Class: RailsAdminNext::PaginatedCollection

Inherits:
Object
  • Object
show all
Includes:
Enumerable
Defined in:
lib/rails_admin_next/support/paginated_collection.rb

Overview

View-facing adapter over a single page of records.

Wraps either a GearedPagination::Page (ActiveRecord lists, via .from_recordset) or a manually built Array (the PaperTrail audit log, whose VersionProxy objects are not an ActiveRecord::Relation) and exposes only the pagination contract the index/history views and the shared pager partial consume. Counting is lazy so the count-free "limited" pager can render prev/next without triggering a COUNT query.

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Constructor Details

#initialize(records, current_page:, per_page:, total_count:, total_pages: nil) ⇒ PaginatedCollection

total_count / total_pages may each be an Integer, nil, or a callable returning one; callables are evaluated (and memoized) lazily on first read so the count-free pager never triggers a COUNT query. total_pages defaults to a value derived from total_count (see #total_pages).



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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 29

def initialize(records, current_page:, per_page:, total_count:, total_pages: nil)
  @records = records.to_a
  @current_page = current_page.to_i
  @per_page = per_page.to_i
  @total_count = total_count
  @total_pages = total_pages
end

Instance Attribute Details

#current_page ⇒ Object (readonly)

Returns the value of attribute current_page.



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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 15

def current_page
  @current_page
end

#per_page ⇒ Object (readonly)

Returns the value of attribute per_page.



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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 15

def per_page
  @per_page
end

Class Method Details

.from_recordset(recordset, page_number, per_page) ⇒ Object 



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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 17

def self.from_recordset(recordset, page_number, per_page)
  page = recordset.page(page_number)
  new page.records,
    current_page: page.number,
    per_page:,
    total_count: -> { recordset.records_count }
end

Instance Method Details

#each ⇒ Object 



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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 37

def each(&)
  @records.each(&)
end

#first_page? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 61

def first_page?
  current_page <= 1
end

#full_page? ⇒ Boolean

This page holds a full slice, so (without a COUNT) more records may follow — drives the count-free "limited" pager's next link.

Returns:

  • (Boolean) 


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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 75

def full_page?
  size >= per_page
end

#last_page? ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 65

def last_page?
  current_page >= total_pages
end

#next_page ⇒ Object 



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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 69

def next_page
  current_page + 1 unless last_page?
end

#total_count ⇒ Object

A grouped relation makes the underlying COUNT return a Hash (one entry per group); treat its length as the count so grouped queries paginate correctly instead of letting Hash arithmetic raise.



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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 46

def total_count
  @total_count = @total_count.call if @total_count.respond_to?(:call)
  @total_count = @total_count.size if @total_count.is_a?(Hash)
  @total_count
end

#total_pages ⇒ Object

Derived from total_count when not supplied, so a grouped relation never reaches GearedPagination's Hash-unaware page_count arithmetic.



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# File 'lib/rails_admin_next/support/paginated_collection.rb', line 54

def total_pages
  @total_pages = @total_pages.call if @total_pages.respond_to?(:call)
  @total_pages = @total_pages.size if @total_pages.is_a?(Hash)
  @total_pages ||= [(total_count.to_f / per_page).ceil, 1].max
  @total_pages
end