Class: OccamsRecord::EagerLoaders::Base

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

Overview

Base class for eagoer loading an association. IMPORTANT eager loaders MUST remain stateless after initialization!

Direct Known Subclasses

BelongsTo, Habtm, HasOne, Through

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: :select) { ... } ⇒ Base

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.

Yields:

  • perform eager loading on this association (optional)



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# File 'lib/occams-record/eager_loaders/base.rb', line 21

def initialize(ref, scope = nil, use: nil, as: nil, optimizer: :select, &builder)
  @ref, @scope, @use, @as = ref, scope, use, as
  @model = ref.klass
  @name = (as || ref.name).to_s
  @eager_loaders = EagerLoaders::Context.new(@model)
  @optimizer = optimizer
  instance_exec(&builder) if builder
end

Instance Attribute Details

#name ⇒ String (readonly) 



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# File 'lib/occams-record/eager_loaders/base.rb', line 10

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.



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# File 'lib/occams-record/eager_loaders/base.rb', line 36

def run(rows, query_logger: nil, measurements: nil)
  query(rows) { |*args|
    assoc_rows = args[0] ? Query.new(args[0], use: @use, eager_loaders: @eager_loaders, query_logger: query_logger, measurements: measurements).run : []
    merge! assoc_rows, rows, *args[1..-1]
  }
  nil
end