Why does Doctrine impose artificial limits on repository method names?

Question

Can someone please explain to me why Doctrine requires repository method names to start with findBy, findOneBy, or countBy and why even names with those prefixes must end with a column name?

There are valid use cases where it is useful, for example, to count the number of records that contain several matching columns.

// src/Repository/FreeClassQueryRepository.php
class FreeClassQueryRepository extends ServiceEntityRepository
{
  .
  .
  .
  /**
   * Returns true if one or more free class query records match the supplied
   * FreeClassQuery object.
   *
   * @param   FreeClassQuery $query
   * @return  bool
   * @throws  \Doctrine\ORM\NonUniqueResultException
   */
  public function checkForDuplicate( FreeClassQuery $query )
  {
    $q = $this->createQueryBuilder( 'fcq' )
              ->select( 'COUNT(id)' )
              ->andWhere( 'fcq.name = :name' )
              ->setParameter( 'name', $query->getName())
              ->andWhere( 'fcq.email = :email' )
              ->setParameter( 'email', $query->getEmail())
              ->andWhere( 'fcq.street = :street' )
              ->setParameter( 'street', $query->getStreet())
              ->andWhere( 'fcq.city = :city' )
              ->setParameter( 'city', $query->getCity())
              ->andWhere( 'fcq.state = :state' )
              ->setParameter( 'state', $query->getState());
    return $q->getQuery()->getSingleScalarResult();

  }
  .
  .
  .
}

Calling this method results in this error:

[ERROR] app:debug (Prototyping...) failed Undefined method 'checkForDuplicate'. The method name must start with either findBy, findOneBy or countBy!

Could you cite something or share some code? I have functions in Doctrine repositories that do not start with find or count. — ficuscr
@ficusr, Sure. Please see the edit to my original post. Thanks. — David Patterson
OK. So that looks to be magic sauce. The exception is raised in __call - if calling a concrete method of the class that should not happen. So, has more to do with how it's invoked. How do you use checkForDupelicate? — ficuscr
The method name must start with either findBy or findOneBy. Undefined method Symfony? might be helpful. — ficuscr

David Patterson David Patterson · Accepted Answer · 2019-07-04T15:09:38

This was happening because the @ORM\Entity annotation in the entity class was missing the repositoryClass="App\Repository\FreeClassQueryRepository" attribute.

Thanks to @ficuscr for the link to a similar StackOverflow question (see his third comment).

Why does Doctrine impose artificial limits on repository method names?

1 Answers