Feature Request: Composite Objects

[mmadson]

Hi again,

This may be a bit outside the scope of what Owner should be able to do but I figured I'd throw it out there anyway.

@Config.Sources(...)
interface DbProperties extends Reloadable {

  @Key(...)
  String getJdbcUrl();

  @Key(...)
  String getJdbcUsername();

  @Key(...)
  String getJdbcPassword();

  @CompositePropertyProvider(DataSourceProvider.class)
  DataSource getDataSource()
}

class DataSourceProvider {
  DataSource create(properties) {
    return new DataSource(properties.getJdbcUrl()...);
  }
}

[lviggiano]

This looks very similar to what @ConverterClass is already doing.

But at the moment the instance of Converter cannot lookup on properties sources. When instantiating the Converter OWNER tries to invoke the default constructor. But, instead it could first try to see if a one-parameter constructor of type java.util.Properties is available, or if there is a one-parameter constructor accepting a subclass of org.aeonbits.Config, so that the ConverterClass can then access object properties as you are doing in your example in the DataSourceProvider.

I think this is a more convenient way than introducing a new annotation.

👍 Good suggestion.