Method: GraphQL::Schema::Field#resolve

Defined in:

lib/graphql/schema/field.rb

#resolve(object, args, query_ctx) ⇒ Object

This method is called by the interpreter for each field. You can extend it in your base field classes.

Parameters:

• object (GraphQL::Schema::Object) —

  An instance of some type class, wrapping an application object

• args (Hash) —

  A symbol-keyed hash of Ruby keyword arguments. (Empty if no args)

• ctx (GraphQL::Query::Context)

# File 'lib/graphql/schema/field.rb', line 722

def resolve(object, args, query_ctx)
  # Unwrap the GraphQL object to get the application object.
  application_object = object.object
  method_receiver = nil
  method_to_call = nil
  method_args = nil

  @own_validators && Schema::Validator.validate!(validators, application_object, query_ctx, args)

  query_ctx.query.after_lazy(self.authorized?(application_object, args, query_ctx)) do |is_authorized|
    if is_authorized
      with_extensions(object, args, query_ctx) do |obj, ruby_kwargs|
        method_args = ruby_kwargs
        if @resolver_class
          if obj.is_a?(GraphQL::Schema::Object)
            obj = obj.object
          end
          obj = @resolver_class.new(object: obj, context: query_ctx, field: self)
        end

        inner_object = obj.object

        if !NOT_CONFIGURED.equal?(@hash_key)
          hash_value = if inner_object.is_a?(Hash)
            inner_object.key?(@hash_key) ? inner_object[@hash_key] : inner_object[@hash_key_str]
          elsif inner_object.respond_to?(:[])
            inner_object[@hash_key]
          else
            nil
          end
          if hash_value == false
            hash_value
          else
            hash_value || (@fallback_value != NOT_CONFIGURED ? @fallback_value : nil)
          end
        elsif obj.respond_to?(resolver_method)
          method_to_call = resolver_method
          method_receiver = obj
          # Call the method with kwargs, if there are any
          if !ruby_kwargs.empty?
            obj.public_send(resolver_method, **ruby_kwargs)
          else
            obj.public_send(resolver_method)
          end
        elsif inner_object.is_a?(Hash)
          if @dig_keys
            inner_object.dig(*@dig_keys)
          elsif inner_object.key?(@method_sym)
            inner_object[@method_sym]
          elsif inner_object.key?(@method_str) || !inner_object.default_proc.nil?
            inner_object[@method_str]
          elsif @fallback_value != NOT_CONFIGURED
            @fallback_value
          else
            nil
          end
        elsif inner_object.respond_to?(@method_sym)
          method_to_call = @method_sym
          method_receiver = obj.object
          if !ruby_kwargs.empty?
            inner_object.public_send(@method_sym, **ruby_kwargs)
          else
            inner_object.public_send(@method_sym)
          end
        elsif @fallback_value != NOT_CONFIGURED
          @fallback_value
        else
          raise <<-ERR
        Failed to implement #{@owner.graphql_name}.#{@name}, tried:

        - `#{obj.class}##{resolver_method}`, which did not exist
        - `#{inner_object.class}##{@method_sym}`, which did not exist
        - Looking up hash key `#{@method_sym.inspect}` or `#{@method_str.inspect}` on `#{inner_object}`, but it wasn't a Hash

        To implement this field, define one of the methods above (and check for typos), or supply a `fallback_value`.
        ERR
        end
      end
    else
      raise GraphQL::UnauthorizedFieldError.new(object: application_object, type: object.class, context: query_ctx, field: self)
    end
  end
rescue GraphQL::UnauthorizedFieldError => err
  err.field ||= self
  begin
    query_ctx.schema.unauthorized_field(err)
  rescue GraphQL::ExecutionError => err
    err
  end
rescue GraphQL::UnauthorizedError => err
  begin
    query_ctx.schema.unauthorized_object(err)
  rescue GraphQL::ExecutionError => err
    err
  end
rescue ArgumentError
  if method_receiver && method_to_call
    assert_satisfactory_implementation(method_receiver, method_to_call, method_args)
  end
  # if the line above doesn't raise, re-raise
  raise
rescue GraphQL::ExecutionError => err
  err
end