<groupId>org.apache.kafka</groupId>
<artifactId>kafka-clients</artifactId>
</dependency>
+ <dependency>
+ <groupId>org.springframework.kafka</groupId>
+ <artifactId>spring-kafka</artifactId>
+ </dependency>
<dependency>
<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
-import javax.annotation.PreDestroy;
-import java.util.List;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.TimeUnit;
-
@SpringBootApplication
@Slf4j
{
@Autowired
EndlessConsumer endlessConsumer;
- @Autowired
- ExecutorService executor;
@Override
endlessConsumer.start();
}
- @PreDestroy
- public void stopExecutor()
- {
- try
- {
- log.info("Shutting down the ExecutorService.");
- executor.shutdown();
- log.info("Waiting 5 seconds for the ExecutorService to terminate...");
- executor.awaitTermination(5, TimeUnit.SECONDS);
- }
- catch (InterruptedException e)
- {
- log.error("Exception while waiting for the termination of the ExecutorService: {}", e.toString());
- }
- finally
- {
- if (!executor.isShutdown())
- {
- log.warn("Forcing shutdown of ExecutorService!");
- executor
- .shutdownNow()
- .forEach(runnable -> log.warn("Unfinished task: {}", runnable.getClass().getSimpleName()));
- }
- log.info("Shutdow of ExecutorService finished");
- }
- }
-
public static void main(String[] args)
{
package de.juplo.kafka;
import org.apache.kafka.clients.consumer.ConsumerRecord;
-import org.apache.kafka.clients.consumer.KafkaConsumer;
-import org.apache.kafka.common.serialization.LongDeserializer;
-import org.apache.kafka.common.serialization.StringDeserializer;
+import org.springframework.boot.autoconfigure.kafka.KafkaProperties;
import org.springframework.boot.context.properties.EnableConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
+import org.springframework.kafka.core.ConsumerFactory;
-import java.util.Properties;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
import java.util.function.Consumer;
@Configuration
-@EnableConfigurationProperties(ApplicationProperties.class)
+@EnableConfigurationProperties({ KafkaProperties.class, ApplicationProperties.class })
public class ApplicationConfiguration
{
@Bean
- public Consumer<ConsumerRecord<String, Long>> consumer()
+ public Consumer<ConsumerRecord<String, ClientMessage>> consumer()
{
return (record) ->
{
}
@Bean
- public EndlessConsumer<String, Long> endlessConsumer(
- KafkaConsumer<String, Long> kafkaConsumer,
- ExecutorService executor,
- Consumer<ConsumerRecord<String, Long>> handler,
- ApplicationProperties properties)
+ public ApplicationErrorHandler errorHandler()
{
- return
- new EndlessConsumer<>(
- executor,
- properties.getClientId(),
- properties.getTopic(),
- kafkaConsumer,
- handler);
- }
-
- @Bean
- public ExecutorService executor()
- {
- return Executors.newSingleThreadExecutor();
+ return new ApplicationErrorHandler();
}
@Bean(destroyMethod = "close")
- public KafkaConsumer<String, Long> kafkaConsumer(ApplicationProperties properties)
+ public org.apache.kafka.clients.consumer.Consumer<String, ClientMessage> kafkaConsumer(ConsumerFactory<String, ClientMessage> factory)
{
- Properties props = new Properties();
-
- props.put("bootstrap.servers", properties.getBootstrapServer());
- props.put("group.id", properties.getGroupId());
- props.put("client.id", properties.getClientId());
- props.put("auto.offset.reset", properties.getAutoOffsetReset());
- props.put("metadata.max.age.ms", "1000");
- props.put("key.deserializer", StringDeserializer.class.getName());
- props.put("value.deserializer", LongDeserializer.class.getName());
-
- return new KafkaConsumer<>(props);
+ return factory.createConsumer();
}
}
--- /dev/null
+package de.juplo.kafka;
+
+import org.apache.kafka.clients.consumer.Consumer;
+import org.apache.kafka.clients.consumer.ConsumerRecord;
+import org.apache.kafka.clients.consumer.ConsumerRecords;
+import org.springframework.kafka.listener.CommonContainerStoppingErrorHandler;
+import org.springframework.kafka.listener.MessageListenerContainer;
+
+import java.util.List;
+import java.util.Optional;
+
+
+public class ApplicationErrorHandler extends CommonContainerStoppingErrorHandler
+{
+ private Exception exception;
+
+
+ public synchronized Optional<Exception> getException()
+ {
+ return Optional.ofNullable(exception);
+ }
+
+ public synchronized void clearException()
+ {
+ this.exception = null;
+ }
+
+
+ @Override
+ public void handleOtherException(
+ Exception thrownException, Consumer<?, ?> consumer,
+ MessageListenerContainer container,
+ boolean batchListener)
+ {
+ this.exception = thrownException;
+ super.handleOtherException(thrownException, consumer, container, batchListener);
+ }
+
+ @Override
+ public void handleRemaining(
+ Exception thrownException,
+ List<ConsumerRecord<?, ?>> records,
+ Consumer<?, ?> consumer,
+ MessageListenerContainer container)
+ {
+ this.exception = thrownException;
+ super.handleRemaining(thrownException, records, consumer, container);
+ }
+
+ @Override
+ public void handleBatch(
+ Exception thrownException,
+ ConsumerRecords<?, ?> data,
+ Consumer<?, ?> consumer,
+ MessageListenerContainer container,
+ Runnable invokeListener)
+ {
+ this.exception = thrownException;
+ super.handleBatch(thrownException, data, consumer, container, invokeListener);
+ }
+}
@Setter
public class ApplicationProperties
{
- @NotNull
- @NotEmpty
- private String bootstrapServer;
- @NotNull
- @NotEmpty
- private String groupId;
- @NotNull
- @NotEmpty
- private String clientId;
@NotNull
@NotEmpty
private String topic;
- @NotNull
- @NotEmpty
- private String autoOffsetReset;
}
--- /dev/null
+package de.juplo.kafka;
+
+import lombok.Data;
+
+
+@Data
+public class ClientMessage
+{
+ String client;
+ String message;
+}
import org.springframework.web.bind.annotation.ResponseStatus;
import org.springframework.web.bind.annotation.RestController;
+import java.util.HashMap;
import java.util.Map;
import java.util.concurrent.ExecutionException;
}
@PostMapping("stop")
- public void stop() throws ExecutionException, InterruptedException
+ public void stop()
{
consumer.stop();
}
@GetMapping("seen")
public Map<Integer, Map<String, Long>> seen()
{
- return consumer.getSeen();
+ return new HashMap<>();
}
@ExceptionHandler
import lombok.RequiredArgsConstructor;
import lombok.extern.slf4j.Slf4j;
-import org.apache.kafka.clients.consumer.*;
+import org.apache.kafka.clients.consumer.ConsumerRecord;
import org.apache.kafka.common.TopicPartition;
-import org.apache.kafka.common.errors.RecordDeserializationException;
-import org.apache.kafka.common.errors.WakeupException;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.kafka.annotation.KafkaListener;
+import org.springframework.kafka.config.KafkaListenerEndpointRegistry;
+import org.springframework.kafka.listener.ConsumerAwareRebalanceListener;
+import org.springframework.stereotype.Component;
-import javax.annotation.PreDestroy;
-import java.time.Duration;
-import java.util.*;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.locks.Condition;
-import java.util.concurrent.locks.Lock;
-import java.util.concurrent.locks.ReentrantLock;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+import java.util.Optional;
+import java.util.function.Consumer;
+@Component
@Slf4j
@RequiredArgsConstructor
-public class EndlessConsumer<K, V> implements ConsumerRebalanceListener, Runnable
+public class EndlessConsumer<K, V> implements ConsumerAwareRebalanceListener
{
- private final ExecutorService executor;
- private final String id;
- private final String topic;
- private final Consumer<K, V> consumer;
- private final java.util.function.Consumer<ConsumerRecord<K, V>> handler;
+ @Autowired
+ private KafkaListenerEndpointRegistry registry;
+ @Value("${spring.kafka.consumer.client-id}")
+ String id;
+ @Autowired
+ Consumer<ConsumerRecord<K, V>> handler;
+ @Autowired
+ ApplicationErrorHandler errorHandler;
- private final Lock lock = new ReentrantLock();
- private final Condition condition = lock.newCondition();
- private boolean running = false;
- private Exception exception;
private long consumed = 0;
private final Map<Integer, Map<String, Long>> seen = new HashMap<>();
@Override
- public void onPartitionsRevoked(Collection<TopicPartition> partitions)
+ public void onPartitionsRevokedBeforeCommit(
+ org.apache.kafka.clients.consumer.Consumer<?, ?> consumer,
+ Collection<TopicPartition> partitions)
{
partitions.forEach(tp ->
{
}
@Override
- public void onPartitionsAssigned(Collection<TopicPartition> partitions)
+ public void onPartitionsAssigned(
+ org.apache.kafka.clients.consumer.Consumer<?, ?> consumer,
+ Collection<TopicPartition> partitions)
{
partitions.forEach(tp ->
{
}
- @Override
- public void run()
- {
- try
- {
- log.info("{} - Subscribing to topic {}", id, topic);
- consumer.subscribe(Arrays.asList(topic), this);
-
- while (true)
- {
- ConsumerRecords<K, V> records =
- consumer.poll(Duration.ofSeconds(1));
-
- // Do something with the data...
- log.info("{} - Received {} messages", id, records.count());
- for (ConsumerRecord<K, V> record : records)
- {
- log.info(
- "{} - {}: {}/{} - {}={}",
- id,
- record.offset(),
- record.topic(),
- record.partition(),
- record.key(),
- record.value()
- );
-
- handler.accept(record);
-
- consumed++;
-
- Integer partition = record.partition();
- String key = record.key() == null ? "NULL" : record.key().toString();
- Map<String, Long> byKey = seen.get(partition);
-
- if (!byKey.containsKey(key))
- byKey.put(key, 0l);
-
- long seenByKey = byKey.get(key);
- seenByKey++;
- byKey.put(key, seenByKey);
- }
- }
- }
- catch(WakeupException e)
- {
- log.info("{} - RIIING! Request to stop consumption - commiting current offsets!", id);
- consumer.commitSync();
- shutdown();
- }
- catch(RecordDeserializationException e)
- {
- TopicPartition tp = e.topicPartition();
- long offset = e.offset();
- log.error(
- "{} - Could not deserialize message on topic {} with offset={}: {}",
- id,
- tp,
- offset,
- e.getCause().toString());
-
- consumer.commitSync();
- shutdown(e);
- }
- catch(Exception e)
- {
- log.error("{} - Unexpected error: {}", id, e.toString(), e);
- shutdown(e);
- }
- finally
- {
- log.info("{} - Consumer-Thread exiting", id);
- }
- }
-
- private void shutdown()
- {
- shutdown(null);
- }
-
- private void shutdown(Exception e)
- {
- lock.lock();
- try
- {
- try
- {
- log.info("{} - Unsubscribing from topic {}", id, topic);
- consumer.unsubscribe();
- }
- catch (Exception ue)
- {
- log.error(
- "{} - Error while unsubscribing from topic {}: {}",
- id,
- topic,
- ue.toString());
- }
- finally
- {
- running = false;
- exception = e;
- condition.signal();
- }
- }
- finally
- {
- lock.unlock();
- }
- }
-
- public Map<Integer, Map<String, Long>> getSeen()
+ @KafkaListener(
+ id = "${spring.kafka.consumer.client-id}",
+ idIsGroup = false,
+ topics = "${consumer.topic}",
+ autoStartup = "false")
+ public void receive(ConsumerRecord<K, V> record)
{
- return seen;
+ log.info(
+ "{} - {}: {}/{} - {}={}",
+ id,
+ record.offset(),
+ record.topic(),
+ record.partition(),
+ record.key(),
+ record.value()
+ );
+
+ handler.accept(record);
+
+ consumed++;
}
- public void start()
- {
- lock.lock();
- try
- {
- if (running)
- throw new IllegalStateException("Consumer instance " + id + " is already running!");
-
- log.info("{} - Starting - consumed {} messages before", id, consumed);
- running = true;
- exception = null;
- executor.submit(this);
- }
- finally
- {
- lock.unlock();
- }
- }
- public synchronized void stop() throws ExecutionException, InterruptedException
+ public synchronized void start()
{
- lock.lock();
- try
- {
- if (!running)
- throw new IllegalStateException("Consumer instance " + id + " is not running!");
+ if (registry.getListenerContainer(id).isChildRunning())
+ throw new IllegalStateException("Consumer instance " + id + " is already running!");
- log.info("{} - Stopping", id);
- consumer.wakeup();
- condition.await();
- log.info("{} - Stopped - consumed {} messages so far", id, consumed);
- }
- finally
- {
- lock.unlock();
- }
+ log.info("{} - Starting - consumed {} messages before", id, consumed);
+ errorHandler.clearException();
+ registry.getListenerContainer(id).start();
}
- @PreDestroy
- public void destroy() throws ExecutionException, InterruptedException
+ public synchronized void stop()
{
- log.info("{} - Destroy!", id);
- try
- {
- stop();
- }
- catch (IllegalStateException e)
- {
- log.info("{} - Was already stopped", id);
- }
- catch (Exception e)
- {
- log.error("{} - Unexpected exception while trying to stop the consumer", id, e);
- }
- finally
- {
- log.info("{}: Consumed {} messages in total, exiting!", id, consumed);
- }
- }
+ if (!registry.getListenerContainer(id).isChildRunning())
+ throw new IllegalStateException("Consumer instance " + id + " is not running!");
- public boolean running()
- {
- lock.lock();
- try
- {
- return running;
- }
- finally
- {
- lock.unlock();
- }
+ log.info("{} - Stopping", id);
+ registry.getListenerContainer(id).stop();
+ log.info("{} - Stopped - consumed {} messages so far", id, consumed);
}
- public Optional<Exception> exitStatus()
+ public synchronized Optional<Exception> exitStatus()
{
- lock.lock();
- try
- {
- if (running)
- throw new IllegalStateException("No exit-status available: Consumer instance " + id + " is running!");
+ if (registry.getListenerContainer(id).isChildRunning())
+ throw new IllegalStateException("No exit-status available: Consumer instance " + id + " is running!");
- return Optional.ofNullable(exception);
- }
- finally
- {
- lock.unlock();
- }
+ return errorHandler.getException();
}
}
consumer:
- bootstrap-server: :9092
- group-id: my-group
- client-id: DEV
topic: test
- auto-offset-reset: earliest
management:
endpoint:
shutdown:
enabled: true
info:
kafka:
- bootstrap-server: ${consumer.bootstrap-server}
- client-id: ${consumer.client-id}
- group-id: ${consumer.group-id}
+ bootstrap-server: ${spring.kafka.consumer.bootstrap-servers}
+ client-id: ${spring.kafka.consumer.client-id}
+ group-id: ${spring.kafka.consumer.group-id}
topic: ${consumer.topic}
- auto-offset-reset: ${consumer.auto-offset-reset}
+ auto-offset-reset: ${spring.kafka.consumer.auto-offset-reset}
+spring:
+ kafka:
+ consumer:
+ bootstrap-servers: :9092
+ client-id: DEV
+ auto-offset-reset: earliest
+ group-id: my-group
+ value-deserializer: org.springframework.kafka.support.serializer.JsonDeserializer
+ properties:
+ spring.json.type.mapping: "message:de.juplo.kafka.ClientMessage"
+ spring.json.trusted.packages: "de.juplo.kafka"
logging:
level:
root: INFO
<logger name="de.juplo" level="TRACE"/>
<!-- logger name="org.apache.kafka.clients" level="DEBUG" / -->
+ <logger name="org.springframework.kafka" level="DEBUG"/>
<root level="INFO">
<appender-ref ref="STDOUT" />
import org.apache.kafka.common.utils.Bytes;
import org.junit.jupiter.api.*;
import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.autoconfigure.kafka.KafkaAutoConfiguration;
+import org.springframework.boot.autoconfigure.kafka.KafkaProperties;
import org.springframework.boot.test.context.ConfigDataApplicationContextInitializer;
import org.springframework.boot.test.context.TestConfiguration;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Import;
+import org.springframework.context.annotation.Primary;
+import org.springframework.kafka.support.serializer.JsonSerializer;
import org.springframework.kafka.test.context.EmbeddedKafka;
import org.springframework.test.context.TestPropertySource;
import org.springframework.test.context.junit.jupiter.SpringJUnitConfig;
import java.time.Duration;
import java.util.*;
import java.util.concurrent.ExecutionException;
-import java.util.concurrent.ExecutorService;
import java.util.function.BiConsumer;
+import java.util.function.BiFunction;
import java.util.function.Consumer;
-import java.util.function.Function;
import java.util.stream.Collectors;
import java.util.stream.IntStream;
import static org.awaitility.Awaitility.*;
-@SpringJUnitConfig(initializers = ConfigDataApplicationContextInitializer.class)
+@SpringJUnitConfig(
+ initializers = ConfigDataApplicationContextInitializer.class,
+ classes = {
+ EndlessConsumer.class,
+ KafkaAutoConfiguration.class,
+ ApplicationTests.Configuration.class })
@TestMethodOrder(MethodOrderer.OrderAnnotation.class)
@TestPropertySource(
properties = {
- "consumer.bootstrap-server=${spring.embedded.kafka.brokers}",
+ "spring.kafka.consumer.bootstrap-servers=${spring.embedded.kafka.brokers}",
"consumer.topic=" + TOPIC })
@EmbeddedKafka(topics = TOPIC, partitions = PARTITIONS)
@Slf4j
@Autowired
KafkaProducer<String, Bytes> kafkaProducer;
@Autowired
- KafkaConsumer<String, Long> kafkaConsumer;
+ org.apache.kafka.clients.consumer.Consumer<String, ClientMessage> kafkaConsumer;
@Autowired
KafkaConsumer<Bytes, Bytes> offsetConsumer;
@Autowired
- ApplicationProperties properties;
+ ApplicationProperties applicationProperties;
@Autowired
- ExecutorService executor;
+ KafkaProperties kafkaProperties;
+ @Autowired
+ EndlessConsumer endlessConsumer;
+ @Autowired
+ RecordHandler recordHandler;
- Consumer<ConsumerRecord<String, Long>> testHandler;
- EndlessConsumer<String, Long> endlessConsumer;
Map<TopicPartition, Long> oldOffsets;
Map<TopicPartition, Long> newOffsets;
- Set<ConsumerRecord<String, Long>> receivedRecords;
+ Set<ConsumerRecord<String, ClientMessage>> receivedRecords;
/** Tests methods */
@Order(1) // << The poistion pill is not skipped. Hence, this test must run first
void commitsCurrentOffsetsOnSuccess() throws ExecutionException, InterruptedException
{
- send100Messages(i -> new Bytes(valueSerializer.serialize(TOPIC, i)));
+ send100Messages((key, counter) -> serialize(key, counter));
await("100 records received")
.atMost(Duration.ofSeconds(30))
@Order(2)
void commitsOffsetOfErrorForReprocessingOnError()
{
- send100Messages(counter ->
+ send100Messages((key, counter) ->
counter == 77
? new Bytes(stringSerializer.serialize(TOPIC, "BOOM!"))
- : new Bytes(valueSerializer.serialize(TOPIC, counter)));
-
- await("Consumer failed")
- .atMost(Duration.ofSeconds(30))
- .until(() -> !endlessConsumer.running());
-
- checkSeenOffsetsForProgress();
- compareToCommitedOffsets(newOffsets);
+ : serialize(key, counter));
- endlessConsumer.start();
await("Consumer failed")
.atMost(Duration.ofSeconds(30))
- .until(() -> !endlessConsumer.running());
+ .untilAsserted(() -> checkSeenOffsetsForProgress());
- checkSeenOffsetsForProgress();
compareToCommitedOffsets(newOffsets);
assertThat(receivedRecords.size())
.describedAs("Received not all sent events")
.describedAs("Consumer should not be running")
.isThrownBy(() -> endlessConsumer.exitStatus());
assertThat(endlessConsumer.exitStatus())
- .describedAs("Consumer should have exited abnormally")
- .containsInstanceOf(RecordDeserializationException.class);
+ .containsInstanceOf(RecordDeserializationException.class)
+ .describedAs("Consumer should have exited abnormally");
}
}
- void send100Messages(Function<Long, Bytes> messageGenerator)
+ void send100Messages(BiFunction<Integer, Long, Bytes> messageGenerator)
{
long i = 0;
{
for (int key = 0; key < 10; key++)
{
- Bytes value = messageGenerator.apply(++i);
+ Bytes value = messageGenerator.apply(key, ++i);
ProducerRecord<String, Bytes> record =
new ProducerRecord<>(
Integer.toString(key%2),
value);
+ record.headers().add("__TypeId__", "message".getBytes());
kafkaProducer.send(record, (metadata, e) ->
{
if (metadata != null)
}
}
+ Bytes serialize(Integer key, Long value)
+ {
+ ClientMessage message = new ClientMessage();
+ message.setClient(key.toString());
+ message.setMessage(value.toString());
+ return new Bytes(valueSerializer.serialize(TOPIC, message));
+ }
+
@BeforeEach
public void init()
{
- testHandler = record -> {} ;
+ recordHandler.testHandler = (record) -> {};
oldOffsets = new HashMap<>();
newOffsets = new HashMap<>();
newOffsets.put(tp, offset - 1);
});
- Consumer<ConsumerRecord<String, Long>> captureOffsetAndExecuteTestHandler =
+ recordHandler.captureOffsets =
record ->
{
+ receivedRecords.add(record);
newOffsets.put(
new TopicPartition(record.topic(), record.partition()),
record.offset());
- receivedRecords.add(record);
- testHandler.accept(record);
};
- endlessConsumer =
- new EndlessConsumer<>(
- executor,
- properties.getClientId(),
- properties.getTopic(),
- kafkaConsumer,
- captureOffsetAndExecuteTestHandler);
-
endlessConsumer.start();
}
}
}
+ public static class RecordHandler implements Consumer<ConsumerRecord<String, ClientMessage>>
+ {
+ Consumer<ConsumerRecord<String, ClientMessage>> captureOffsets;
+ Consumer<ConsumerRecord<String, ClientMessage>> testHandler;
+
+
+ @Override
+ public void accept(ConsumerRecord<String, ClientMessage> record)
+ {
+ captureOffsets
+ .andThen(testHandler)
+ .accept(record);
+ }
+ }
@TestConfiguration
@Import(ApplicationConfiguration.class)
public static class Configuration
{
+ @Primary
+ @Bean
+ public Consumer<ConsumerRecord<String, ClientMessage>> testHandler()
+ {
+ return new RecordHandler();
+ }
+
@Bean
- Serializer<Long> serializer()
+ Serializer<ClientMessage> serializer()
{
- return new LongSerializer();
+ return new JsonSerializer<>();
}
@Bean
- KafkaProducer<String, Bytes> kafkaProducer(ApplicationProperties properties)
+ KafkaProducer<String, Bytes> kafkaProducer(KafkaProperties properties)
{
Properties props = new Properties();
- props.put("bootstrap.servers", properties.getBootstrapServer());
+ props.put("bootstrap.servers", properties.getConsumer().getBootstrapServers());
props.put("linger.ms", 100);
props.put("key.serializer", StringSerializer.class.getName());
props.put("value.serializer", BytesSerializer.class.getName());
}
@Bean
- KafkaConsumer<Bytes, Bytes> offsetConsumer(ApplicationProperties properties)
+ KafkaConsumer<Bytes, Bytes> offsetConsumer(KafkaProperties properties)
{
Properties props = new Properties();
- props.put("bootstrap.servers", properties.getBootstrapServer());
+ props.put("bootstrap.servers", properties.getConsumer().getBootstrapServers());
props.put("client.id", "OFFSET-CONSUMER");
- props.put("group.id", properties.getGroupId());
+ props.put("group.id", properties.getConsumer().getGroupId());
props.put("key.deserializer", BytesDeserializer.class.getName());
props.put("value.deserializer", BytesDeserializer.class.getName());
projects / demos / kafka / training / commitdiff