Move escape_uri method to a more suitable place

app/models/topic_embed.rb

@@ -1,4 +1,5 @@
 require_dependency 'nokogiri'
+require_dependency 'url_helper'
 
 class TopicEmbed < ActiveRecord::Base
   include Trashable
@@ -26,16 +27,6 @@ class TopicEmbed < ActiveRecord::Base
     "\n<hr>\n<small>#{I18n.t('embed.imported_from', link: "<a href='#{url}'>#{url}</a>")}</small>\n"
   end
 
-  DOUBLE_ESCAPED_EXPR = /%25([0-9a-f]{2})/i
-
-  # Prevents double URL encode
-  # https://stackoverflow.com/a/37599235
-  def self.escape_uri(uri, pattern = URI::UNSAFE)
-    encoded = URI.encode(uri, pattern)
-    encoded.gsub!(DOUBLE_ESCAPED_EXPR, '%\1')
-    encoded
-  end
-
   # Import an article from a source (RSS/Atom/Other)
   def self.import(user, url, title, contents)
     return unless url =~ /^https?\:\/\//
@@ -87,7 +78,7 @@ class TopicEmbed < ActiveRecord::Base
   def self.find_remote(url)
     require 'ruby-readability'
 
-    url = escape_uri(url)
+    url = UrlHelper.escape_uri(url)
     original_uri = URI.parse(url)
     opts = {
       tags: %w[div p code pre h1 h2 h3 b em i strong a img ul li ol blockquote],
@@ -130,7 +121,7 @@ class TopicEmbed < ActiveRecord::Base
       src = node[url_param]
       unless (src.nil? || src.empty?)
         begin
-          uri = URI.parse(escape_uri(src))
+          uri = URI.parse(UrlHelper.escape_uri(src))
           unless uri.host
             uri.scheme = original_uri.scheme
             uri.host = original_uri.host
@@ -170,7 +161,7 @@ class TopicEmbed < ActiveRecord::Base
   # Convert any relative URLs to absolute. RSS is annoying for this.
   def self.absolutize_urls(url, contents)
     url = normalize_url(url)
-    uri = URI(escape_uri(url))
+    uri = URI(UrlHelper.escape_uri(url))
     prefix = "#{uri.scheme}://#{uri.host}"
     prefix << ":#{uri.port}" if uri.port != 80 && uri.port != 443
 

lib/final_destination.rb

@@ -2,6 +2,7 @@ require 'socket'
 require 'ipaddr'
 require 'excon'
 require 'rate_limiter'
+require 'url_helper'
 
 # Determine the final endpoint for a Web URI, following redirects
 class FinalDestination
@@ -237,7 +238,7 @@ class FinalDestination
   end
 
   def escape_url
-    TopicEmbed.escape_uri(
+    UrlHelper.escape_uri(
       CGI.unescapeHTML(@url),
       Regexp.new("[^#{URI::PATTERN::UNRESERVED}#{URI::PATTERN::RESERVED}#]")
     )

lib/url_helper.rb

@@ -21,4 +21,14 @@ class UrlHelper
     url.sub(/^http:/i, "")
   end
 
+  DOUBLE_ESCAPED_REGEXP ||= /%25([0-9a-f]{2})/i
+
+  # Prevents double URL encode
+  # https://stackoverflow.com/a/37599235
+  def self.escape_uri(uri, pattern = URI::UNSAFE)
+    encoded = URI.encode(uri, pattern)
+    encoded.gsub!(DOUBLE_ESCAPED_REGEXP, '%\1')
+    encoded
+  end
+
 end

spec/components/url_helper_spec.rb

@@ -79,4 +79,26 @@ describe UrlHelper do
 
   end
 
+  describe "#escape_uri" do
+    it "doesn't escape simple URL" do
+      url = UrlHelper.escape_uri('http://example.com/foo/bar')
+      expect(url).to eq('http://example.com/foo/bar')
+    end
+
+    it "escapes unsafe chars" do
+      url = UrlHelper.escape_uri("http://example.com/?a=\11\15")
+      expect(url).to eq('http://example.com/?a=%09%0D')
+    end
+
+    it "escapes non-ascii chars" do
+      url = UrlHelper.escape_uri('http://example.com/ماهی')
+      expect(url).to eq('http://example.com/%D9%85%D8%A7%D9%87%DB%8C')
+    end
+
+    it "doesn't escape already escaped chars" do
+      url = UrlHelper.escape_uri('http://example.com/foo%20bar/foo bar/')
+      expect(url).to eq('http://example.com/foo%20bar/foo%20bar/')
+    end
+  end
+
 end

spec/models/topic_embed_spec.rb

@@ -233,25 +233,4 @@ describe TopicEmbed do
     end
   end
 
-  context ".escape_uri" do
-    it "doesn't escape simple URL" do
-      url = TopicEmbed.escape_uri('http://example.com/foo/bar')
-      expect(url).to eq('http://example.com/foo/bar')
-    end
-
-    it "escapes unsafe chars" do
-      url = TopicEmbed.escape_uri("http://example.com/?a=\11\15")
-      expect(url).to eq('http://example.com/?a=%09%0D')
-    end
-
-    it "escapes non-ascii chars" do
-      url = TopicEmbed.escape_uri('http://example.com/ماهی')
-      expect(url).to eq('http://example.com/%D9%85%D8%A7%D9%87%DB%8C')
-    end
-
-    it "doesn't escape already escaped chars" do
-      url = TopicEmbed.escape_uri('http://example.com/foo%20bar/foo bar/')
-      expect(url).to eq('http://example.com/foo%20bar/foo%20bar/')
-    end
-  end
 end