debian-mirror-gitlab/lib/gitlab/pagination/keyset/request_context.rb
2020-10-24 23:57:45 +05:30

74 lines
1.9 KiB
Ruby

# frozen_string_literal: true
module Gitlab
module Pagination
module Keyset
class RequestContext
attr_reader :request
DEFAULT_SORT_DIRECTION = :desc
PRIMARY_KEY = :id
# A tie breaker is added as an additional order-by column
# to establish a well-defined order. We use the primary key
# column here.
TIE_BREAKER = { PRIMARY_KEY => DEFAULT_SORT_DIRECTION }.freeze
def initialize(request)
@request = request
end
# extracts Paging information from request parameters
def page
@page ||= Page.new(order_by: order_by, per_page: params[:per_page])
end
def apply_headers(next_page)
Gitlab::Pagination::Keyset::HeaderBuilder
.new(request)
.add_next_page_header(
query_params_for(next_page)
)
end
private
def order_by
return TIE_BREAKER.dup unless params[:order_by]
order_by = { params[:order_by].to_sym => params[:sort]&.to_sym || DEFAULT_SORT_DIRECTION }
# Order by an additional unique key, we use the primary key here
order_by = order_by.merge(TIE_BREAKER) unless order_by[PRIMARY_KEY]
order_by
end
def params
@params ||= request.params
end
def lower_bounds_params(page)
page.lower_bounds.each_with_object({}) do |(column, value), params|
filter = filter_with_comparator(page, column)
params[filter] = value
end
end
def filter_with_comparator(page, column)
direction = page.order_by[column]
if direction&.to_sym == :desc
"#{column}_before"
else
"#{column}_after"
end
end
def query_params_for(page)
lower_bounds_params(page)
end
end
end
end
end