Projection

The official MongoDB Scala driver supports projection using the Projections helper. One can still use that approach if desired.

However, scala-bson-query defines projection support which allows:

  // Using untyped.projection
  {
  import io.github.osxhacker.query.mongodb.untyped.projection._
  import shapeless._

  val result = collection.find ().projection (
    returning {
        available =>
          available.a ::
          availalble.b ::
          HNil
      }
    )
  }

  // Using typed.projection
  {
  import io.github.osxhacker.query.mongodb.typed.projection._

  case class Nested (rating : Double)
  case class ExampleDocument (aProperty : String, another : Int, nested : Nested)

  val result = collection.find ().projection (into[ExampleDocument] ())
  }

Methods

Typed

For the purposes of the method API reference, assume the following code is in scope:

import io.github.osxhacker.query.projection.typed._

• into, a method which inspects the parameterized case class type, producing a projection containing all discoverable properties.

Untyped

For the purposes of the method API reference, assume the following code is in scope:

import io.github.osxhacker.query.projection.untyped._

• returning, method which allows for the production of an HList having each property to return explicitly specified.