications

• Spring Data DynamoDB Version: RELEASE
• Spring Data Version: RELEASE
• AWS SDK Version: RELEASE
• Java Version: 1.8
• Platform Details: Ubuntu Mate

[derjust]

Ok here we go - both repository factories try to register all repository interfaces with them -which doesn’t work very well. Especially because spring-boot does a lot of auto-magic behind the curtain via the implicit existing @EnableJpaRepositories.

The solution is to tell JPA and DynamoDB which repositories they are responsibility for (which then also drives which entities are registered):

For Spring-Boot:

@SpringBootApplication
@EnableJpaRepositories(
		includeFilters = {
		@ComponentScan.Filter(type = FilterType.ASSIGNABLE_TYPE, classes = {
				CustomerRepository.class}
		)}
)
@EnableDynamoDBRepositories(
		includeFilters = {
				@ComponentScan.Filter(type = FilterType.ASSIGNABLE_TYPE, classes = {
						DeviceValueRepository.class}
				)
		})
public class Application {

Same for a configuration class:

@Configuration
@EnableJpaRepositories(includeFilters = {
//or use basePackages or excludeFilters
	@ComponentScan.Filter(type = FilterType.ASSIGNABLE_TYPE, classes = {CustomerRepository.class})
})
@EnableDynamoDBRepositories(includeFilters = {
//or use basePackages or excludeFilters
	@ComponentScan.Filter(type = FilterType.ASSIGNABLE_TYPE, classes = {DeviceValueRepository.class})
})
public class AppConfig {

See also

• Using multiple datasources with Spring Boot and Spring Data
• Spring JPA – Multiple Databases

[BigDrakar]

Thanks @derjust! You’ve just made my day! However, I’ve just upgraded the spring-boot-starter-parent version to 2.0.0.RC1 (enabling spring-milestone repository) and everything has settled.