Module: Chewy::Query::Loading

Extended by:
ActiveSupport::Concern
Included in:
Chewy::Query
Defined in:
lib/chewy/query/loading.rb

Instance Method Summary collapse

Instance Method Details

#load(options = {}) ⇒ Object

Lazily loads actual ORM/ODM objects for search result. Returns scope marked to return loaded objects array instead of chewy wrappers. In case when object can not be loaded because it was deleted or don’t satisfy given scope or options - the result collection will contain nil value in the place of this object. Use ‘compact` method to avoid this if necessary.

UsersIndex.query(...).load #=> [#<User id: 42...>, ...]
UsersIndex.query(...).load.filter(...) #=> [#<User id: 42...>, ...]

Possible options:

<tt>:scope</tt> - used to give a scope for _every_ loaded type.

    PlacesIndex.query(...).load(scope: ->{ includes(:testimonials) })

  If places here contain cities and countries then preload will be
  done like this:

    City.where(id: [...]).includes(:testimonials)
    Country.where(id: [...]).includes(:testimonials)

  It is also possible to pass own scope for every loaded type:

    PlacesIndex.query(...).load(
      city: { scope: ->{ includes(:testimonials, :country) }}
      country: { scope: ->{ includes(:testimonials, :cities) }}
    )

  And loading will be performed as:

    City.where(id: [...]).includes(:testimonials, :country)
    Country.where(id: [...]).includes(:testimonials, :cities)

  In case of ActiveRecord objects loading the same result
  will be reached using ActiveRecord scopes instead of
  lambdas. But it works only with per-type scopes,
  and doesn't work with the common scope.

    PlacesIndex.query(...).load(
      city: { scope: City.includes(:testimonials, :country) }
      country: { scope: Country.includes(:testimonials, :cities) }
    )

<tt>:only</tt> - loads objects for the specified types

  PlacesIndex.query(...).load(only: :city)
  PlacesIndex.query(...).load(only: [:city])
  PlacesIndex.query(...).load(only: [:city, :country])

<tt>:except</tt> - doesn't load listed types

  PlacesIndex.query(...).load(except: :city)
  PlacesIndex.query(...).load(except: [:city])
  PlacesIndex.query(...).load(except: [:city, :country])



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# File 'lib/chewy/query/loading.rb', line 62

def load(options = {})
  chain { criteria.update_options preload: options, loaded_objects: true }
end

#preload(options = {}) ⇒ Object

This methods is just convenient way to preload some ORM/ODM objects and continue to work with Chewy wrappers. Returns Chewy query scope. Note that ‘load` method performs ES request so preload method should also be the last in scope methods chain. Takes the same options as the `load` method

PlacesIndex.query(...).preload(only: :city)

Loaded objects are also attached to corresponding Chewy type wrapper objects and available with ‘_object` accessor.

scope = PlacesIndex.query(...)
preload_scope = scope.preload
preload_scope.first #=> PlacesIndex::City wrapper instance
preload_scope.first._object #=> City model instance
scope.load == preload_scope.map(&:_object) #=> true



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# File 'lib/chewy/query/loading.rb', line 83

def preload(options = {})
  chain { criteria.update_options preload: options, loaded_objects: false }
end