Generating an archive of blog posts from list of posts in Ruby

Question

I'm creating a blog using Ruby on Rails for my site. I really like the way some blogging platforms have an archive of all the posts on the blog as seen here

I'm trying to write code to generate that in Ruby. I have a rough idea as seen by my code

<h6>Archive</h6>
<%
    @posts.each do |post|
        #Add dropdown for post year if first entry into year
        #Add dropdown for post month if first entry into month
        #Add post to dropdown of month under dropdown of year
    end
%>

However, I'm having a hard time translating that into ERB code as I'm still fairly new to Ruby. Can someone give me an example of this being done? Thanks!

EDIT: The list @posts is sorted newest to oldest

Answer 1

You can use Ruby's group_by method. That will allow you put them into buckets using the created_at field.

Edit: This rails cast explains it very well: http://railscasts.com/episodes/29-group-by-month?view=asciicast