debian-mirror-gitlab/lib/gitlab/pagination/offset_pagination.rb
2021-02-22 17:27:13 +05:30

74 lines
2.8 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Pagination
class OffsetPagination < Base
attr_reader :request_context
delegate :params, :header, :request, to: :request_context
def initialize(request_context)
@request_context = request_context
end
def paginate(relation, exclude_total_headers: false)
paginate_with_limit_optimization(add_default_order(relation)).tap do |data|
add_pagination_headers(data, exclude_total_headers)
end
end
private
def paginate_with_limit_optimization(relation)
# do not paginate relation if it is already paginated
pagination_data = if relation.respond_to?(:current_page) && relation.current_page == params[:page] && relation.limit_value == params[:per_page]
relation
else
relation.page(params[:page]).per(params[:per_page])
end
return pagination_data unless pagination_data.is_a?(ActiveRecord::Relation)
return pagination_data unless Feature.enabled?(:api_kaminari_count_with_limit, type: :ops)
limited_total_count = pagination_data.total_count_with_limit
if limited_total_count > Kaminari::ActiveRecordRelationMethods::MAX_COUNT_LIMIT
# The call to `total_count_with_limit` memoizes `@arel` because of a call to `references_eager_loaded_tables?`
# We need to call `reset` because `without_count` relies on `@arel` being unmemoized
pagination_data.reset.without_count
else
pagination_data
end
end
def add_default_order(relation)
if relation.is_a?(ActiveRecord::Relation) && relation.order_values.empty?
relation = relation.order(:id) # rubocop: disable CodeReuse/ActiveRecord
end
relation
end
def add_pagination_headers(paginated_data, exclude_total_headers)
Gitlab::Pagination::OffsetHeaderBuilder.new(
request_context: self, per_page: paginated_data.limit_value, page: paginated_data.current_page,
next_page: paginated_data.next_page, prev_page: paginated_data.prev_page,
total: total_count(paginated_data), total_pages: total_pages(paginated_data)
).execute(exclude_total_headers: exclude_total_headers, data_without_counts: data_without_counts?(paginated_data))
end
def data_without_counts?(paginated_data)
paginated_data.is_a?(Kaminari::PaginatableWithoutCount)
end
def total_count(paginated_data)
paginated_data.total_count unless data_without_counts?(paginated_data)
end
def total_pages(paginated_data)
return if data_without_counts?(paginated_data)
# Ensure there is in total at least 1 page
[paginated_data.total_pages, 1].max
end
end
end
end