Using className as type hint field name with versioned entities fails with InvalidPersistentPropertyPath in UpdateMapper [DATAMONGO-2168]

[spring-projects-issues]

Mark Paluch opened DATAMONGO-2168 and commented

Using className as type hint field name fails in in the UpdateMapper and a nested PropertyPath resolution with

InvalidPersistentPropertyPath: No property 'class' found on class org.springframework.data.mongodb.core.Foo$MyEntity!

Ideally, UpdateMapper and QueryMapper ignore type hint fields during mapping as this also prevents PropertyReferenceException that happens in MetadataBackedField.getPath (that's why _class works).

The problem was originally reported through Gitter in the context of migrating from Morphia to Spring Data MongoDB as Morphia uses className to store type hints.

Full stack trace:

org.springframework.data.mapping.context.InvalidPersistentPropertyPath: No property 'class' found on class org.springframework.data.mongodb.core.Foo$MyEntity! Did you mean: ?

	at org.springframework.data.mapping.context.PersistentPropertyPathFactory.createPersistentPropertyPath(PersistentPropertyPathFactory.java:215)
	at org.springframework.data.mapping.context.PersistentPropertyPathFactory.lambda$getPersistentPropertyPath$2(PersistentPropertyPathFactory.java:182)
	at java.util.concurrent.ConcurrentMap.computeIfAbsent(ConcurrentMap.java:324)
	at org.springframework.data.mapping.context.PersistentPropertyPathFactory.getPersistentPropertyPath(PersistentPropertyPathFactory.java:181)
	at org.springframework.data.mapping.context.PersistentPropertyPathFactory.from(PersistentPropertyPathFactory.java:96)
	at org.springframework.data.mapping.context.PersistentPropertyPathFactory.from(PersistentPropertyPathFactory.java:109)
	at org.springframework.data.mapping.context.AbstractMappingContext.getPersistentPropertyPath(AbstractMappingContext.java:275)
	at org.springframework.data.mongodb.core.convert.QueryMapper$MetadataBackedField.getPath(QueryMapper.java:990)
	at org.springframework.data.mongodb.core.convert.QueryMapper$MetadataBackedField.<init>(QueryMapper.java:873)
	at org.springframework.data.mongodb.core.convert.QueryMapper$MetadataBackedField.<init>(QueryMapper.java:850)
	at org.springframework.data.mongodb.core.convert.UpdateMapper$MetadataBackedUpdateField.<init>(UpdateMapper.java:289)
	at org.springframework.data.mongodb.core.convert.UpdateMapper.createPropertyField(UpdateMapper.java:249)
	at org.springframework.data.mongodb.core.convert.QueryMapper.getMappedObject(QueryMapper.java:142)
	at org.springframework.data.mongodb.core.convert.UpdateMapper.getMappedObject(UpdateMapper.java:67)
	at org.springframework.data.mongodb.core.MongoTemplate$8.doInCollection(MongoTemplate.java:1582)
	at org.springframework.data.mongodb.core.MongoTemplate$8.doInCollection(MongoTemplate.java:1563)
	at org.springframework.data.mongodb.core.MongoTemplate.execute(MongoTemplate.java:536)
	at org.springframework.data.mongodb.core.MongoTemplate.doUpdate(MongoTemplate.java:1563)
	at org.springframework.data.mongodb.core.MongoTemplate.doSaveVersioned(MongoTemplate.java:1388)
	at org.springframework.data.mongodb.core.MongoTemplate.save(MongoTemplate.java:1361)
	at org.springframework.data.mongodb.core.MongoTemplate.save(MongoTemplate.java:1348)

public class Reproducer {

	@Test
	public void reproducer() {

		MongoMappingContext context = new MongoMappingContext();

		MappingMongoConverter converter = new MappingMongoConverter(NoOpDbRefResolver.INSTANCE, context);
		converter.setTypeMapper(new DefaultMongoTypeMapper("className"));

		MongoTemplate template = new MongoTemplate(new SimpleMongoClientDbFactory("mongodb://localhost/test"), converter);

		List<MyEntity> all = template.findAll(MyEntity.class);
		MyEntity entity = all.get(0);
		entity.setName("foo");

		template.save(entity);
	}

	@Data
	static class MyEntity {

		ObjectId id;

		@Version long version;

		String name;
	}
}

---

Affects: 2.0.12 (Kay SR12)

Reference URL: https://gitter.im/spring-projects/spring-data?at=5c1258bb33d9e11991c743bd

Issue Links:

• DATAMONGO-2174 InvalidPersistentPropertyPath with @Version

Referenced from: pull request #631

Backported to: 2.1.10 (Lovelace SR10)

[spring-projects-issues]

Mark Paluch commented

There are two issues here:

1. QueryMapper attempts to map type hints. Mapping of _class fails at an earlier stage and that's why we don't see issues when using the default type key.
2. MongoTemplate.doSaveVersioned(…) creates a mapped Update and doUpdate(…) runs another mapping pass on it. Looking on the other users of doUpdate(…), only doSaveVersioned(…) uses an already mapped object, the other update methods use an unmapped Update object