Add support for Vibur DBCP connection pool to DataSourceBuilder

[simeonmalchev]

Please add support / auto-configuration for Vibur DBCP connection pool (https://github.com/vibur/vibur-dbcp) in spring-boot.

Vibur DBCP is a concurrent, fast, and fully-featured JDBC connection pool, which has been around since 2013. The pool provides advanced performance monitoring capabilities, including slow SQL queries detection and logging, a non-starvation guarantee for application threads, statement caching, among other features.

Currently, spring-boot has built-in support for auto-configuration of the following jdbc connection pools in this order:

1. DataSourceConfiguration.Hikari.class,
2. DataSourceConfiguration.Tomcat.class
3. DataSourceConfiguration.Dbcp2.class
4. DataSourceConfiguration.OracleUcp.class

This issue is, in fact, to add Vibur DBCP to the above list. The Vibur DataSource class that needs to be instantiated is org.vibur.dbcp.ViburDBCPDataSource.class.

To the best of my understanding, adding support for Vibur will involve as a minimum changes in the DataSourceAutoConfiguration and DataSourceConfiguration classes from spring-boot-autoconfigure, and in the DataSourceBuilder class from spring-boot.

Note that Vibur requires its start() method to be called once the pool is configured. This method will validate the pool configuration. The pool also implements a close() method as part of its implementation of AutoClosebale.

If Vibur connection pool had to be instantiated from Java programming code, without the help of the spring.datasource.url, spring.datasource.username, spring.datasource.password, spring.datasource.driver-class-name properties, this could be done via something like:

    @Bean(initMethod = "start", destroyMethod = "close")
    @ConfigurationProperties(prefix = "spring.datasource.vibur")
    public DataSource dataSource() {
        return new ViburDBCPDataSource();
    }

The above snippet assumes that all Vibur config properties have a prefix of spring.datasource.vibur.
The disadvantage of such instantiation is that Vibur cannot utilize the mentioned earlier and standard for spring-boot 4 config properties with a prefix of spring.datasource. These 4 properties have to be repeated with a prefix of spring.datasource.vibur, where the url property needs be named jdbc-url as this is the name of the internal Vibur jdbc url property.

Disclaimer, I'm the author of Vibur DBCP. I'm happy to help with any questions which you may have about Vibur DBCP configuration or setup.

[snicoll]

Thanks for the suggestion.

As you may have seen, there is really two separate pieces to it:

• Support of DataSourceBuilder so that programmatic use of it would transparently configure your datasource, including when using spring.datasource.url & co when specifying a datasource type.
• Auto-configuration of a Viber DataSource if it's found on the classpath.

1 is a better place for your request, IMO. DataSourceBuilder has support for more pools such as C3P0, Oracle variants and the like. I've prototyped a quick hack that we can reuse if we want to pursue this.

[simeonmalchev]

@snicoll, thanks a lot for looking into this ticket and thanks for prototyping the hack.

I'm thinking that if only the changes from the first piece that is in the DataSourceBuilder class from spring-boot are implemented and the changes from the second piece that is in the DataSourceAutoConfiguration and DataSourceConfiguration classes from spring-boot-autoconfigure are not implemented, this will be confusing for the Vibur-DBCP users as they won't be able to configure Vibur connection pool via the application.properties or application.yml file.

Currently, the other connection pools are configured via the 4 properties with prefix spring.datasource (e.g., spring.datasource.url) plus the pool specific properties which have different prefix for each pool. E.g., for Tomcat pool the specific properties prefix is spring.datasource.tomcat for Hikari pool the specific properties prefix is spring.datasource.hikari, etc. I could see that these pool specific properties are defined in the inner static classes that are part of the DataSourceConfiguration class.

For Vibur pool I would imagine that the pool specific properties prefix can be spring.datasource.vibur, however, this implies that the changes in the spring-boot-autoconfigure project are done. Also, it seems to me that a static class in the DataSourceConfiguration is the perfect place where the Vibur pool start method can be invoked via something like:

    @Configuration(proxyBeanMethods = false)
    @ConditionalOnClass(org.vibur.dbcp.ViburDBCPDataSource.class)
    @ConditionalOnMissingBean(DataSource.class)
    @ConditionalOnProperty(name = "spring.datasource.type", havingValue = "org.vibur.dbcp.ViburDBCPDataSource", matchIfMissing = true)
    static class Vibur {
        @Bean
        @ConditionalOnMissingBean(PropertiesJdbcConnectionDetails.class)
        static ViburJdbcConnectionDetailsBeanPostProcessor viburJdbcConnectionDetailsBeanPostProcessor(
                ObjectProvider<JdbcConnectionDetails> connectionDetailsProvider) {
            return new ViburJdbcConnectionDetailsBeanPostProcessor(connectionDetailsProvider);
        }

        @Bean(initMethod = "start", destroyMethod = "close")
        @ConfigurationProperties(prefix = "spring.datasource.vibur")
        org.vibur.dbcp.ViburDBCPDataSource dataSource(DataSourceProperties properties,
                                                      JdbcConnectionDetails connectionDetails) {
            org.vibur.dbcp.ViburDBCPDataSource dataSource = createDataSource(connectionDetails, org.vibur.dbcp.ViburDBCPDataSource.class,
                    properties.getClassLoader());
            if (StringUtils.hasText(properties.getName())) {
                dataSource.setName(properties.getName());
            }
            return dataSource;
        }
    }

If I'm misunderstanding some details about the connection pool's configuration in a spring-boot application, please point me out where. If, in fact, you're saying that is possible Vibur pool to be easily configured (including its specific properties) and used in a spring-boot application with only the changes that you proposed yesterday, can you please show an example how to do that?

[snicoll]

@simeonmalchev please hold on until the team had a chance to review this.

If, in fact, you're saying that is possible Vibur pool to be easily configured (including its specific properties) and used in a spring-boot application with only the changes that you proposed yesterday, can you please show an example how to do that?

I never said that.

[simeonmalchev]

No problem at all.

[philwebb]

We discussed this today and we'd like to add support in the DataSourceBuilder but we're not keen to add any more auto-configured pools at this point.

I'll repurpose this issue and we'll merge @snicoll's prototype code later.

[simeonmalchev]

@philwebb, thanks for the update.

I'm trying to figure out what will be the best way to post-configure the Vibur DBCP pool specific properties after the support for it is added in the DataSourceBuilder. Would this be via a BeanPostProcessor's postProcessAfterInitialization(..) method, or there is some better way how to set these properties?