redis-om-custom-keyspace

This repository describes and demonstrates a bug in redis-om-spring library.

Description

While exploring a requirement of adding a configurable prefix to redis keys for every operation I came across fallbackKeySpaceResolver in org.springframework.data.redis.core.mapping.RedisMappingContext in spring-data.

On the surface this looked to meet the bill for our requirement. None of our redis document/hash are annotated with custom keyspace value and this would allow us to prefix everykey with configurable value. As an example if we are trying to store com.example.Company entity instead of the key being;

com.example.Company:ID1

it would be

<prefix>:Company:ID1

We fined the RedisMappingContext bean as below;

  @Bean
  @Primary
  @Profile("custom-keyspace")
  public RedisMappingContext keyValueMappingContext(
      @Value(value = "${redis.custom.keyspace.prefix}") String keyspacePrefix) {
    RedisMappingContext mappingContext = new RedisMappingContext();
    mappingContext.setFallbackKeySpaceResolver(type -> keyspacePrefix + ":" + type.getSimpleName());
    return mappingContext;
  }

This did not work as intended; and any fields marked as indexed with it's own repository method were failing the redis rearch through redis-om repository.

On further investigation identified that RediSearchIndexer is hardcoding the prefix as class.getName() + ":" in createIndexFor(Class) method. This causes all the FT.SEARCH calls to fail.

For this given example FT.CREATE looks like this;

FT.CREATE"
  "com.example.redisomcustomkeyspace.TestDataIdx" "ON" "JSON" "PREFIX" "1" "com.example.redisomcustomkeyspace.TestData:"
"SCHEMA"
  "$.number" "AS" "number" "NUMERIC"
  "$.subDataSet[0:].department" "AS" "subDataSet_department" "TAG" "SEPARATOR" "|"
  "$.subDataSet[0:].country" "AS" "subDataSet_country" "TAG" "SEPARATOR" "|"
  "$.code" "AS" "code" "TAG" "SEPARATOR" ","

instead it should look like this;

"FT.CREATE"
  "com.example.redisomcustomkeyspace.TestDataIdx" "ON" "JSON" "PREFIX" "1" "DEV:TestData:"
"SCHEMA"
  "$.number" "AS" "number" "NUMERIC"
  "$.subDataSet[0:].department" "AS" "subDataSet_department" "TAG" "SEPARATOR" "|"
  "$.subDataSet[0:].country" "AS" "subDataSet_country" "TAG" "SEPARATOR" "|"
  "$.code" "AS" "code" "TAG" "SEPARATOR" "|"

Reproduce bug

To see the working version first run the RedisOmCustomKeyspaceApplication as is and it should log this upon startup

2022-12-15 11:41:56.518  INFO 80396 --- [  restartedMain] c.e.r.RedisOmCustomKeyspaceApplication   : Started RedisOmCustomKeyspaceApplication in 25.062 seconds (JVM running for 25.825)
Optional[TestData(code=td1, number=12, values=[], subDataSet=[TestData.SubData(name=sd1, department=finance, country=uk), TestData.SubData(name=sd2, department=tech, country=usa)])]
Optional[TestData(code=td1, number=12, values=[], subDataSet=[TestData.SubData(name=sd1, department=finance, country=uk), TestData.SubData(name=sd2, department=tech, country=usa)])]
[TestData(code=td2, number=45, values=[testValue], subDataSet=[TestData.SubData(name=sd23, department=finance, country=mexico), TestData.SubData(name=sd24, department=tech, country=uk)])]
[TestData(code=td1, number=12, values=[], subDataSet=[TestData.SubData(name=sd1, department=finance, country=uk), TestData.SubData(name=sd2, department=tech, country=usa)])]

Now to reproduce the issue clear everything in redis by issuing FLUSHALL and then run the application with spring profile custom-keyspace and it would log this demonstrating the search methods fail;

2022-12-15 11:52:28.175  INFO 80695 --- [  restartedMain] c.e.r.RedisOmCustomKeyspaceApplication   : Started RedisOmCustomKeyspaceApplication in 3.558 seconds (JVM running for 4.569)
Optional[TestData(code=td1, number=12, values=[], subDataSet=[TestData.SubData(name=sd1, department=finance, country=uk), TestData.SubData(name=sd2, department=tech, country=usa)])]
Optional.empty
[]
[]

Potential fix

This fix for this bug would be to update RediSearchIndexer.createIndexFor(Class) method with this;

   String entityPrefix = cl.getName() + ":";
   if (mappingContext.hasPersistentEntityFor(cl)) {
     RedisPersistentEntity<?> persistentEntity = mappingContext.getRequiredPersistentEntity(cl);
     entityPrefix = persistentEntity.getKeySpace() != null ? persistentEntity.getKeySpace() + ":" : entityPrefix;
   }