dbcp2 auto config is missing ability to set connectionProperties

[jbotuck]

Most of the setters in BasicDataSource can be configured from application.yml. https://commons.apache.org/proper/commons-dbcp/apidocs/org/apache/commons/dbcp2/BasicDataSource.html#setConnectionProperties-java.lang.String- cannot be configured.

Both Hikari and Tomcat have ways of configuring the properties that get sent to the driver but dbcp2 does not as this setter seems not to get registered by the @ConfigurationProperties annotation.

This limits the configurability of a dbcp2 datasource via spring boot

[snicoll]

Both Hikari and Tomcat have ways of configuring the properties that get sent to the driver but dbcp2 does not as this setter seems not to get registered by the @ConfigurationProperties annotation.

I am not sure what you mean by that but there is nothing that Spring Boot does specifically for Hikari or Tomcat. connectionProperties setter uses a String but the getter is a Properties. There is not much we can do about that I am afraid as we don't own the code.

Can we take a step back and can you describe what you're trying to do concretely?

[jbotuck]

I would like to configure the datasource with the property enableRowsetSupport=1.
The way I would like to do it is by setting a spring boot property. spring.datasource.dbcp2.connection-properties=enableRowsetSupport=1;
Spring boot allows this kind of configuration for both hikari and tomcat using spring.datasource.hikari.data-source-properties and spring.datasource.tomcat.connection-properties.

If its not possible to bring dbcp2 up to parity with the other datasources because dbcp2 violates the javabean spec then how should I configure these properties in a spring boot application?

[snicoll]

Spring boot allows this kind of configuration for both hikari and tomcat using spring.datasource.hikari.data-source-properties and spring.datasource.tomcat.connection-properties.

Again, as I've mentioned previously, there is nothing that Spring Boot does specifically for those two properties. Both Hikari and Tomcat exposes an accessor named "connection-properties" and that's about it.

If its not possible to bring dbcp2 up to parity with the other datasources because dbcp2 violates the javabean spec then how should I configure these properties in a spring boot application?

I've copy/pasted spring.datasource.dbcp2.connection-properties=enableRowsetSupport=1; in application.properties of a fresh app configured from start.spring.io and I can see via the debugger that BasicDataSource#setConnectionProperties is invoked with enableRowsetSupport=1;. It should be noted though that, because this property is unusual, there is no code assistance in the IDE.

I am going to close this now as there is no indication of a problem in Spring Boot.

[jbotuck]

Can we add the property to the documentation here? https://docs.spring.io/spring-boot/docs/current/reference/html/appendix-application-properties.html#data-properties.

I'd feel better about using this if it wasn't some undocumented feature that can be removed at any time.

[snicoll]

Can we add the property to the documentation here? https://docs.spring.io/spring-boot/docs/current/reference/html/appendix-application-properties.html#data-properties.

I am afraid we can't. Because it isn't really a valid property, it isn't detected and therefore not documented.

I'd feel better about using this if it wasn't some undocumented feature that can be removed at any time.

Documenting it wouldn't change anything to the fact that the DBCP2 project may decide to remove or change it at any time. We don't have any control on that.

[jbotuck]

Documenting it wouldn't change anything to the fact that the DBCP2 project may decide to remove or change it at any time. We don't have any control on that.

I'm more worried about whatever logic spring boot has for discovering setters at runtime suddenly becoming as strict as whatever logic spring boot has for discovering accessors when generating metadata.

[jbotuck]

I guess what I really want here is an additional entry here https://github.com/spring-projects/spring-boot/blob/master/spring-boot-project/spring-boot-autoconfigure/src/main/resources/META-INF/additional-spring-configuration-metadata.json for this property. But I get it if you don't want to do that.