conditional convert options paperclip

Question

After some research I was able to add styles based on my image_class column.

Model.rb

has_attached_file :image,
                  :styles => lambda { |attachment| attachment.instance.decide_styles }

def decide_styles
  styles = {}

  case self.image_class
    when "poster"
      styles[:thumb] = ["30x45!", :jpg]
      styles[:standard] = ["185x278!", :jpg]
      styles[:expanded] = ["372x559!", :jpg]
      styles[:big] = ["600x900!", :jpg]
    when "cover"
      styles[:thumb] = ["30x45!", :jpg]
      styles[:standard] = ["300x1200!", :jpg]
  end

  styles
end

This works smoothly, now I wanted to add conditional convert_options as well. This somehow fails.

has_attached_file :image,
                  :styles => lambda { |attachment| attachment.instance.decide_styles }, 
                  :convert_options => lambda { |attachment| attachment.instance.decide_convert_options }

def decide_styles
  ...
end

def decide_convert_options

  opshunz = {}
  case self.image_class
    when "poster"
      opshunz[:thumb] = "-flop"
      opshunz[:standard] = "-flop"
      opshunz[:expanded] = "-flop"
      opshunz[:big] = "-flop"

    when "cover"
      opshunz[:thumb] = "-enhance"
      opshunz[:standard] = "-enhance"
  end

  opshunz
end

Error:

NoMethodError: undefined method `instance' for :all:Symbol

from /Users/AnsPoluke/Sites/nulike/app/models/movie_image.rb:8:in `block in <class:MovieImage>'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:431:in `[]'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:431:in `process_options'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:423:in `extra_options_for'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/style.rb:56:in `convert_options'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/style.rb:79:in `block in processor_options'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/style.rb:78:in `each'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/style.rb:78:in `processor_options'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:462:in `block in post_process_style'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:461:in `each'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:461:in `inject'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:461:in `post_process_style'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:454:in `block in post_process_styles'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:453:in `each'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:453:in `post_process_styles'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:445:in `block (2 levels) in post_process'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/activesupport-4.0.2/lib/active_support/callbacks.rb:393:in `_run__3861360263242897910__image_post_process__callbacks'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/activesupport-4.0.2/lib/active_support/callbacks.rb:80:in `run_callbacks'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/callbacks.rb:36:in `run_paperclip_callbacks'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:443:in `block in post_process'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/activesupport-4.0.2/lib/active_support/callbacks.rb:383:in `_run__3861360263242897910__post_process__callbacks'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/activesupport-4.0.2/lib/active_support/callbacks.rb:80:in `run_callbacks'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/callbacks.rb:36:in `run_paperclip_callbacks'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:442:in `post_process'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/attachment.rb:114:in `assign'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/paperclip-4.1.1/lib/paperclip/has_attached_file.rb:66:in `block in define_setter'
from (irb):2
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/railties-4.0.2/lib/rails/commands/console.rb:90:in `start'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/railties-4.0.2/lib/rails/commands/console.rb:9:in `start'
from /Users/AnsPoluke/.rvm/gems/ruby-2.1.0/gems/railties-4.0.2/lib/rails/commands.rb:62:in `<top (required)>'
from bin/rails:4:in `require'

Any ideas why it works perfectly with styles but fails with convert_options?

Answer 1

note: haven't verified that on working code

It seems that the argument to the block passed in :convert_options is already an instance, not the attachment (as opposed to styles option, where it is an attachment)

Try:

convert_options: lambda { |instance| instance.decide_convert_options }

Btw your code would look much better if you extract the configuration data, for example:

has_attached_file :image,
  styles: lambda { |attachment| attachment.instance.image_options[:styles] }, 
  convert_options: lambda { |instance| instance.image_options[:convert_options] }


IMAGE_OPTIONS = {
  poster: {
    styles: {
      thumb: ["30x45!", :jpg],
      standard: ["185x278!", :jpg],
      expanded: ["372x559!", :jpg]
      big: ["600x900!", :jpg]
    },
    convert_options: {
      thumb: "-flop",
      standard: "-flop",
      expanded: "-flop",
      big: = "-flop"
    }
  },
  cover: {
    styles: {
      thumb: ["30x45!", :jpg],
      standard: ["300x1200!", :jpg]
    },
    convert_options: {
      thumb: "-enhance",
      standard: "-enhance"
    }
  }
}

def image_options
  IMAGE_OPTIONS[self.image_class]
end

I hope that helps

Update:

it looks like your convert_options are not being set here: https://github.com/thoughtbot/paperclip/blob/a93dfc773b4fd649db4d1281b42a2a71b1ae72ff/lib/paperclip/style.rb#L55

it seems they recommend passing convert_options with styles, like in this spec: https://github.com/thoughtbot/paperclip/blob/263a498195d47563a6227be18cf4463c4c6e7903/spec/paperclip/style_spec.rb#L41

can you try this? so remove convert_options entirely, and in your configuration return hash like:

IMAGE_OPTIONS = {
      poster: {
        styles: {
          thumb: {
            geometry: "30x45!",
            format: :jpg,
            convert_options: '-flop',
          },
          standard: {...}
          expanded: {...}
          big: {...}
        }
      },
      cover: {
        styles: {...}

Answer 2

Apply it to all since that's what you're doing anyway?

:convert_options => {:all => "-flop"}

failing that you might be looking at creating a Paperclip Processor

Answer 3

The approved answer doesn't work. It can be read in the comments and the author acknowledges that it hasn't been tested in code.

This code does work:

has_attached_file :image,
                  :styles => lambda { |attachment|

                    thumb_convert_options = case attachment.instance.image_class
                      when "poster"
                        "-flop"
                      when "cover"
                        "-enhance"
                    end

                    {
                      thumb: {
                        convert_options: thumb_convert_options
                      }
                    }
                  }

The correct approach is to have convert_options inside the styles lambda; having it as a separate lambda does not work, at least for Paperclip version 4.1 and higher.

To keep my answer in one place, I've put all the code inline and omitted all styles beside thumb. Obviously to implement this you should keep the method decide_convert_options.