accept url strings

lib/paperclip.rb

@@ -191,3 +191,4 @@ require 'paperclip/io_adapters/nil_adapter'
 require 'paperclip/io_adapters/attachment_adapter'
 require 'paperclip/io_adapters/uploaded_file_adapter'
 require 'paperclip/io_adapters/uri_adapter'
+require 'paperclip/io_adapters/url_adapter'

lib/paperclip/io_adapters/url_adapter.rb

+module Paperclip
+  class UrlAdapter < UriAdapter
+
+    REGEXP = /^https?:\/\//
+
+    def initialize(target)
+      super(URI(target))
+    end
+
+  end
+end
+
+Paperclip.io_adapters.register Paperclip::UrlAdapter do |target|
+  String === target && target =~ Paperclip::UrlAdapter::REGEXP
+end

test/io_adapters/url_adapter_test.rb

+require './test/helper'
+
+class UrlProxyTest < Test::Unit::TestCase
+  context "a new instance" do
+    setup do
+      @open_return = StringIO.new("xxx")
+      @open_return.stubs(:content_type).returns("image/png")
+      Paperclip::UrlAdapter.any_instance.stubs(:download_content).returns(@open_return)
+      @url = "http://thoughtbot.com/images/thoughtbot-logo.png"
+      @subject = Paperclip.io_adapters.for(@url)
+    end
+
+    should "return a file name" do
+      assert_equal "thoughtbot-logo.png", @subject.original_filename
+    end
+
+    should 'close open handle after reading' do
+      assert_equal true, @open_return.closed?
+    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 @open_return.size, @subject.size
+    end
+
+    should "generate an MD5 hash of the contents" do
+      assert_equal Digest::MD5.hexdigest("xxx"), @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 "xxx", @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
+  end
+
+  context "a url with query params" do
+    setup do
+      Paperclip::UrlAdapter.any_instance.stubs(:download_content).returns(StringIO.new("xxx"))
+      @url = "https://github.com/thoughtbot/paperclip?file=test"
+      @subject = Paperclip.io_adapters.for(@url)
+    end
+
+    should "return a file name" do
+      assert_equal "paperclip", @subject.original_filename
+    end
+  end
+
+  context "a url with restricted characters in the filename" do
+    setup do
+      Paperclip::UrlAdapter.any_instance.stubs(:download_content).returns(StringIO.new("xxx"))
+      @url = "https://github.com/thoughtbot/paper:clip.jpg"
+      @subject = Paperclip.io_adapters.for(@url)
+    end
+
+    should "not generate filenames that include restricted characters" do
+      assert_equal "paper_clip.jpg", @subject.original_filename
+    end
+
+    should "not generate paths that include restricted characters" do
+      assert_no_match /:/, @subject.path
+    end
+  end
+
+end