UK Ruby on Rails, Exalead, AWS, Consultancy - Blog Comments

Comment on 'Revisited: roll your own pagination links with will_paginate and Rails 3' by Rob Anderton

2011-05-26T10:30:05Z

@yoshyosh: I'm not sure you really need the extra file, you just need to make sure you follow Rails naming conventions for the source file. So it's lib/pagination_list_link_renderer.rb not paginationlistlinkrenderer.rb as without the underscores the autoloader won't work.

As for the images, you could override the previous_page and next_page methods in your renderer and do something like I showed in this earlier comment.

@Gourav: an alternative approach would be to override to_html in the renderer and conditionally add the previous/next links based on the current page:

class PaginationLinkRenderer < WillPaginate::LinkRenderer

  def to_html
    links = @options[:page_links] ? windowed_links : []

    links.unshift(page_link_or_span(@collection.previous_page, 'previous', @options[:previous_label])) unless @collection.current_page == 1
    links.push(page_link_or_span(@collection.next_page, 'next', @options[:next_label])) unless @collection.current_page == @collection.total_pages

    html = links.join(@options[:separator])
    @options[:container] ? @template.content_tag(:ul, html, html_attributes) : html
  end

end

The above code is based on the PaginationLinkListRenderer from my older will_paginate blog.

Comment on 'Revisited: roll your own pagination links with will_paginate and Rails 3' by Gourav Tiwari

2011-05-25T21:02:32Z

I was using will_paginate plugin and wanted not to display previous page/next page when user on first page/last page (sorry not upgraded to latest version yet :( ). I ended up doing small extension:

class PaginationLinkRenderer < WillPaginate::LinkRenderer
  protected

  def page_span(page, text, attributes = {})
    is_disabled_prev_or_next?(attributes) ? '' : @template.content_tag(:span, text, attributes)
  end

  def is_disabled_prev_or_next? attributes
    dont_show_defaults_for = ["disabled next_page", "disabled prev_page"]
    !attributes.blank? and dont_show_defaults_for.include? attributes[:class]
  end
end

Comment on 'Revisited: roll your own pagination links with will_paginate and Rails 3' by yoshyosh

2011-05-25T12:50:31Z

Hey guys, you might get an error about uninitialized constant PaginationLinkRenderer (ActionView::Template::Error) even after doing all of the autoloader stuff. I got it solved at stackover flow heres the link http://stackoverflow.com/questions/6122314/rails-autoloading-lib-not-working . Basically you need another file.

I was wondering how can I make Previous and Next show up as images rather than text? I tried putting image_path("") into the :previous_label and :next_label but that didn't even compile.

Comment on 'Revisited: roll your own pagination links with will_paginate and Rails 3' by AnGQ

2011-05-22T08:01:52Z

Hi Rob,

Thank you very much for pointing me out the way to live with will_paginate in Rails 3. I'm going to find a new life with these news in Rails 3 later.

By the way, with my old app, I've tried with some hacks in PaginationListLinkRenderer by using some functions from will_paginate 2.x.x, and all of my old things worked.

AnGQ

Comment on 'Protecting your Paperclip downloads' by Matt

2011-05-21T22:26:19Z

Hi!

Very nice this tutorial and explanations! But I have a problem with capistrano deployment. How could I symlink the folder outside the public folder, which contains my uploads? I don't use S3.

Anyone an idea?

Matt

Comment on 'Video thumbnails with FFmpeg and Paperclip' by Rob Anderton

2011-05-19T09:17:42Z

It might be worth putting a breakpoint in the rescue block of the make method and inspecting the values of the original exception message and output attributes (before the exception is re-raised) to be sure that it is the warning that is causing the error and not something else.

I've had FFmpeg warnings before that haven't stopped Paperclip from doing its thing - so I'd be interested to know why it's breaking your code.

Comment on 'Video thumbnails with FFmpeg and Paperclip' by erwin

2011-05-19T07:34:48Z

thanks for all these info .. it's running so well... However I got a, issue trying to generate thumbnail for an .m4v video file the ffmpeg command line on console works well .. ( it generates the thumbnail) but display a warning ...

ffmpeg -ss 2 -i clipout12-iPhone.m4v -y -vcodec mjpeg -f image2 -vframes 1 -s 100x74 clipout12-iPhone.jpg .. Seems stream 1 codec frame rate differs from container frame rate: 2000.00 (2000/1) -> 1000.00 (2000/2)

running the command line within Paperclip processor raises a PaperclipCommandLineError and the thumbnail is not generated.. is there anyway to avoid this 'frame rate' checking or should I bypass the error in the rescue ? ...

Comment on 'Revisited: roll your own pagination links with will_paginate and Rails 3' by Rob Anderton

2011-05-16T17:30:27Z

Rails 3 deprecated the remote_function method: inline scripting is no longer fashionable (with good reason) and unobtrusive is the way to go!

There is an example of Ajax pagination on the will_paginate wiki for Rails 3 which should get you started.

Comment on 'Protecting your Paperclip downloads' by Rob Anderton

2011-05-16T16:44:15Z

@Justin: sorry I missed your question - you've probably figured something out by now. If you're using a newer version of Paperclip, the expiring_url method is now part of the attachment model, so each one would have its own copy of the method.

Using older versions of Paperclip, probably the easiest thing to do would be to modify the code to accept the attachment object as a parameter too:

def download_url(attachment, style = nil, include_updated_timestamp = true)
  url = Paperclip::Interpolations.interpolate('/:class/:id/:style.:extension', attachment, style || attachment.default_style)
  include_updated_timestamp && attachment.updated_at ? [url, attachment.updated_at].compact.join(url.include?("?") ? "&" : "?") : url
end

def authenticated_url(attachment, style = nil, expires_in = 10.seconds)
  AWS::S3::S3Object.url_for(attachment.path(style || attachment.default_style), attachment.bucket_name, :expires_in => expires_in, :use_ssl => attachment.s3_protocol == 'https')
end

Comment on 'Protecting your Paperclip downloads' by Rob Anderton

2011-05-16T16:27:34Z

@Paul yep it's a typo: if we had a prize for paying attention you'd win it as nobody else has spotted the goof in the last couple of years!

@AdamGold: glad to help! The authenticated URL is time based, so by setting a short expiry time (for example the 10 seconds I've used in the examples above) you give time to allow the client to access the data but once the 10 seconds have elapsed the link no longer works (so sharing with friends would be pointless, unless they can use it within the 10 seconds!). I'm not aware of any way of having a one-time URL instead.

Comment on 'Protecting your Paperclip downloads' by AdamGold

2011-05-15T16:21:41Z

You're one of the bests ;) Really good article Rob, only I have one question - How can I re-generate the link each time? I mean, I want it to be expired -> re-generated so the user won't be able to share it with friends. Is it possible? Thanks!

Comment on 'Revisited: roll your own pagination links with will_paginate and Rails 3' by AnGQ

2011-05-06T06:53:27Z

In the previous version of Rails (2.3.5), I used will_paginate with something like:


<%= will_paginate(@posts,
                  :inner_window => 1,
                  :outer_window => 0,
                  :function     => remote_function(
                    :submit=> "option_items",                                                            
                    :before=>"$('spinner').show()",
                    :complete  => "$('spinner').hide()",
                    :url       => {
                      :controller       => "post",
                      :action           => requested_action,
                      :page             => "__page__"
                    }
                  )
)%>

But with this new will_paginate (3.0.pre2), :function => remote_function do not work any more. I've changed my sourcecode to:

<%= will_paginate(@posts,
                  :inner_window => 1,
                  :outer_window => 0,
                  :params     =>{
                    :submit=> "option_items",                                                        
                    :before=>"$('spinner').show()",
                    :complete  => "$('spinner').hide()",
                    :controller       => "post",
                    :action           => requested_action,
                    :page             => "__page__"
                  }
)%>

The Controller and Action can be called, but the :submit options or :before, :complete do not work. How should I change my source code?

Comment on 'Rails 2.1: now with better integrated caching' by Farukh D M

2011-05-04T10:04:23Z

Awesomely documented :)

Comment on 'Protecting your Paperclip downloads' by Paul

2011-04-26T17:19:00Z

Wow, thank you for writing this up! It's a great work-around for the (understandable) limitations of S3 access control.

I think this is a mental typo, right?:

And while I’m at it, I can also move the authenticated S3 URL generation out of the model and into the controller too.

I believe that should read:

And while I’m at it, I can also move the authenticated S3 URL generation out of the controller and into the model too.

Paul

Comment on 'RSpec, autotest and Snarl on Windows' by Rob Anderton

2011-04-08T17:17:12Z

Unfortunately it looks like ruby-snarl won't work with Ruby 1.9 - the DL library has been changed (DL::Importable no longer exists) and ruby-snarl hasn't seen an update for nearly five years.

There is the autotest-snarl which looks like it could be a replacement, but I've not tried it.