如何配置多个数据库实例？

Question

我已经解决了这方面的现有问题，但仍然不满意。

要添加多个数据库配置，以下是我目前得到的信息 -

1) 更新 config.yml 文件 -

database1:
  driverClass: com.mysql.jdbc.Driver
  user: user1
  password: user!23
  url: jdbc:mysql://url.to.connect:3306/db1
  properties: charSet: UTF-8
  maxWaitForConnection: 1s
  validationQuery: "/* MyService Health Check */ SELECT 1"
  minSize: 8
  maxSize: 32
  checkConnectionWhileIdle: false
  checkConnectionHealthWhenIdleFor: 10s
  closeConnectionIfIdleFor: 1 minute

database2:
  driverClass: com.mysql.jdbc.Driver
  user: user2
  password: user!23
  url: jdbc:mysql://url.to.connect:3306/db2
  properties: charSet: UTF-8
  maxWaitForConnection: 1s
  validationQuery: "/* MyService Health Check */ SELECT 1"
  minSize: 8
  maxSize: 32
  checkConnectionWhileIdle: false
  checkConnectionHealthWhenIdleFor: 10s
  closeConnectionIfIdleFor: 1 minute

2) 将更改添加到 java 配置文件。

public class DropWizardConfiguration extends Configuration{

    @Valid
    @NotNull
    @JsonProperty
    private DatabaseConfiguration database1 = new DatabaseConfiguration();

    @Valid
    @NotNull
    @JsonProperty
    private DatabaseConfiguration database2 = new DatabaseConfiguration();

    public DatabaseConfiguration getDatabaseConfiguration1()
    {       
        return database1;
        }

        public DatabaseConfiguration getDatabaseConfiguration2()
    {       
        return database2;
        }
}

3) 在这一步中，我应该更新 DropWizard 服务以处理相应的数据库实例。

public class DropWizardService extends Service<DropWizardConfiguration>{
    private final HibernateBundle<DropWizardConfiguration> hibernate = new HibernateBundle<DropWizardConfiguration>(Game.class) {

        // @Override
        public DatabaseConfiguration getDatabaseConfiguration(DropWizardConfiguration configuration){
            return configuration.getDatabaseConfiguration();
        }
    };

    @Override
    public void initialize(Bootstrap<DropWizardConfiguration> bootstrap) {  
        bootstrap.addBundle(hibernate);
    }

    public void run() throws Exception{
        this.run(new String[]{"server", "./config.yml"});
    }

    @Override
    public void run(DropWizardConfiguration configuration, Environment environment) throws Exception {
        SessionFactory factory = hibernate.getSessionFactory();     
        environment.addResource(new MyResource(factory));   
    }   
}

但这是我要进入黑盒的地方，我不确定要更改什么配置或如何更改！

欣赏一些意见。

Answer 1

我最近不得不做一些类似的事情，我做的方式是使用 BeanDefinitionRegistryPostProcessor。我使用了 jdbcTemplates，但它应该可以转移到休眠会话。这样做是我能够添加任意数量的数据库，并且会创建 bean。然后只需在上下文文件中添加 bean。

我所做的是在配置中

@Valid
@NotNull
@JsonProperty("database")
private Collection<DataSourceConfig> databases;

public Collection<DataSourceConfig> getDatabase() {
    return databases;
}

这是我的 DataSourceConfig 类

public class DataSourceConfig {

@JsonProperty
private String name;

@JsonProperty
private String driverClassName;

@JsonProperty
private String username;

@JsonProperty
private String password;

@JsonProperty
private String url;

public String getDriverClassName() {
    return driverClassName;
}

public void setDriverClassName(String driverClassName) {
    this.driverClassName = driverClassName;
}

public String getUsername() {
    return username;
}

public void setUsername(String username) {
    this.username = username;
}

public String getPassword() {
    return password;
}

public void setPassword(String password) {
    this.password = password;
}

public String getUrl() {
    return url;
}

public void setUrl(String url) {
    this.url = url;
}

public String getName() {
    return name;
}

public void setName(String name) {
    this.name = name;
}
}

这是我的类中实现 BeanDefinitionPostProcessor 的方法

public void postProcessBeanDefinitionRegistry(BeanDefinitionRegistry registry) throws BeansException {

    /**
     * Builds JdbcTemplates for beans
     */
    Map<String,String> jdbcTemplateBeanNames = Maps.newHashMap();
    for (DataSourceConfig dsc : configuration.getDatabase()) {
        AbstractBeanDefinition jdbcTemplateDefinition = BeanDefinitionBuilder.rootBeanDefinition("org.springframework.jdbc.core.JdbcTemplate")
                .addPropertyValue("dataSource",
                        BeanDefinitionBuilder.genericBeanDefinition(DriverManagerDataSource.class)
                            .addPropertyValue("driverClassName", dsc.getDriverClassName())
                            .addPropertyValue("url", dsc.getUrl())
                            .addPropertyValue("username", dsc.getUsername())
                            .addPropertyValue("password", dsc.getPassword())
                            .getBeanDefinition()
                )
                .getBeanDefinition();
        String name = BeanDefinitionReaderUtils.registerWithGeneratedName(jdbcTemplateDefinition, registry);
        jdbcTemplateBeanNames.put(dsc.getName(), name);

    }