Don't error when size is called on a deleted file

[danielevans]

When using Fog and AWS and a new file is uploaded and the old file is missing content_length is called on nil, resulting in the inability to upload a new file.

This change updates the CarrierWave::Storage::Fog class such that it will not error if this situation occurs and instead return a 0 file size.

It seems that this change could also be made in https://github.com/carrierwaveuploader/carrierwave/blob/master/lib/carrierwave/sanitized_file.rb#L136 by reversing the conditional (self.size.zero? && ! self.exists?), however the change in this PR seemed less invasive.

The error caused by this issue:

NoMethodError: undefined method `content_length' for nil:NilClass
    from /srv/app/releases/20150213002036/vendor/bundle/ruby/2.1.0/bundler/gems/carrierwave-0033279be9b6/lib/carrierwave/storage/fog.rb:291:in `size'
    from /srv/app/releases/20150213002036/vendor/bundle/ruby/2.1.0/bundler/gems/carrierwave-0033279be9b6/lib/carrierwave/uploader/proxy.rb:57:in `size'
    from /srv/app/releases/20150213002036/vendor/bundle/ruby/2.1.0/bundler/gems/carrierwave-0033279be9b6/lib/carrierwave/sanitized_file.rb:96:in `size'
    from /srv/app/releases/20150213002036/vendor/bundle/ruby/2.1.0/bundler/gems/carrierwave-0033279be9b6/lib/carrierwave/sanitized_file.rb:136:in `empty?'
    from /srv/app/releases/20150213002036/vendor/bundle/ruby/2.1.0/bundler/gems/carrierwave-0033279be9b6/lib/carrierwave/uploader/cache.rb:111:in `cache!'
    from /srv/app/releases/20150213002036/vendor/bundle/ruby/2.1.0/bundler/gems/carrierwave-0033279be9b6/lib/carrierwave/mounter.rb:43:in `block in cache'
    from /srv/app/releases/20150213002036/vendor/bundle/ruby/2.1.0/bundler/gems/carrierwave-0033279be9b6/lib/carrierwave/mounter.rb:41:in `map'
    from /srv/app/releases/20150213002036/vendor/bundle/ruby/2.1.0/bundler/gems/carrierwave-0033279be9b6/lib/carrierwave/mounter.rb:41:in `cache'
    from /srv/app/releases/20150213002036/vendor/bundle/ruby/2.1.0/bundler/gems/carrierwave-0033279be9b6/lib/carrierwave/mount.rb:148:in `avatar='

[bhavinjavia]

+1. we're running into this issue as well

[bensie]

Thanks @danielevans!

[ghost]

we are running too, thanks

[ghost]

I just got

undefined method `content_length' for nil:NilClass

When updating an image, i'm using latest carrierwave with rails 4.

Thanks!

[danielevans]

@amartell-smx Looks like this didn't make it into the 0.10.0 release. Have you tried using the latest master branch?

[ghost]

Got this message

/Users/abimael/.rbenv/versions/2.1.4/lib/ruby/gems/2.1.0/bundler/gems/carrierwave-45d90749693f/lib/carrierwave/uploader/configu
ration.rb:75:in `eval': uninitialized constant CarrierWave::Storage::Fog (NameError)

With master, still i don't want to use master version on production, is there any way to workaround the size issue?

Thanks!

[danielevans]

You could easily monkey-patch the fix in.
The following code could go in lib/ext/carrierwave/storage/fog.rb and required the file from config/application.rb or an initializer.

require 'carrierwave/storage/fog'

class CarrierWave::Storage::Fog::File
  def size
    file.nil? ? 0 : file.content_length
  end
end

[ghost]

Actually it should be

require 'carrierwave/storage/fog'

class CarrierWave::Storage::Fog::File
  def size
    file.nil? ? 0 : file.content_length
  end
end

Thanks!

[danielevans]

Gah, thanks. I edited mine to make sure nobody copy-pastes the bad code.

[jvenezia]

Still not in the lastest release (0.11.0). Is there a reason not to release this ? I'll monkey-patch for the moment.

[jvenezia]

Same problem with content_type: #1915