Use QueryDSL Path expressions to specify field constraints on repository queries [DATAMONGO-103]

[spring-projects-issues]

Mark Pollack opened DATAMONGO-103 and commented

Instead of

public interface PersonRepository extends MongoRepository<Person, String>

  @Query(value="{ 'firstname' : ?0 }", fields="{'firstname' : 1, 'lastname' : 1")
  List<Person> findByThePersonsFirstname(String firstname);
}

if we had

public interface PersonRepository extends MongoRepository<Person, String>

  @Query(value="{ 'firstname' : ?0 }",
  List<Person> findByThePersonsFirstname(String firstname, Path<Person>... paths);
}

or more generally

public interface PersonRepository extends MongoRepository<Person, String>
 
  List<Person> findByFirstname(String firstname, Path<Person>... paths);
}

would like to invoke like this

List<Person> folks = repo.findByFirstname(String firstname, QPerson.firstName, QPerson.lastName);

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Affects: 1.0 M2

1 votes, 1 watchers

[spring-projects-issues]

Timo Westkämper commented

Good idea. Though the type parameter of Path refers to the type of the last path element, not the parent. Your example should be

List<Person> findByFirstname(String firstname, Path<String>... paths);

Unfortunately with Querydsl it is not possible to constrain the paths to Person children, since they can be deeper, e.g.

List<Person> folks = repo.findByFirstname(String firstname, QPerson.person.department.name;