Kafka Kraft Mode support via confluent-local image

[scprek]

Fixes: #622

I attempted to do a separate class, similar to Redis vs RedisCluster mode. That approach did not work. I'm guessing because they were both of AbstractTestContainersProvider<KafkaContainer> and caused the KafkaKraftTestResourceProvider to always be ignored?

In KafkaTestResourceProvider I made sure to provide an empty list of properties if in Kraft Mode.

    @Override
    public List<String> getResolvableProperties(Map<String, Collection<String>> propertyEntries, Map<String, Object> testResourcesConfig) {
        return isKraftMode(testResourcesConfig) ? List.of() : SUPPORTED_PROPERTIES_LIST;
    }

New class

/*
 * Copyright 2017-2021 original authors
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package io.micronaut.testresources.kafka;

import io.micronaut.testresources.testcontainers.AbstractTestContainersProvider;
import org.testcontainers.containers.KafkaContainer;
import org.testcontainers.utility.DockerImageName;

import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Optional;

import static io.micronaut.testresources.kafka.KafkaConfigurationSupport.isKraftMode;
import static io.micronaut.testresources.kafka.KafkaTestResourceProvider.*;


/**
 * A test resource provider which will spawn a Kafka test container with Kraft mode enabled.
 * see: <a href="https://docs.confluent.io/platform/current/kafka-metadata/kraft.html#kraft-overview">Kafka Kraft Mode</a>
 */
public class KafkaKraftTestResourceProvider extends AbstractTestContainersProvider<KafkaContainer> {


    @Override
    public List<String> getResolvableProperties(Map<String, Collection<String>> propertyEntries, Map<String, Object> testResourcesConfig) {
        return isKraftMode(testResourcesConfig) ? SUPPORTED_PROPERTIES_LIST : List.of();
    }

    @Override
    public String getDisplayName() {
        return DISPLAY_NAME;
    }

    @Override
    protected String getSimpleName() {
        return SIMPLE_NAME;
    }

    @Override
    protected String getDefaultImageName() {
        return DEFAULT_IMAGE;
    }

    /**
     * Starts Kafka container in Kraft mode.
     * See: <a href="https://java.testcontainers.org/modules/kafka/#using-kraft-mode">TestContainers Kafka Kraft Mode</a>
     */
    @Override
    protected KafkaContainer createContainer(DockerImageName imageName, Map<String, Object> requestedProperties, Map<String, Object> testResourcesConfig) {
        return new KafkaContainer(imageName).withKraft();
    }

    @Override
    protected Optional<String> resolveProperty(String propertyName, KafkaContainer container) {
        return Optional.of(container.getBootstrapServers());
    }

    @Override
    protected boolean shouldAnswer(String propertyName, Map<String, Object> requestedProperties, Map<String, Object> testResourcesConfig) {
        return KAFKA_BOOTSTRAP_SERVERS.equals(propertyName);
    }
}

[scprek]

I attempted to do a separate class that leveraged the statics (e.g. display, simple name) in this class since they were the same.

That approach did not work. I'm guessing because they were both of AbstractTestContainersProvider<KafkaContainer> and caused the KafkaKraftTestResourceProvider to always be ignored?

[melix]

I think we should take a slightly different approach to fix a discrepancy. The base image is different whether you use kraft mode or not. However, we also have the generic property to override the base image, so the imageName that you get may be different from what getDefaultImageName() returns. Therefore, I would add a check if the image name has been changed, and if so, keep it (but still enable kraft mode on that changed image if needed).

Otherwise, you lose the ability to override the version of the kraft image.

[scprek]

@melix how do I check if the image name has been changed? I see how it's done in AbstractTestContainersProvider, but I cannot use TestContainerMetadataSupport inside KafkaTestResourceProvider because

'io. micronaut. testresources. testcontainers. TestContainerMetadataSupport' is not public in 'io. micronaut. testresources. testcontainers'. Cannot be accessed from outside package

[melix]

You have access to the imageName as a method parameter. I would compare it with getDefaultImageName()

[scprek]

Whoops 😅

[scprek]

@melix sure you are busy, just checking in especially on the alternative approach issue I hit.

[melix]

Hi @scprek , sorry I forgot about this PR.

[melix]

I think we should take a slightly different approach to fix a discrepancy. The base image is different whether you use kraft mode or not. However, we also have the generic property to override the base image, so the imageName that you get may be different from what getDefaultImageName() returns. Therefore, I would add a check if the image name has been changed, and if so, keep it (but still enable kraft mode on that changed image if needed).

Otherwise, you lose the ability to override the version of the kraft image.

[melix]

Thanks for the PR update!

[scprek]

Sorry it took so long! Was in micronaut-openapi space for a while ha.