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Issue #003: Improve documentation of service documents

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This commit is contained in:
Markus Günther
2017-11-10 11:07:50 +01:00
parent 39d8891643
commit 89335ee919
10 changed files with 65 additions and 17 deletions
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42
gtd-codec/src/main/java/net/mguenther/gtd/kafka/serialization/ItemEventConverter.java
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@@ -14,22 +14,25 @@ import java.time.Instant;
import java.util.Date;
/**
* Converts bidirectionally between domain events and their respective Avro representation.
* This is a bit of a mess, but we have to cope with it due to the lack of polymorphy and
* inheritance in Avro.
*
* @author Markus Günther (markus.guenther@gmail.com)
* @author Boris Fresow (bfresow@gmail.com)
*/
@Component
public class ItemEventConverter {
private AvroItemEvent wrap(final ItemEvent event, final Object eventPayload) {
return AvroItemEvent
.newBuilder()
.setEventId(event.getEventId())
.setTimestamp(event.getTimestamp())
.setData(eventPayload)
.build();
}
/**
* Consumes a domain event of type {@code ItemEvent} and returns its corresponding
* Avro type (cf. {@code AvroItemEvent}).
*
* @param event
* the domain event that ought to be converted
* @return
* instance of {@code AvroItemEvent} that mirrors the domain event
*/
public AvroItemEvent from(final ItemEvent event) {
if (event instanceof ItemCreated) return from((ItemCreated) event);
@@ -111,6 +114,25 @@ public class ItemEventConverter {
return wrap(event, avroEvent);
}
private AvroItemEvent wrap(final ItemEvent event, final Object eventPayload) {
return AvroItemEvent
.newBuilder()
.setEventId(event.getEventId())
.setTimestamp(event.getTimestamp())
.setData(eventPayload)
.build();
}
/**
* Consumes an Avro event of type {@code AvroItemEvent} and returns its corresponding
* domain event (cf. {@code ItemEvent}).
*
* @param event
* the Avro event that ought to be converted
* @return
* instance of {@code ItemEvent} that mirrros the Avro event
*/
public ItemEvent to(final AvroItemEvent event) {
final String eventId = String.valueOf(event.getEventId());

3
gtd-codec/src/main/java/net/mguenther/gtd/kafka/serialization/ItemEventDeserializer.java
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@@ -11,6 +11,9 @@ import java.io.IOException;
import java.util.Map;
/**
* Simple {@code Deserializer} that operates on {@code AvroItemEvent}. This {@code Deserializer} does
* not support multiple versions of the same schema.
*
* @author Markus Günther (markus.guenther@gmail.com)
* @author Boris Fresow (bfresow@gmail.com)
*/

3
gtd-codec/src/main/java/net/mguenther/gtd/kafka/serialization/ItemEventSerializer.java
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@@ -12,6 +12,9 @@ import java.io.IOException;
import java.util.Map;
/**
* Simple {@code Serializer} that operates on {@code AvroItemEvent}. This {@code Serializer} does
* not support multiple versions of the same schema.
*
* @author Markus Günther (markus.guenther@gmail.com)
* @author Boris Fresow (bfresow@gmail.com)
*/

4
gtd-command-side/src/main/java/net/mguenther/gtd/domain/CommandHandler.java
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@@ -6,6 +6,10 @@ import java.util.List;
import java.util.concurrent.CompletableFuture;
/**
* Accepts a command (or a list of commands) and attempts to validate them against the current
* state of the referenced aggregate. If the validation holds, the {@code CommandHandler} emits
* corresponding events to the event log.
*
* @author Markus Günther (markus.guenther@gmail.com)
* @author Boris Fresow (bfresow@gmail.com)
*/

2
gtd-command-side/src/main/java/net/mguenther/gtd/domain/ItemEventPublisher.java
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@@ -3,6 +3,8 @@ package net.mguenther.gtd.domain;
import net.mguenther.gtd.domain.event.ItemEvent;
/**
* Publishes a given {@code ItemEvent} to an event log.
*
* @author Markus Günther (markus.guenther@gmail.com)
* @author Boris Fresow (bfresow@gmail.com)
*/

4
gtd-command-side/src/main/java/net/mguenther/gtd/kafka/ItemEventConsumer.java
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@@ -12,6 +12,10 @@ import org.springframework.kafka.support.Acknowledgment;
import org.springframework.stereotype.Component;
/**
* Consumes {@code AvroItemEvent}s that update the internal state of domain for the command-side. This is
* essential so that the validation that a {@code CommandHandler} performs always goes against the most
* recent state.
*
* @author Markus Günther (markus.guenther@gmail.com)
* @author Boris Fresow (bfresow@gmail.com)
*/

2
gtd-command-side/src/main/java/net/mguenther/gtd/kafka/TransactionalItemEventPublisher.java
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@@ -13,6 +13,8 @@ import org.springframework.kafka.support.SendResult;
import org.springframework.stereotype.Component;
/**
* Publisher for {@code ItemEvent}s that exhibits transactional guarantees.
*
* @author Markus Günther (markus.guenther@gmail.com)
* @author Boris Fresow (bfresow@gmail.com)
*/

1
gtd-command-side/src/main/java/net/mguenther/gtd/kafka/TransactionalItemEventPublisherConfig.java
View File

@@ -24,7 +24,6 @@ public class TransactionalItemEventPublisherConfig {
@Bean
public ProducerFactory<String, AvroItemEvent> producerFactory() {
final Map<String, Object> config = new HashMap<>();
// TODO (mgu): Extract to config value
config.put(ProducerConfig.BOOTSTRAP_SERVERS_CONFIG, "kafka:9092");
config.put(ProducerConfig.KEY_SERIALIZER_CLASS_CONFIG, StringSerializer.class);
config.put(ProducerConfig.VALUE_SERIALIZER_CLASS_CONFIG, ItemEventSerializer.class);

2
gtd-common/src/main/java/net/mguenther/gtd/domain/EventHandler.java
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@@ -5,6 +5,8 @@ import net.mguenther.gtd.domain.event.ItemEvent;
import java.util.concurrent.CompletableFuture;
/**
* Consumes {@code ItemEvent}s and acts upon them.
*
* @author Markus Günther (markus.guenther@gmail.com)
* @author Boris Fresow (bfresow@gmail.com)
*/

19
gtd-common/src/main/java/net/mguenther/gtd/domain/Item.java
View File

@@ -91,6 +91,13 @@ public class Item implements Serializable {
return associatedList;
}
/**
* Mutates the state of this {@code Item} in compliance with the given {@code ItemEvent}.
*
* @param event
* an event that occured in the system and that signals a change of state
* for the aggregate {@code Item}
*/
public void project(final ItemEvent event) {
if (event instanceof DueDateAssigned) project((DueDateAssigned) event);
else if (event instanceof RequiredTimeAssigned) project((RequiredTimeAssigned) event);
@@ -101,15 +108,15 @@ public class Item implements Serializable {
else throw new IllegalStateException("Unrecognized event: " + event.toString());
}
public void project(final DueDateAssigned event) {
private void project(final DueDateAssigned event) {
this.dueDate = event.getDueDate();
}
public void project(final RequiredTimeAssigned event) {
private void project(final RequiredTimeAssigned event) {
this.requiredTime = event.getRequiredTime();
}
public void project(final TagAssigned event) {
private void project(final TagAssigned event) {
synchronized (this) {
if (!tags.contains(event.getTag())) {
tags.add(event.getTag());
@@ -117,17 +124,17 @@ public class Item implements Serializable {
}
}
public void project(final TagRemoved event) {
private void project(final TagRemoved event) {
synchronized (this) {
tags.remove(event.getTag());
}
}
public void project(final ItemConcluded event) {
private void project(final ItemConcluded event) {
this.done = true;
}
public void project(final ItemMovedToList event) {
private void project(final ItemMovedToList event) {
this.associatedList = event.getList();
}
}