add pagination to the page

controller/post.rb

@@ -6,8 +6,15 @@ module Routes
     end
 
     def self.define_posts(session)
-      page     = (session.request.params['page'] || 0).to_i
-      per_page = (session.request.params['per_page'] || 10).to_i
+      # compute pages
+      page = session.request.params['page'].to_i
+      session.options[:page] = page if page
+      per_page = session.request.params['per_page'].to_i
+      per_page = 10 if per_page == 0
+      session.options[:per_page] = per_page if per_page
+      session.options[:pages] = DB[:posts].filter(:released => true).count / per_page
+
+      # fetch the posts to show
       posts = DB[:posts].
         filter(:released => true).
         select(:posts__id___post_id, :written, :title, :content, :username).

templates/posts/index.html.slim

@@ -1,3 +1,8 @@
+- if 0 < fetch(:page)
+  a.page.up(
+    href="/post?page=#{fetch(:page) - 1}&per_page=#{fetch(:per_page)}"
+    ) show newer
+
 - for post in fetch(:posts)
   article
     header
@@ -8,3 +13,8 @@
       .date=  post[:written].strftime('%Y-%m-%d')
       .time=  post[:written].strftime('%H-%M')
     section==Kramdown::Document.new(post[:content]).to_html
+
+- if fetch(:page) < fetch(:pages)
+  a.page.down(
+    href="/post?page=#{fetch(:page) + 1}&per_page=#{fetch(:per_page)}"
+    ) show older