lib/jsonapi/paginator.rb in jsonapi-resources-0.4.0 vs lib/jsonapi/paginator.rb in jsonapi-resources-0.4.1

@@ -5,29 +5,88 @@
 
     def apply(relation, order_options)
       # relation
     end
 
+    def links_page_params(options = {})
+      # :nocov:
+      {}
+      # :nocov:
+    end
+
     class << self
+      def requires_record_count
+        # :nocov:
+        false
+        # :nocov:
+      end
+
       def paginator_for(paginator)
         paginator_class_name = "#{paginator.to_s.camelize}Paginator"
         paginator_class_name.safe_constantize if paginator_class_name
       end
     end
   end
 end
 
 class OffsetPaginator < JSONAPI::Paginator
+  attr_reader :limit, :offset
+
   def initialize(params)
     parse_pagination_params(params)
     verify_pagination_params
   end
 
+  def self.requires_record_count
+    true
+  end
+
   def apply(relation, order_options)
     relation.offset(@offset).limit(@limit)
   end
 
+  def links_page_params(options = {})
+    record_count = options[:record_count]
+    links_page_params = {}
+
+    links_page_params['first'] = {
+      'offset' => 0,
+      'limit' => @limit
+    }
+
+    if @offset > 0
+      previous_offset = @offset - @limit
+
+      if previous_offset < 0
+        previous_offset = 0
+      end
+
+      links_page_params['previous'] = {
+        'offset' => previous_offset,
+        'limit' => @limit
+      }
+    end
+
+    next_offset = @offset + @limit
+
+    unless next_offset >= record_count
+      links_page_params['next'] = {
+        'offset' => next_offset,
+        'limit'=> @limit
+      }
+    end
+
+    if record_count
+      links_page_params['last'] = {
+        'offset' => record_count - @limit,
+        'limit' => @limit
+      }
+    end
+
+    links_page_params
+  end
+
   private
   def parse_pagination_params(params)
     if params.nil?
       @offset = 0
       @limit = JSONAPI.configuration.default_page_size
@@ -56,17 +115,58 @@
     end
   end
 end
 
 class PagedPaginator < JSONAPI::Paginator
+  attr_reader :size, :number
+
   def initialize(params)
     parse_pagination_params(params)
     verify_pagination_params
   end
 
+  def self.requires_record_count
+    true
+  end
+
   def apply(relation, order_options)
     offset = (@number - 1) * @size
     relation.offset(offset).limit(@size)
+  end
+
+  def links_page_params(options = {})
+    record_count = options[:record_count]
+    page_count = (record_count / @size.to_f).ceil
+
+    links_page_params = {}
+
+    links_page_params['first'] = {
+      'number' => 1,
+      'size' => @size
+    }
+
+    if @number > 1
+      links_page_params['previous'] = {
+        'number' => @number - 1,
+        'size' => @size
+      }
+    end
+
+    unless @number >= page_count
+      links_page_params['next'] = {
+        'number' => @number + 1,
+        'size'=> @size
+      }
+    end
+
+    if record_count
+      links_page_params['last'] = {
+        'number' => page_count,
+        'size' => @size
+      }
+    end
+
+    links_page_params
   end
 
   private
   def parse_pagination_params(params)
     if params.nil?