What to use instead of deprecated @ConfigPrefix("prefix") in quarkus

Question

I want to inject properties that have the same names but different prefixes in the application.properties file. For example :

application.properties :

greeting.message = hello
bye.message = bye

For this, the documentation suggests the following usage:

@ConfigProperties(prefix = "greeting")
public class GreetingConfiguration {

    @Size(min = 20)
    public String message;

}

@ApplicationScoped
public class SomeBean {

    @Inject 
    GreetingConfiguration greetingConfiguration;

    @ConfigPrefix("bye") 
    GreetingConfiguration byeConfiguration;

}

This way I can call greetingConfiguration.message and byeConfiguration message using the same variable (message).

But it's use is not recommended because @ConfigProperties and @ConfigPrefix annotations are deprecated.

It is recommended to use @ConfigMapping instead.

Likewise, How can I use different prefixes and properties with the same name without creating more than one variable (ex :- message) on the java side?

Answer 1

As per the document

With config mappings it is possible to group multiple configuration properties in a single interface that share the same prefix. A config mapping requires an interface with minimal metadata configuration and annotated with the @io.smallrye.config.ConfigMapping annotation.

Example(Same prefix),

application.properties

message.greeting= hello
message.bye= bye

Message Interface

import io.quarkus.runtime.annotations.StaticInitSafe;
import io.smallrye.config.ConfigMapping;

@StaticInitSafe
@ConfigMapping(prefix = "message")
interface Message {
    String greeting();

    String bye();
}

A config mapping interface can be injected into any CDI aware bean:

@Path("/backend/api/v1")
public class BackEndSecretResource {

    @Inject
    Message message;

    @GET
    public String get() {
        return message.greeting() + message.bye();
    }
}

---

This is not possible in the case of the same suffix because due to the below limitation.

 @Experimental("ConfigMapping API to group configuration properties")
    public @interface ConfigMapping {
        /**
         * The prefix of the configuration properties.
         *
         * @return the configuration property prefix
         */
        String prefix() default "";
    
        NamingStrategy namingStrategy() default NamingStrategy.KEBAB_CASE;
    
        enum NamingStrategy {
          
            VERBATIM,
          
            KEBAB_CASE,
          
            SNAKE_CASE
        }
    }

Means String suffix() unavailable. Still, yours is a rare scenario, maybe you can figure out other ways.

Note * @Experimental - Annotation that specifies that an element is experimental and may change without notice.

Refer - https://quarkus.io/guides/config-mappings

Refer - https://smallrye.io/docs/smallrye-config/main/mapping/mapping.html