I really like will_paginate for Ruby on Rails because it's easy to setup and the intent of pagination is communicated well.
The only thing that bothers me is that it can be used with ActiveRecord only. My blog runs on Rails without ActiveRecord and all posts are kept in a git repository as simple markdown files. So I needed to write a wrapper that returns a WillPaginate::Collection and
works on Arrays.
I came up with this:
# encoding: utf-8
require 'will_paginate'
require 'will_paginate/collection'
module WillPaginateArrays
def paginate params
params[:per_page] ||= 5
params[:page] ||= 1
return ::WillPaginate::Collection.create(
params.fetch(:page),
params.fetch(:per_page),
self.length) do |pager|
first_index = (pager.current_page - 1) * pager.per_page
last_index = pager.current_page * pager.per_page
pager.replace self[first_index...last_index]
end
end
end
The test_unit tests for the above snippet looks like this:
# encoding: utf-8
require 'will_paginate_arrays'
require 'test_helper'
class WillPaginateArraysTest < ActiveSupport::TestCase
test "usage" do
array = Array.new
array.extend WillPaginateArrays
assert array.respond_to?(:paginate)
end
test "#paginate follows per_page option" do
array = (1..10).to_a
array.extend WillPaginateArrays
assert_equal 2, array.paginate(per_page: 2).length
assert_equal [1, 2], array.paginate(per_page: 2)
end
test "#paginate follows page option" do
array = (1..10).to_a
array.extend WillPaginateArrays
assert_equal (6..10).to_a, array.paginate(page: 2)
end
test "#paginate has total_pages" do
array = (1..10).to_a
array.extend WillPaginateArrays
assert_equal 3, array.paginate(per_page: 4).total_pages
end
test "#paginate handles last page correctly" do
array = (1..10).to_a
array.extend WillPaginateArrays
assert_equal [9, 10], array.paginate(per_page: 4, page: 3)
end
end
As you can see usage is fairly easy:
- create a new array.
- extend the array with the
WillPaginateArrays module
- call
#paginate just like you normally would and use the will_paginate helper in your views.
Done!
