debian-mirror-gitlab/lib/gitlab/graphql/connections/keyset_connection.rb
2018-12-23 12:14:25 +05:30

79 lines
1.9 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Graphql
module Connections
class KeysetConnection < GraphQL::Relay::BaseConnection
def cursor_from_node(node)
encode(node[order_field].to_s)
end
# rubocop: disable CodeReuse/ActiveRecord
def sliced_nodes
@sliced_nodes ||=
begin
sliced = nodes
sliced = sliced.where(before_slice) if before.present?
sliced = sliced.where(after_slice) if after.present?
sliced
end
end
# rubocop: enable CodeReuse/ActiveRecord
# rubocop: disable CodeReuse/ActiveRecord
def paged_nodes
if first && last
raise Gitlab::Graphql::Errors::ArgumentError.new("Can only provide either `first` or `last`, not both")
end
if last
sliced_nodes.last(limit_value)
else
sliced_nodes.limit(limit_value)
end
end
# rubocop: enable CodeReuse/ActiveRecord
private
def before_slice
if sort_direction == :asc
table[order_field].lt(decode(before))
else
table[order_field].gt(decode(before))
end
end
def after_slice
if sort_direction == :asc
table[order_field].gt(decode(after))
else
table[order_field].lt(decode(after))
end
end
def limit_value
@limit_value ||= [first, last, max_page_size].compact.min
end
def table
nodes.arel_table
end
def order_info
@order_info ||= nodes.order_values.first
end
def order_field
@order_field ||= order_info&.expr&.name || nodes.primary_key
end
def sort_direction
@order_direction ||= order_info&.direction || :desc
end
end
end
end
end