spring-kafka notes

ManualConfiguration.java

import org.springframework.boot.autoconfigure.kafka.ConcurrentKafkaListenerContainerFactoryConfigurer;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.kafka.config.ConcurrentKafkaListenerContainerFactory;
import org.springframework.kafka.core.ConsumerFactory;
import org.springframework.kafka.listener.config.ContainerProperties;

import java.util.regex.Pattern;

@Configuration
public class ManualConfiguration{

    /**
     * This method will configure created factory with properties from environment.
     * @param configurer
     * @return
     */
    @Bean
    public ConcurrentKafkaListenerContainerFactory<Object, Object> kafkaListenerContainerFactory(
        ConcurrentKafkaListenerContainerFactoryConfigurer configurer
    ) {
        ConcurrentKafkaListenerContainerFactory<Object, Object> factory =
            new ConcurrentKafkaListenerContainerFactory<>();

        configurer.configure(factory, consumerFactory());

        return factory;
    }

    @Bean
    public ConsumerFactory<Object, Object> consumerFactory() {
        return null; //create consumer factory here
    }

    /**
     * I we need, we can create properties class filled with values from environment.
     * @return
     */
    @Bean
    @ConfigurationProperties(prefix = "spring.kafka.listener")
    ContainerProperties containerProperties() {
        return new ContainerProperties((Pattern) null);
    }
}