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chrisbloom7/01-validates-file-size-carrierwave.md

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A cheap knock off of the default validates_length_of validator, but checks the filesize of a Carrierwave attachment
Raw
01-validates-file-size-carrierwave.md

Note that this validation runs both after the file is uploaded and after CarrierWave has processed the image. If your base uploader includes a filter to resize the image then the validation will be run against the resized image, not the original one that was uploaded. If this causes a problem for you, then you should avoid using a resizing filter on the base uploader and put any specific size requirements in a version instead.

So instead of this:

require 'carrierwave/processing/mini_magick'

class LogoUploader < CarrierWave::Uploader::Base
  include CarrierWave::MiniMagick

  process :quality => 80
  process :resize_to_limit => [800, 800]
  process :convert => 'png'
  
  # ...
end

Do this:

require 'carrierwave/processing/mini_magick'

class LogoUploader < CarrierWave::Uploader::Base
  include CarrierWave::MiniMagick

  process :convert => 'png'

  version :medium do
    process :quality => 80
    process :resize_to_limit => [800, 800]
  end

  # ...

end
Raw
en.yml
# config/locales/en.yml
en:
errors:
messages:
wrong_size: "is the wrong size (should be %{file_size})"
size_too_small: "is too small (should be at least %{file_size})"
size_too_big: "is too big (should be at most %{file_size})"
Raw
file_size_validator.rb
# lib/file_size_validator.rb
# Based on: https://gist.github.com/795665
class FileSizeValidator < ActiveModel::EachValidator
MESSAGES = { :is => :wrong_size, :minimum => :size_too_small, :maximum => :size_too_big }.freeze
CHECKS = { :is => :==, :minimum => :>=, :maximum => :<= }.freeze
DEFAULT_TOKENIZER = lambda { |value| value.split(//) }
RESERVED_OPTIONS = [:minimum, :maximum, :within, :is, :tokenizer, :too_short, :too_long]
def initialize(options)
if range = (options.delete(:in) || options.delete(:within))
raise ArgumentError, ":in and :within must be a Range" unless range.is_a?(Range)
options[:minimum], options[:maximum] = range.begin, range.end
options[:maximum] -= 1 if range.exclude_end?
end
super
end
def check_validity!
keys = CHECKS.keys & options.keys
if keys.empty?
raise ArgumentError, 'Range unspecified. Specify the :within, :maximum, :minimum, or :is option.'
end
keys.each do |key|
value = options[key]
unless value.is_a?(Integer) && value >= 0
raise ArgumentError, ":#{key} must be a nonnegative Integer"
end
end
end
def validate_each(record, attribute, value)
raise(ArgumentError, "A CarrierWave::Uploader::Base object was expected") unless value.kind_of? CarrierWave::Uploader::Base
value = (options[:tokenizer] || DEFAULT_TOKENIZER).call(value) if value.kind_of?(String)
CHECKS.each do |key, validity_check|
next unless check_value = options[key]
value ||= [] if key == :maximum
value_size = value.size
next if value_size.send(validity_check, check_value)
errors_options = options.except(*RESERVED_OPTIONS)
errors_options[:file_size] = help.number_to_human_size check_value
default_message = options[MESSAGES[key]]
errors_options[:message] ||= default_message if default_message
record.errors.add(attribute, MESSAGES[key], errors_options)
end
end
def help
Helper.instance
end
class Helper
include Singleton
include ActionView::Helpers::NumberHelper
end
end
@saeedSarpas
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What is the right way to set maximum file size amount for test env?
I did something like this:

file_size: { maximum: (Rails.env.test? ? 1.megabytes.to_i : 5.megabytes.to_i }

but I don't feel it's right.

@jmuheim
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jmuheim commented Jul 19, 2014

@saeedSarpas: I'm thinking about this, too. Is there a way to stub the validation within the test itself?

At least, I prettified your code a little:

validates :avatar, file_size: {maximum: (Rails.env.test? ? 5 : 100).kilobytes.to_i}

@heartfulbird
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Hi! I'm using carrierwave and file_size_validator
and I'm using sidekiq
and when I run "bundle exec sidekiq " in console
i see this errors
.../lib/file_size_validator.rb:5: warning: already initialized constant FileSizeValidator::MESSAGES
and the same about
FileSizeValidator::CHECKS
and ::DEFAULT_TOKENIZER
and ::RESERVED_OPTIONS

@musaffa
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musaffa commented Dec 11, 2014

file validators gem does file validations more elegantly. It also supports validations both before and after uploads.

@pioz
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pioz commented Apr 22, 2015

File geometry validator: https://gist.github.com/pioz/6b38e26c311d525fb48a

@vinayvinay
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Can anyone help me resolve this error that comes up while using this validator? For some reason the value.size calls .content_length on a nil.

lib/file_size_validator.rb:47:in `block in validate_each'
NoMethodError (undefined method `content_length' for nil:NilClass):
lib/file_size_validator.rb:42:in `each'
lib/file_size_validator.rb:42:in `validate_each'

@ch3m1c
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ch3m1c commented Nov 24, 2015

Anyone using this with multiple files upload from Carrierwave? :)

@osnysantos
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Im getting the same error as @vinayvinay

It seems that the asset was removed out of app and file_size_validator try to validate an nonexistent file.

@mariorcardoso
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@osnysantos I was experiencing the same error because the asset was not present (the url was broken). I added the the line next if value.present? && !(value.file.exists?) inside the validate_each loop so I don't get an exception when the file url is broken. It seems to work fine so far. If the url is broken I don't need to validate the file size.

checks.each do |key, validity_check|
      next unless check_value = options[key]

      value ||= [] if key == :maximum
      next if value.present? && !(value.file.exists?)

      value_size = value.size
      next if value_size.send(validity_check, check_value)

@pinty
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pinty commented Jun 27, 2017 •
edited
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Hello @chrisbloom7
As we would like to use your source code present on this page, is there any chance that we can get a license for the code written by you into the following file file_size_validator.rb ? We couldn't find any.
Thank you!

@alexanderadam
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alexanderadam commented Aug 5, 2017 •
edited
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Hey @pinty,

it's possible to replace it with file_validators gem mentioned above by it's author which has the MIT license.
Besides from that it's properly packaged, has specs and a dedicated issue tracker.

PS: I'm pretty sure I'm reading a document you (co-)authored 😉

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