Class: OccamsRecord::EagerLoaders::PolymorphicBelongsTo

Inherits:
Object
  • Object
show all
Includes:
Builder
Defined in:
lib/occams-record/eager_loaders/polymorphic_belongs_to.rb

Overview

Eager loader for polymorphic belongs tos

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Builder

#eager_load, #eager_load_many, #eager_load_one, #nest

Constructor Details

#initialize(ref, scope = nil, use: nil, as: nil, optimizer: nil) { ... } ⇒ PolymorphicBelongsTo

ActiveRecord::Relation on which you may call all the normal query hethods (select, where, etc) as well as any scopes you’ve defined on the model.

Parameters:

  • ref (ActiveRecord::Association) —

    the ActiveRecord association

  • scope (Proc) (defaults to: nil) —

    a scope to apply to the query (optional). It will be passed an

  • use (Array<Module>) (defaults to: nil) —

    optional Module to include in the result class (single or array)

  • as (Symbol) (defaults to: nil) —

    Load the association usign a different attribute name

  • optimizer (Symbol) (defaults to: nil) —

    Only used for ‘through` associations. A no op here.

Yields:

  • perform eager loading on this association (optional)



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# File 'lib/occams-record/eager_loaders/polymorphic_belongs_to.rb', line 19

def initialize(ref, scope = nil, use: nil, as: nil, optimizer: nil, &builder)
  @ref, @scope, @use = ref, scope, use
  @name = (as || ref.name).to_s
  @foreign_type = @ref.foreign_type.to_sym
  @foreign_key = @ref.foreign_key.to_sym
  @eager_loaders = EagerLoaders::Context.new(nil, polymorphic: true)
  instance_exec(&builder) if builder
end

Instance Attribute Details

#name ⇒ String (readonly)

Returns association name.

Returns:

  • (String) —

    association name



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# File 'lib/occams-record/eager_loaders/polymorphic_belongs_to.rb', line 8

def name
  @name
end

Instance Method Details

#run(rows, query_logger: nil, measurements: nil) ⇒ Object

Run the query and merge the results into the given rows.

Parameters:

  • rows (Array<OccamsRecord::Results::Row>) —

    Array of rows used to calculate the query.

  • query_logger (Array<String>) (defaults to: nil) 


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# File 'lib/occams-record/eager_loaders/polymorphic_belongs_to.rb', line 34

def run(rows, query_logger: nil, measurements: nil)
  query(rows) { |scope|
    eager_loaders = @eager_loaders.dup
    eager_loaders.model = scope.klass
    assoc_rows = Query.new(scope, use: @use, eager_loaders: eager_loaders, query_logger: query_logger, measurements: measurements).run
    merge! assoc_rows, rows
  }
  nil
end