SpringBootAdminClientAutoConfiguration required a single bean, but 2 were found

[ffroliva]

Spring Boot Admin Server information

• Version: 3.1.0

• Spring Boot version: 3.1.0

• Configured Security: basic auth

• Webflux or Servlet application: servlet applicatoin

Client information

• Spring Boot versions: 3.1.0

• Used discovery mechanism: self-registration

• Webflux or Servlet application: servlet

Description

I need to customize RegistrationClient and for that, I have created a Configuration classes as follows:

import de.codecentric.boot.admin.client.config.ClientProperties;
import de.codecentric.boot.admin.client.registration.BlockingRegistrationClient;
import de.codecentric.boot.admin.client.registration.RegistrationClient;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.boot.ssl.NoSuchSslBundleException;
import org.springframework.boot.ssl.SslBundle;
import org.springframework.boot.ssl.SslBundles;
import org.springframework.boot.web.client.RestTemplateBuilder;
import org.springframework.boot.web.client.RestTemplateCustomizer;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.annotation.Import;
import org.springframework.context.annotation.Primary;
import org.springframework.web.client.RestTemplate;

@Slf4j
@Configuration
@Import({ClientProperties.class})
public class RestTemplateConfiguration {

    public static final String MY_SSL_BUNDLE = "my_ssl_bundle";

    RestTemplateBuilder customRestTemplateBuilder(RestTemplateBuilder restTemplateBuilder, SslBundles sslBundles) {
        if (sslBundles != null) {
            try {
                SslBundle sslBundle = sslBundles.getBundle(MY_SSL_BUNDLE);
                restTemplateBuilder.setSslBundle(sslBundle);
                log.info("Found 'spring.ssl.bundle.jks.my_ssl_bundle.*' bundle, setting it to RestTemplateBuilder");
            } catch (NoSuchSslBundleException ex) {
                log.info("SSL not enabled. 'spring.ssl.bundle.jks.my_ssl_bundle.*' not provided on the configurations.");
                log.info("Creating RestTemplate with no SSL configurations.");
            }
        }
        return restTemplateBuilder;
    }

    @Bean
    @Primary
    public RegistrationClient registrationClient(@Qualifier("de.codecentric.boot.admin.client.config.ClientProperties") ClientProperties client, SslBundles sslBundles) {
        RestTemplateBuilder builder = (new RestTemplateBuilder(new RestTemplateCustomizer[0])).setConnectTimeout(client.getConnectTimeout());
        builder.setReadTimeout(client.getReadTimeout());
        if (client.getUsername() != null && client.getPassword() != null) {
            builder = builder.basicAuthentication(client.getUsername(), client.getPassword());
        }

        RestTemplate build = customRestTemplateBuilder(builder, sslBundles).build();
        return new BlockingRegistrationClient(build);
    }

    /**
     * @return a new customized ResTemplate instance
     */
    @Bean
    public RestTemplate restTemplate(RestTemplateBuilder restTemplateBuilder, SslBundles sslBundles) {
        return customRestTemplateBuilder(restTemplateBuilder, sslBundles).build();
    }
}

When I start the application I get the following error:

Parameter 1 of method registrator in de.codecentric.boot.admin.client.config.SpringBootAdminClientAutoConfiguration required a single bean, but 2 were found:

• de.codecentric.boot.admin.client.config.ClientProperties: defined in unknown location
• spring.boot.admin.client-de.codecentric.boot.admin.client.config.ClientProperties: defined in unknown location

[hzpz]

Hey @ffroliva, this is a Spring related issue (not Spring Boot Admin). Spring Boot Admin already provides an instance of ClientProperties (see @EnableConfigurationProperties in SpringBootAdminClientAutoConfiguration). If you @Import ClientProperties again, there will be another instance of this class and this is what the error message is about.

Just remove the line @Import({ClientProperties.class}) and it should work. Please let us know if that helps.

[ffroliva]

Dear Timo,

I have added the @.***and removed the @Import({ClientProperties.class})`. It worked.

I wonder if the approach I am taking is the best approach to customize the RegistrationClient with SSL configuration. Do you suggest any alternative solution?

Thank you in advance.

Regards,

Flavio Oliva

Em sex., 19 de abr. de 2024 às 07:35, Timo @.***> escreveu:

Hey @ffroliva https://github.com/ffroliva, this is a Spring related issue (not Spring Boot Admin). Spring Boot Admin already provides an instance of ClientProperties (see @EnableConfigurationProperties in SpringBootAdminClientAutoConfiguration). If you @Import ClientProperties again, there will be another instance of this class and this is what the error message is about.

Just remove the line @Import({ClientProperties.class}) and it should work. Please let us know if that helps.

— Reply to this email directly, view it on GitHub https://github.com/codecentric/spring-boot-admin/issues/3312#issuecomment-2065855069, or unsubscribe https://github.com/notifications/unsubscribe-auth/AF67VGZNFH24DFVT4IFERQLY6C3MRAVCNFSM6AAAAABGLMINJ2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDANRVHA2TKMBWHE . You are receiving this because you were mentioned.Message ID: @.***>

[hzpz]

Hey @ffroliva, right now it seems that this is the only way to customize the RegistrationClient. We are considering changing our auto-configuration so that it'll be easier to customize and/or implement a property to customize the SSL bundle.

[ffroliva]

Thank you @Timo

Looking forward to this enhancement.

BTW, spring boot admin is a great project. Well done!

You may close this thread if you understand so.

Regards,

Flavio

Em sex., 19 de abr. de 2024 às 12:51, Timo @.***> escreveu:

Hey @ffroliva https://github.com/ffroliva, right now it seems that this is the only way to customize the RegistrationClient. We are considering changing our auto-configuration so that it'll be easier to customize and/or implement a property to customize the SSL bundle.

— Reply to this email directly, view it on GitHub https://github.com/codecentric/spring-boot-admin/issues/3312#issuecomment-2066410988, or unsubscribe https://github.com/notifications/unsubscribe-auth/AF67VG65VHHHBBB4VYEWTG3Y6EAN5AVCNFSM6AAAAABGLMINJ2VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDANRWGQYTAOJYHA . You are receiving this because you were mentioned.Message ID: @.***>

[hzpz]

Thanks! We will mention this issue if we implement any of the enhancements.