added handler for (base64) data URIs

lib/paperclip.rb

@@ -186,6 +186,7 @@ require 'paperclip/io_adapters/empty_string_adapter'
 require 'paperclip/io_adapters/identity_adapter'
 require 'paperclip/io_adapters/file_adapter'
 require 'paperclip/io_adapters/stringio_adapter'
+require 'paperclip/io_adapters/data_uri_adapter'
 require 'paperclip/io_adapters/nil_adapter'
 require 'paperclip/io_adapters/attachment_adapter'
 require 'paperclip/io_adapters/uploaded_file_adapter'

lib/paperclip/io_adapters/data_uri_adapter.rb

+module Paperclip
+  class DataUriAdapter < StringioAdapter
+
+    REGEXP = /^data:([-\w]+\/[-\w\+]+);base64,(.*)/
+
+    def initialize(target)
+      @data_uri_parts = target.match(REGEXP) || []
+      deserialize
+      cache_current_values
+      @tempfile = copy_to_tempfile
+    end
+
+    private
+
+    def cache_current_values
+      self.original_filename = 'base64.txt'
+
+      @content_type = @data_uri_parts[1]
+      @content_type ||= 'text/plain'
+
+      @size = @target.size
+    end
+
+    def deserialize
+      @target = StringIO.new(Base64.decode64(@data_uri_parts[2]))
+    end
+
+  end
+end
+
+Paperclip.io_adapters.register Paperclip::DataUriAdapter do |target|
+  String === target && target =~ Paperclip::DataUriAdapter::REGEXP
+end

lib/paperclip/io_adapters/stringio_adapter.rb

@@ -3,7 +3,7 @@ module Paperclip
     def initialize(target)
       @target = target
       cache_current_values
-      @tempfile = copy_to_tempfile(@target)
+      @tempfile = copy_to_tempfile
     end
 
     attr_writer :content_type
@@ -21,8 +21,8 @@ module Paperclip
       @size = @target.size
     end
 
-    def copy_to_tempfile(src)
-      while data = src.read(16*1024)
+    def copy_to_tempfile
+      while data = @target.read(16*1024)
         destination.write(data)
       end
       destination.rewind

test/io_adapters/data_uri_adapter_test.rb

+require './test/helper'
+
+class DataUriAdapterTest < Test::Unit::TestCase
+  context "a new instance" do
+    setup do
+      @contents = "data:image/png;base64,dGVzdA=="
+      @subject = Paperclip.io_adapters.for(@contents)
+    end
+
+    should "return a file name" do
+      assert_equal "base64.txt", @subject.original_filename
+    end
+
+    should "return a content type" do
+      assert_equal "image/png", @subject.content_type
+    end
+
+    should "return the size of the data" do
+      assert_equal 4, @subject.size
+    end
+
+    should "generate an MD5 hash of the contents" do
+      assert_equal Digest::MD5.hexdigest(Base64.decode64('dGVzdA==')), @subject.fingerprint
+    end
+
+    should "generate correct fingerprint after read" do
+      fingerprint = Digest::MD5.hexdigest(@subject.read)
+      assert_equal fingerprint, @subject.fingerprint
+    end
+
+    should "generate same fingerprint" do
+      assert_equal @subject.fingerprint, @subject.fingerprint
+    end
+
+    should "return the data contained in the StringIO" do
+      assert_equal "test", @subject.read
+    end
+
+    should 'accept a content_type' do
+      @subject.content_type = 'image/png'
+      assert_equal 'image/png', @subject.content_type
+    end
+
+    should 'accept an original_filename' do
+      @subject.original_filename = 'image.png'
+      assert_equal 'image.png', @subject.original_filename
+    end
+
+    should "not generate filenames that include restricted characters" do
+      @subject.original_filename = 'image:restricted.png'
+      assert_equal 'image_restricted.png', @subject.original_filename
+    end
+
+    should "not generate paths that include restricted characters" do
+      @subject.original_filename = 'image:restricted.png'
+      assert_no_match /:/, @subject.path
+    end
+
+  end
+end