Class: GraphQL::Query::FieldResolutionStrategy

Inherits:
Object
  • Object
show all
Defined in:
lib/graph_ql/query/field_resolution_strategy.rb

Defined Under Namespace

Classes: EnumResolutionStrategy, ListResolutionStrategy, NonNullResolutionStrategy, ObjectResolutionStrategy, ScalarResolutionStrategy

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(ast_field, parent_type, target, operation_resolver) ⇒ FieldResolutionStrategy

Returns a new instance of FieldResolutionStrategy.



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# File 'lib/graph_ql/query/field_resolution_strategy.rb', line 4

def initialize(ast_field, parent_type, target, operation_resolver)
  field_name = ast_field.name
  field = operation_resolver.query.schema.get_field(parent_type, field_name) || raise("No field found on #{parent_type.name} '#{parent_type}' for '#{field_name}'")
  arguments = GraphQL::Query::Arguments.new(ast_field.arguments, field.arguments, operation_resolver.variables)
  value = field.resolve(target, arguments, operation_resolver.context)
  if value.nil?
    @result_value = value
  else
    if value == GraphQL::Query::DEFAULT_RESOLVE
      begin
        value = target.send(field_name)
      rescue NoMethodError => err
        raise("Couldn't resolve field '#{field_name}' to #{target.class} '#{target}' (resulted in #{err})")
      end
    end
    resolved_type = field.type.kind.resolve(field.type, value)
    strategy_class = self.class.get_strategy_for_kind(resolved_type.kind)
    result_strategy = strategy_class.new(value, resolved_type, target, parent_type, ast_field, operation_resolver)
    @result_value = result_strategy.result
  end
  result_name = ast_field.alias || ast_field.name
  @result = { result_name => @result_value}
end

Instance Attribute Details

#result ⇒ Object (readonly)

Returns the value of attribute result.



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# File 'lib/graph_ql/query/field_resolution_strategy.rb', line 2

def result
  @result
end

#result_value ⇒ Object (readonly)

Returns the value of attribute result_value.



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# File 'lib/graph_ql/query/field_resolution_strategy.rb', line 2

def result_value
  @result_value
end

Class Method Details

.get_strategy_for_kind(kind) ⇒ Object 



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# File 'lib/graph_ql/query/field_resolution_strategy.rb', line 28

def self.get_strategy_for_kind(kind)
  FIELD_TYPE_KIND_STRATEGIES[kind] || raise("No strategy for #{kind}")
end