Module: NextPage::PaginationAttributes

Defined in:
lib/next_page/pagination_attributes.rb

Overview

Pagination Attributes

Module PaginationAttributes adds in methods required for pagination links: previous_page, current_page, next_page, and total_pages. It reads the offset and limit on the query to determine the values.

In some cases the query will not support count. In that case, there are two ways to override the default behavior:

  • provide a count_query that can resolve the attributes

  • specify the following attributes manually: current_page, total_count, and per_page

Instance Attribute Summary collapse

Instance Method Summary collapse

Instance Attribute Details

#count_query ⇒ Object

checks first to see if an override query has been provided, then fails back to self



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# File 'lib/next_page/pagination_attributes.rb', line 40

def count_query
  @count_query || self
end

#current_page ⇒ Object 



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# File 'lib/next_page/pagination_attributes.rb', line 19

def current_page
  @current_page ||= (count_query.offset_value || 0) + 1
end

#per_page ⇒ Object 



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# File 'lib/next_page/pagination_attributes.rb', line 35

def per_page
  @per_page ||= count_query.limit_value
end

#total_count ⇒ Object 



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# File 'lib/next_page/pagination_attributes.rb', line 27

def total_count
  @total_count ||= count_query.unscope(:limit).unscope(:offset).count
end

Instance Method Details

#next_page ⇒ Object 



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# File 'lib/next_page/pagination_attributes.rb', line 23

def next_page
  total_pages > current_page ? current_page + 1 : nil
end

#previous_page ⇒ Object 



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# File 'lib/next_page/pagination_attributes.rb', line 15

def previous_page
  current_page > 1 ? current_page - 1 : nil
end

#total_pages ⇒ Object 



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# File 'lib/next_page/pagination_attributes.rb', line 31

def total_pages
  total_count.fdiv(per_page).ceil
end