Map collection and fields for $lookup/$graphLookup aggregation stage against domain type
#4406
Conversation
mp911de
changed the title
$lookup/$graphLookup aggregation stage against domain type
This commit enables using a type parameter to define the from collection of a lookup aggregation stage. In doing so we can derive the target collection name from the type and use the given information to also map the from field against the domain object to so that the user is able to operate on property names instead of the target db field name.
This commit enables using a type parameter to define the from collection of a graphLookup aggregation stage. In doing so we can derive the target collection name from the type and use the given information to also map the from field against the domain object to so that the user is able to operate on property names instead of the target db field name.
| * @return never {@literal null}. | ||
| * @since 4.2 | ||
| */ | ||
| default String getMappedFieldName(Class<?> type, String field) { |
There was a problem hiding this comment.
Instead of adding another method that accepts a type, how about either AggregationOperationContext.withType(…) or reusing getFields(Class<?> type)?
There was a problem hiding this comment.
A TypeBasedAggregationOperationContext can reference a type but we need to be able to map against different types not necessarily being the root that we've been starting with. Also working with getFields would do more than what we'd need.
We can see if we manage to expose more meaningful types than plain Strings so that we're able to enhance the context with additional capabilities without having to add new methods every once in a while when we reach its limits.
| @Override | ||
| public String getMappedFieldName(Class<?> type, String field) { | ||
|
|
||
| PersistentPropertyPath<MongoPersistentProperty> persistentPropertyPath = mappingContext.getPersistentPropertyPath(field, type); |
There was a problem hiding this comment.
RelaxedTypeBasedAggregationOperationContext doesn't consider any relaxed handling. Ideally, we could find an approach that embeds into our mandatory vs. relaxed field handling.
Reformatting, trailing whitespaces.
This commit enables using a type parameter to define the from collection of a
$lookup/$graphLookupaggregation stage. In doing so we can derive the target collection name from the type and use the given information to also map the from field against the domain object to so that the user is able to operate on property names instead of the target document field name.Resolves: #4379