Good afternoon everyone.

Im using the gem Paperclip in order to upload the images of the users to
server. But I having problems with it. I don’t know how to resize the
size after uploading the image.

I’m using CSS to try to change the size but is not working. I think
Paperclip is showing the exactly size that it was saved. Could anyone

Another question is about the location of the pictures that the gem
Paperclip is using. When I add a picture with this gem, Where it is

Thank you & best regards.


Good morning Alfredo :wink:

file sizes:

Paperclip will post process (resize) your images - if all validations
are ok - otherwise post processing will not commence.

Paperclip supports an extensible selection of post-processors. When you
define a set of styles for an attachment, by default it is expected that
those “styles” are actually “thumbnails”. However, you can do much more
than just thumbnail images. By defining a subclass of
Paperclip::Processor, you can perform any processing you want on the
files that are attached.

eg.: has_attached_file :avatar, :styles => { :medium => “300x300>”,
:thumb => “100x100>” }

this image will have two resized copies, a medium and a thumb
which you may show using a helper:

<%= image_tag @user.avatar.url(:medium) %>

location of file:

(from - understanding storage):
The files that are assigned as attachments are, by default, placed in
the directory specified by the :path option to has_attached_file. By
default, this location is


Den 05/04/2014 kl. 08.55 skrev Alfredo B. [email protected]:

Hi Alfredo,
both your questions are answered in the README of the github project:

The sizes can be choosed with the :styles param of the
method (in the model):

has_attached_file :avatar, :styles => { :medium => “300x300>”, :thumb =>
“100x100>” }

In your view you can select the style to show:

<%= image_tag @user.avatar.url(:medium) %>

The files are saved in public/system. Read the “Storage” paragraph of
README for a better comprehension

Remember, when using CSS to show different sizes of an image, that the
image is downloaded in the original size: if you show an image 200x200
(using css) but the image is 2000x2000 (1 or 2 MB) you download the full
image, which is a very slow solution! :slight_smile:
Use CSS only for minimal changes of size.


2014-04-05 8:55 GMT+02:00 Alfredo B. [email protected]:

Hi there,

I’ve been problems using this line: “<%= image_tag
@user.avatar.url(:medium) %>”

When I use that line, in the browser I just can see text instead of the
picture. And RubyMine does not recognize “avatar”. If I use this line
browser shows the picture but I cant resize the picture.

*<%= image_tag @user.avatar_file_name %>*Any idea?.

Thank you.


El sábado, 5 de abril de 2014 14:55:59 UTC+8, Alfredo B. escribió:

On Apr 5, 2014, at 7:46 AM, Alfredo B. wrote:

Is your attachment called avatar? Or is it called something else, like
picture? In the example code, they are presuming that your attachment is
called avatar, and everything proceeds from that point.


Thank both of you for the answer. I’m going to try it now. I’ll update
with the results.

Thank you & Best regards.


El sábado, 5 de abril de 2014 14:55:59 UTC+8, Alfredo B. escribió:

Any idea of the issues?.

Thanks a lot.


I’m not 100% sure but I think is called “avatar”. Below is the table of
users that is in the database.

 id = 1
           name = alf
password_digest =

photo = alf
created_at = 2014-04-07 12:54:07.328582
updated_at = 2014-04-07 12:54:07.328582
avatar_file_name = alf.jpg
avatar_content_type = image/jpeg
avatar_file_size = 12425
avatar_updated_at = 2014-04-07 12:54:07.173774

Could you check if is good configured?.

I’m also having a new error. When I try to print all the pictures that
user has with the following line, Ruby does not recognize the data.

users/show.html.erb => <% @photos.each do |product| %>
users_controller.rb => @photos = Photo.order(:title)

Could you please check why I can’t acces to the data of Photos?. The
browser give me this error =>

undefined method `each’ for nil:NilClass

Thank you and sorry for the long text :frowning:


El sábado, 5 de abril de 2014 14:55:59 UTC+8, Alfredo B. escribió:

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