Merge pull request #46 from curationexperts/struct

Represent the transformation as a struct, not a hash

app/models/riiif/file.rb

@@ -34,23 +34,23 @@ def self.create(ext = nil, _validate = true, &block)
 
     end
 
-    def extract(options)
-
+    # @param [Transformation] transformation
+    def extract(transformation)
       command = 'convert'
-      command << " -crop #{options[:crop]}" if options[:crop]
-      command << " -resize #{options[:size]}" if options[:size]
-      if options[:rotation]
-        command << " -virtual-pixel white +distort srt #{options[:rotation]}"
+      command << " -crop #{transformation.crop}" if transformation.crop
+      command << " -resize #{transformation.size}" if transformation.size
+      if transformation.rotation
+        command << " -virtual-pixel white +distort srt #{transformation.rotation}"
       end
 
-      case options[:quality]
+      case transformation.quality
       when 'grey'
         command << ' -colorspace Gray'
       when 'bitonal'
         command << ' -colorspace Gray'
         command << ' -type Bilevel'
       end
-      command << " #{path} #{options[:format]}:-"
+      command << " #{path} #{transformation.format}:-"
       execute(command)
     end
 

app/models/riiif/image.rb

@@ -52,7 +52,7 @@ def expires_in
 
 
       def cache_key(id, options)
-        str = options.merge(id: id).delete_if { |_, v| v.nil? }.to_s
+        str = options.to_h.merge(id: id).delete_if { |_, v| v.nil? }.to_s
         # Use a MD5 digest to ensure the keys aren't too long.
         Digest::MD5.hexdigest(str)
       end
@@ -62,14 +62,15 @@ def cache_key(id, options)
 
       ##
       # @param [ActiveSupport::HashWithIndifferentAccess] options
+      # @return [Transformation]
       def decode_options!(options)
         raise ArgumentError, "You must provide a format. You provided #{options}" unless options[:format]
-        options[:crop] = decode_region(options.delete(:region))
-        options[:size] = decode_size(options.delete(:size))
-        options[:quality] = decode_quality(options[:quality])
-        options[:rotation] = decode_rotation(options[:rotation])
         validate_format!(options[:format])
-        options
+        Riiif::Transformation.new(decode_region(options.delete(:region)),
+                                  decode_size(options.delete(:size)),
+                                  decode_quality(options[:quality]),
+                                  decode_rotation(options[:rotation]),
+                                  options[:format])
       end
 
       def decode_quality(quality)

lib/riiif.rb

@@ -20,5 +20,7 @@ def initialize(orig = nil)
     end
   end
 
+  Transformation = Struct.new(:crop, :size, :quality, :rotation, :format)
+
   mattr_accessor :not_found_image # the image to use when a lookup fails
 end