debian-mirror-gitlab/lib/gitlab/pagination/offset_pagination.rb
2020-06-23 00:09:42 +05:30

106 lines
3.7 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)
paginate_with_limit_optimization(add_default_order(relation)).tap do |data|
add_pagination_headers(data)
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)
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)
header 'X-Per-Page', paginated_data.limit_value.to_s
header 'X-Page', paginated_data.current_page.to_s
header 'X-Next-Page', paginated_data.next_page.to_s
header 'X-Prev-Page', paginated_data.prev_page.to_s
header 'Link', pagination_links(paginated_data)
return if data_without_counts?(paginated_data)
header 'X-Total', paginated_data.total_count.to_s
header 'X-Total-Pages', total_pages(paginated_data).to_s
end
def pagination_links(paginated_data)
[].tap do |links|
links << %(<#{page_href(page: paginated_data.prev_page)}>; rel="prev") if paginated_data.prev_page
links << %(<#{page_href(page: paginated_data.next_page)}>; rel="next") if paginated_data.next_page
links << %(<#{page_href(page: 1)}>; rel="first")
links << %(<#{page_href(page: total_pages(paginated_data))}>; rel="last") unless data_without_counts?(paginated_data)
end.join(', ')
end
def total_pages(paginated_data)
# Ensure there is in total at least 1 page
[paginated_data.total_pages, 1].max
end
def data_without_counts?(paginated_data)
paginated_data.is_a?(Kaminari::PaginatableWithoutCount)
end
def base_request_uri
@base_request_uri ||= URI.parse(request.url).tap do |uri|
uri.host = Gitlab.config.gitlab.host
uri.port = Gitlab.config.gitlab.port
end
end
def build_page_url(query_params:)
base_request_uri.tap do |uri|
uri.query = query_params
end.to_s
end
def page_href(next_page_params = {})
query_params = params.merge(**next_page_params, per_page: per_page).to_query
build_page_url(query_params: query_params)
end
def per_page
@per_page ||= params[:per_page]
end
end
end
end