Contents

module SlackRubyBotServer
  module Api
    module Helpers
      module CursorHelpers
        extend ActiveSupport::Concern

        # apply cursor-based pagination to a collection
        # returns a hash:
        #   results: (paginated collection subset)
        #   next: (cursor to the next page)
        def paginate_by_cursor(coll, &_block)
          fail 'Both cursor and offset parameters are present, these are mutually exclusive.' if params.key?(:offset) && params.key?(:cursor)
          results = { results: [], next: nil }
          size = (params[:size] || 10).to_i
          if params.key?(:offset)
            skip = params[:offset].to_i
            coll = coll.skip(skip)
          end
          # some items may be skipped with a block
          query = block_given? ? coll : coll.limit(size)
          query.scroll(params[:cursor]) do |record, next_cursor|
            record = yield(record) if block_given?
            results[:results] << record if record
            results[:next] = next_cursor.to_s
            break if results[:results].count >= size
          end
          results[:total_count] = coll.count if params[:total_count] && coll.respond_to?(:count)
          results
        end

        def paginate_and_sort_by_cursor(coll, options = {}, &block)
          Hashie::Mash.new(paginate_by_cursor(sort(coll, options), &block))
        end
      end
    end
  end
end

Version data entries

2 entries across 2 versions & 1 rubygems

Version	Path
slack-ruby-bot-server-0.1.1	lib/slack-ruby-bot-server/api/helpers/cursor_helpers.rb
slack-ruby-bot-server-0.1.0	lib/slack-ruby-bot-server/api/helpers/cursor_helpers.rb