DATAREDIS-1179 - Allow reuse of RedisConverter in ObjectHashMapper.

Original pull request: spring-projects#548.

Author: christophstrobl

src/main/asciidoc/reference/redis-streams.adoc

@@ -293,3 +293,37 @@ redisTemplate()
  .add(record); <1>
 ----
 <1> XADD user-logon * "firstname" "night" "@class" "com.example.User" "lastname" "angel"
+
+[NOTE]
+====
+A `StreamMessageListenerContainer` may not be aware of any `@TypeAlias` used on domain types as those need to be resolved via a `MappingContext`. So please make sure to pre initialize the `RedisMappingContext` with the `initialEntitySet`.
+
+[source,java]
+----
+@Bean
+RedisMappingContext redisMappingContext() {
+RedisMappingContext ctx = new RedisMappingContext();
+ctx.setInitialEntitySet(Collections.singleton(Person.class));
+return ctx;
+}
+
+@Bean
+RedisConverter redisConverter(RedisMappingContext mappingContext) {
+return new MappingRedisConverter(mappingContext, null, null);
+}
+
+@Bean
+ObjectHashMapper hashMapper(RedisConverter converter) {
+return new ObjectHashMapper(converter);
+}
+
+@Bean
+StreamMessageListenerContainer streamMessageListenerContainer(RedisConnectionFactory connectionFactory, ObjectHashMapper hashMapper) {
+StreamMessageListenerContainerOptions<String, ObjectRecord<String, Object>> options = StreamMessageListenerContainerOptions.builder()
+.objectMapper(hashMapper)
+.build();
+
+return StreamMessageListenerContainer.create(connectionFactory, options);
+}
+----
+====

src/main/java/org/springframework/data/redis/hash/ObjectHashMapper.java

@@ -16,24 +16,21 @@
 package org.springframework.data.redis.hash;
 
 import java.util.Collections;
-import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Set;
 
-import org.springframework.core.convert.ConverterNotFoundException;
-import org.springframework.data.mapping.PropertyPath;
-import org.springframework.data.mapping.PropertyReferenceException;
 import org.springframework.data.redis.core.convert.CustomConversions;
 import org.springframework.data.redis.core.convert.IndexResolver;
 import org.springframework.data.redis.core.convert.IndexedData;
 import org.springframework.data.redis.core.convert.MappingRedisConverter;
+import org.springframework.data.redis.core.convert.RedisConverter;
 import org.springframework.data.redis.core.convert.RedisCustomConversions;
 import org.springframework.data.redis.core.convert.RedisData;
 import org.springframework.data.redis.core.convert.ReferenceResolver;
 import org.springframework.data.redis.core.mapping.RedisMappingContext;
-import org.springframework.data.redis.core.mapping.RedisPersistentEntity;
 import org.springframework.data.util.TypeInformation;
 import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
 
 /**
  * {@link HashMapper} based on {@link MappingRedisConverter}. Supports nested properties and simple types like
@@ -74,7 +71,7 @@
  */
 public class ObjectHashMapper implements HashMapper<Object, byte[], byte[]> {
 
-private final MappingRedisConverter converter;
+private final RedisConverter converter;
 
 /**
  * Creates new {@link ObjectHashMapper}.
@@ -110,6 +107,19 @@ public ObjectHashMapper(@Nullable org.springframework.data.convert.CustomConvers
 converter = mappingConverter;
 }
 
+/**
+ * Creates a new {@link ObjectHashMapper} using the given {@link RedisConverter} for conversion.
+ *
+ * @param converter must not be {@literal null}.
+ * @throws IllegalArgumentException if the given {@literal converter} is {@literal null}.
+ * @since 2.4
+ */
+public ObjectHashMapper(RedisConverter converter) {
+
+Assert.notNull(converter, "Converter must not be null!");
+this.converter = converter;
+}
+
 /*
  * (non-Javadoc)
  * @see org.springframework.data.redis.hash.HashMapper#toHash(java.lang.Object)

src/test/java/org/springframework/data/redis/mapping/ObjectHashMapperTests.java

@@ -17,10 +17,15 @@
 
 import static org.assertj.core.api.Assertions.*;
 
+import lombok.Data;
+
+import java.util.Collections;
 import java.util.Map;
 
 import org.junit.Test;
-
+import org.springframework.data.annotation.TypeAlias;
+import org.springframework.data.redis.core.convert.MappingRedisConverter;
+import org.springframework.data.redis.core.mapping.RedisMappingContext;
 import org.springframework.data.redis.hash.ObjectHashMapper;
 
 /**
@@ -57,4 +62,29 @@ public void fromHashShouldFailIfTypeDoesNotMatch() {
 
 String result = objectHashMapper.fromHash(hash, String.class);
 }
+
+@Test // DATAREDIS-1179
+public void hashMapperAllowsReuseOfRedisConverter/*and thus the MappingContext holding eg. TypeAlias information*/() {
+
+WithTypeAlias source = new WithTypeAlias();
+source.value = "val";
+Map<byte[], byte[]> hash = new ObjectHashMapper().toHash(source);
+
+RedisMappingContext ctx = new RedisMappingContext();
+ctx.setInitialEntitySet(Collections.singleton(WithTypeAlias.class));
+ctx.afterPropertiesSet();
+
+MappingRedisConverter mappingRedisConverter = new MappingRedisConverter(ctx, null, null);
+mappingRedisConverter.afterPropertiesSet();
+
+ObjectHashMapper objectHashMapper = new ObjectHashMapper(mappingRedisConverter);
+assertThat(objectHashMapper.fromHash(hash)).isEqualTo(source);
+}
+
+@TypeAlias("_42_")
+@Data
+static class WithTypeAlias {
+String value;
+}
+
 }