Question

基本上，即使文件实际上不存在，photo_url（：thumb）也会显示预期的拇指网址。

# encoding: utf-8

class WinePhotoUploader < CarrierWave::Uploader::Base

    include CarrierWave::MiniMagick

    storage :file

    # So the :thumb will be stored in "public/assets/wines/thumb/2008-meritage-750mL.jpg" for example.
    def store_dir
        "assets/wines/#{version_name}"
    end

    def cache_dir
        Rails.root.join 'tmp/uploads'
    end

    CarrierWave::SanitizedFile.sanitize_regexp = /[^[:word:]\.\-\+]/

    # If no version name is present (original), just provide the thumb path
    # This method is never called!!! Why not?
    def default_url
        ActionController::Base.helpers.asset_path("pages/wines/#{version_name || :thumb}/default.png")
    end

    # To save disk space, make sure the original image is no larger than the croppable + a few pixels
    process :resize_to_fit => [2000, 2000]

    version :croppable, :if => :not_cropping? do
        process :common
        process :resize_and_pad => [1200, 1200, :white]
        process :convert => "jpg"
        # Override the default naming convention...I store in folders,
        # so I don't want the version prepended to the file name.
        def full_filename(for_file = model.photo.file)
            the_filename
        end
    end

    version :show, :if => :not_cropping? do
        process :resize_to_show
        process :convert => "jpg"
        def full_filename(for_file = model.photo.file)
            the_filename
        end
    end

    version :thumb, :from_version => :croppable, :if => :viewing_or_cropping? do
        process :custom_thumbnail => [200, 200]
        def full_filename(for_file = model.photo.file)
            the_filename
        end
    end




    def common(q=100, s='1.2x1+0.75+0.05')
        manipulate! do |img|
            img.combine_options do |i|
            i.quality q
            i.antialias
            i.background :white
            i.flatten
            i.density 72
            i.profile "#{Rails.root}/lib/color_profiles/sRGB_v4_ICC_preference_displayclass.icc"
            i.strip
            end
            img = yield(img) if block_given?
            img.combine_options do |i|
            i.unsharp s
            end
            img
        end
    end

    def resize_to_show
        common do |img|
            img.combine_options do |i|
            i.trim
            i.thumbnail 110
            i.background :white
            i.gravity :center
            i.extent 170
            end
            img
        end
    end

    def custom_thumbnail(width, height)
        manipulate! do |img|
            img.combine_options do |i|
            i.distort :srt, "#{model.crop_x},#{model.crop_y} 1 -30 600,600"
            i.repage.+
            i.gravity :center
            i.crop "#{model.crop_w}x#{model.crop_h}+0+0"
            i.repage.+
            i.thumbnail "#{width}x#{height}"
            i.unsharp '1.2x1+0.75+0.05'
            end
            img
        end
    end




    def not_cropping? picture
        !model.cropping?
    end
    # For some stupid reason, if I only check for 'model.cropping?' and
    # it returns false, the photo_url(:thumb) will always show the default_url
    # and never show the actual url! This is terrible logic. The version declarations
    # above should only affect the generation of thumbnails, not whether the call
    # to photo_url(:thumb) works.
    def viewing_or_cropping? picture
        model.cropping? or model.changes.merge(model.previous_changes).empty?
    end

    # Add a white list of extensions which are allowed to be uploaded.
    # For images you might use something like this:
    def extension_white_list
        %w(jpg jpeg gif png tif tiff)
    end

    # Only modify the version names, not the original uploaded file name
    def filename
        "#{ model.get_permalink(:normalized => true) }#{ File.extname original_filename }" if original_filename
    end

    # The filename should be the wine's permalink name (ex., 2008-merlot-reserve-750mL.jpg)
    def the_filename
        "#{ model.get_permalink(:normalized => true) }.jpg"
    end

    # Remove this when https://github.com/carrierwaveuploader/carrierwave/issues/1164 is solved.
    def recreate_versions!(*versions)
    if versions.any?
        from_versions = versions.group_by { |v| self.class.versions[v][:options][:from_version] }
        from_versions.each do |from, versions|
        next if from.nil?
        file = CarrierWave::SanitizedFile.new(self.versions[from.to_sym].file)
        store_versions!(file, versions)
        end
    else
        super(*versions)
    end
    end

end

所以打电话给@ wine.photo_url（：thumb）会产生

http://dev.mydomain.com/assets/wines/thumb/2006-cabernet-sauvignon-750mL.jpg

什么时候应该生产

http://dev.mydomain.com/assets/pages/wines/thumb/default.png

因为该文件不存在。

Answer 1

我最好的猜测是，Carrierwave根据数据库中模型属性的存在生成文件名，而不是文件的特定版本是否存在。不是我对default_url的期望，但它仍然以有限的方式有意义。

当版本不存在时，Carrierwave不使用default_url

1 个答案: