Some refactorings, safer regex

lib/diaspora.rb

@@ -3,12 +3,13 @@
 #   the COPYRIGHT file.
 
 module Diaspora
+  require 'diaspora/camo'
   require 'diaspora/exceptions'
-  require 'diaspora/parser'
-  require 'diaspora/fetcher'
-  require 'diaspora/markdownify'
-  require 'diaspora/message_renderer'
-  require 'diaspora/mentionable'
   require 'diaspora/exporter'
   require 'diaspora/federated'
+  require 'diaspora/fetcher'
+  require 'diaspora/markdownify'
+  require 'diaspora/mentionable'
+  require 'diaspora/message_renderer'
+  require 'diaspora/parser'
 end

lib/diaspora/camo.rb

@@ -0,0 +1,31 @@
+# implicitly requires OpenSSL
+module Diaspora
+  module Camo
+    def self.from_markdown(markdown_text)
+      markdown_text.gsub(/(!\[(.*?)\]\s?\([ \t]*()<?(\S+?)>?[ \t]*((['"])(.*?)\6[ \t]*)?\))/m) do |link|
+        link.gsub($4, self.image_url($4))
+      end
+    end
+
+    def self.image_url(url)
+      return unless url
+      return url unless self.url_eligible?(url)
+
+      digest = OpenSSL::HMAC.hexdigest(
+        OpenSSL::Digest.new('sha1'),
+        AppConfig.privacy.camo.key,
+        url
+      )
+
+      encoded_url = url.to_enum(:each_byte).map {|byte| '%02x' % byte}.join
+      "#{AppConfig.privacy.camo.root}#{digest}/#{encoded_url}"
+    end
+
+    def self.url_eligible?(url)
+      return false unless url.start_with?('http', '//')
+      return false if url.start_with?(AppConfig.environment.url.to_s,
+                                      AppConfig.privacy.camo.root.to_s)
+      true
+    end
+  end
+end

lib/diaspora/camo_url.rb

@@ -1,16 +0,0 @@
-# implicitly requires OpenSSL
-
-module Diaspora
-  module CamoUrl
-    def self.image_url(url)
-      digest = OpenSSL::HMAC.hexdigest(
-        OpenSSL::Digest.new("sha1"),
-        AppConfig.privacy.camo.key,
-        url
-      )
-      encoded_url = url.to_enum(:each_byte).map {|byte| "%02x" % byte}.join
-
-      "#{AppConfig.privacy.camo.root}#{digest}/#{encoded_url}"
-    end
-  end
-end

lib/diaspora/message_renderer.rb

@@ -89,9 +89,7 @@ module Diaspora
       end
 
       def camo_urls
-        @message = @message.gsub(/!\[.*?\]\((.+?)\)/) do |link|
-          link.gsub($1, Diaspora::CamoUrl::image_url($1))
-        end
+        @message = Diaspora::Camo::from_markdown(@message)
       end
     end
 

spec/lib/diaspora/camo_spec.rb

@@ -0,0 +1,50 @@
+#   Copyright (c) 2010, Diaspora Inc.  This file is
+#   licensed under the Affero General Public License version 3 or later.  See
+#   the COPYRIGHT file.
+
+require 'spec_helper'
+
+describe Diaspora::Camo do
+  before do
+    AppConfig.privacy.camo.root = 'http://localhost:3000/camo/'
+    AppConfig.privacy.camo.key = 'kittenpower'
+
+    @raw_image_url = 'http://example.com/kitten.jpg'
+    @camo_image_url = "#{AppConfig.privacy.camo.root}5bc5b9d7ebd202841ab0667c4fc8d4304278f902/687474703a2f2f6578616d706c652e636f6d2f6b697474656e2e6a7067"
+  end
+
+  describe '#image_url' do
+    it 'should not rewrite local URLs' do
+      local_image = "#{AppConfig.environment.url}kitten.jpg"
+      expect(Diaspora::Camo::image_url(local_image)).to eq(local_image)
+    end
+
+    it 'should not rewrite relative URLs' do
+      relative_image = "/kitten.jpg"
+      expect(Diaspora::Camo::image_url(relative_image)).to eq(relative_image)
+    end
+
+    it 'should not rewrite already camo-fied URLs' do
+      camo_image = "#{AppConfig.privacy.camo.root}1234/56789abcd"
+      expect(Diaspora::Camo::image_url(camo_image)).to eq(camo_image)
+    end
+
+    it 'should rewrite external URLs' do
+      expect(Diaspora::Camo::image_url(@raw_image_url)).to eq(@camo_image_url)
+    end
+  end
+
+  describe '#from_markdown' do
+    it 'should rewrite plain markdown images' do
+      expect(Diaspora::Camo::from_markdown("![](#{@raw_image_url})")).to include(@camo_image_url)
+    end
+
+    it 'should rewrite markdown images with alt texts' do
+      expect(Diaspora::Camo::from_markdown("![a kitten](#{@raw_image_url})")).to include(@camo_image_url)
+    end
+
+    it 'should rewrite markdown images with title texts' do
+      expect(Diaspora::Camo::from_markdown("![](#{@raw_image_url}) \"title\"")).to include(@camo_image_url)
+    end
+  end
+end