Strange error uploading file

Hello, I’m just starting to learn ruby on rails and I have a problem
uploading pictures to my server.

I just want to store the url of the picture and upload its file to
public/images when I create a new Picture record. I don’t know where is
my error and I am going crazy. I don’t need it for any customer or
similar, I only want to understand why it doesn’t work. Please help!

I have used this tutorial:
http://programming-ut.blogspot.com/2010/01/ruby-on-rails-file-upload.html

I have two tables:

Dog

  • name
  • weight

Picture

  • url
  • dog_id

Dog has many Picture
Picture belong to Dog

In picture_controller I just call a method ‘upload’ of the model at
creation:

def create
@picture = Picture.new(params[:picture])
post = Picture.upload(params[:picture],@picture)
respond_to do |format|
if @picture.save
format.html { redirect_to(@picture, :notice => ‘Created!’) }
format.xml { render :xml => @picture, :status => :created,
:location => @picture }
else
format.html { render :action => “new” }
format.xml { render :xml => @picture.errors, :status =>
:unprocessable_entity }
end
end
end

The method code is:

class Picture < ActiveRecord::Base
belongs_to :dog
def self.upload(data,insert)
fullname = data[‘url’].original_filename
name = File.basename(fullname)
name.sub(/[^\w.-]/,‘_’)
insert.url = name
directory = “/public/images”
path = File.join(directory, insert.url)
File.open(path, “wb”) { |f| f.write(data[‘url’].read) }
end
end

And the view:

New picture

<% form_for(@picture, :html => {:multipart => true}) do |f| %> <%= f.error_messages %>

<%= f.label :url %>
<%= f.file_field :url %>

<%= f.label :perro_id %>
<%= f.text_field :perro_id %>

<%= f.submit 'Create' %>

<% end %> When I push button Create, the log shows:

Processing PicturesController#create (for 83.44.0.216 at 2010-12-11
21:16:49) [POST]
Parameters: {“commit”=>“Create”,
“authenticity_token”=>“oZTzcJa99hTRHHl9hGSTEG70cbLITHt58wkNZIMlFo4=”,
“picture”=>“perro_id”=>“”,
“url”=>#<File:/tmp/RackMultipart20101211-28729-1ev718o-0>}}

Errno::ENOENT (No such file or directory - /public/prueba):
app/models/picture.rb:26:in initialize' app/models/picture.rb:26:in open’

If you have read to this point… I can only say thanks!