Configuring default micronaut httpClient properties using ConfigurationProperties

Question

I am writing a java library module in Micronaut which has an httpClient. The idea is that my microservices will use this library as a jar dependency and use the httpClient.

Problem Statement : I want to configure my HttpClient without using application.yml.

Why don't I want to use application.yml ? - Because the microservices using this library will also have their own application.yml and when the jar is built, the two application.yml files will need to be merged. While technically possible, I don't want to use this approach.

Scenario - There is a boolean configuration property called micronaut.http.client.exception-on-error-status in micronaut that I need to set to false. I can easily set this in the application.yml as micronaut.http.client.exception-on-error-status=false but I want to avoid this approach due to aforementioned reasons. I want to set this in code.

I tried the following TWO approaches and neither of them worked.

Approach 1 - Using @ConfigurationProperties

I created the following MicronautHttpClientConfiguration.java class, but the property was NOT set.

import io.micronaut.context.annotation.ConfigurationProperties;

@ConfigurationProperties("micronaut.http.client")
public class MicronautHttpClientConfiguration {
    private boolean exceptionOnErrorStatus;

    public MicronautHttpClientConfiguration() {
        this.exceptionOnErrorStatus = false;
    }

    public boolean isExceptionOnErrorStatus() {
        return exceptionOnErrorStatus;
    }

    public void setExceptionOnErrorStatus(boolean exceptionOnErrorStatus) {
        this.exceptionOnErrorStatus = exceptionOnErrorStatus;
    }
}

Approach 2 - Using BeanCreatedEventListener

I created the following BeanCreatedEventListener to try and configure the HttpClient on creation, but was not able to.

import io.micronaut.context.event.BeanCreatedEvent;
import io.micronaut.context.event.BeanCreatedEventListener;
import io.micronaut.http.client.HttpClient;

import javax.inject.Singleton;

@Singleton
public class HttpClientBeanCreationEvent implements BeanCreatedEventListener<HttpClient> {
    @Override
    public HttpClient onCreated(BeanCreatedEvent<HttpClient> event) {
        HttpClient httpClient = event.getBean();
        // I have a handle on the HttpClient here, but not really sure how to set that property
        return httpClient;
    }
}

P.S. This problem is applicable to any HttpClient configuration (like read-timeout) or any default micronaut configuration for that matter.

UPDATE 1 : I am looking for a solution using @ConfigurationProperties as I realised that if I use approach 2 of BeanCreationEvent, Micronaut will never honour any configuration in application.yml (for this property) as BeanCreationEvent overrides all that. This will make it difficult for implementing microservices to override this property.

Answer 1

You should be creating a declarative client to expose to users and in the @Client annotation you can specify a configuration class