FIX: clicks counter on attachments wasn't always working

app/models/topic_link_click.rb

@@ -1,5 +1,10 @@
 require_dependency 'discourse'
 require 'ipaddr'
+require 'url_helper'
+
+class TopicLinkClickHelper
+  include UrlHelper
+end
 
 class TopicLinkClick < ActiveRecord::Base
   belongs_to :topic_link, counter_cache: :clicks
@@ -10,15 +15,27 @@ class TopicLinkClick < ActiveRecord::Base
 
   # Create a click from a URL and post_id
   def self.create_from(args={})
+    url = args[:url]
+    return nil if url.blank?
 
-    # If the URL is absolute, allow HTTPS and HTTP versions of it
-    if args[:url] =~ /^http/
-      http_url = args[:url].sub(/^https/, 'http')
-      https_url = args[:url].sub(/^http\:/, 'https:')
-      link = TopicLink.select([:id, :user_id]).where('url = ? OR url = ?', http_url, https_url)
-    else
-      link = TopicLink.select([:id, :user_id]).where(url: args[:url])
+    helper = TopicLinkClickHelper.new
+    uri = URI.parse(url) rescue nil
+
+    urls = Set.new
+    urls << url
+    if url =~ /^http/
+      urls << url.sub(/^https/, 'http')
+      urls << url.sub(/^http:/, 'https:')
+      urls << helper.schemaless(url)
     end
+    urls << helper.absolute_without_cdn(url)
+    urls << uri.path if uri.try(:host) == Discourse.current_hostname
+    urls << url.sub(/\?.*$/, '') if url.include?('?')
+
+    link = TopicLink.select([:id, :user_id])
+
+    # test for all possible URLs
+    link = link.where(Array.new(urls.count, "url = ?").join(" OR "), *urls)
 
     # Find the forum topic link
     link = link.where(post_id: args[:post_id]) if args[:post_id].present?
@@ -27,23 +44,18 @@ class TopicLinkClick < ActiveRecord::Base
     link = link.where(topic_id: args[:topic_id]) if args[:topic_id].present?
     link = link.first
 
-    # If no link is found, return the url for relative links
+    # If no link is found...
     unless link.present?
-      return args[:url] if args[:url] =~ /^\//
+      # ... return the url for relative links or when using the same host
+      return url if url =~ /^\// || uri.try(:host) == Discourse.current_hostname
 
-      begin
-        uri = URI.parse(args[:url])
-        return args[:url] if uri.host == URI.parse(Discourse.base_url).host
-      rescue
-      end
-
-      # If we have it somewhere else on the site, just allow the redirect. This is
-      # likely due to a onebox of another topic.
-      link = TopicLink.find_by(url: args[:url])
+      # If we have it somewhere else on the site, just allow the redirect.
+      # This is likely due to a onebox of another topic.
+      link = TopicLink.find_by(url: url)
       return link.present? ? link.url : nil
     end
 
-    return args[:url] if (args[:user_id] && (link.user_id == args[:user_id]))
+    return url if args[:user_id] && link.user_id == args[:user_id]
 
     # Rate limit the click counts to once in 24 hours
     rate_key = "link-clicks:#{link.id}:#{args[:user_id] || args[:ip]}"
@@ -52,7 +64,7 @@ class TopicLinkClick < ActiveRecord::Base
       create!(topic_link_id: link.id, user_id: args[:user_id], ip_address: args[:ip])
     end
 
-    args[:url]
+    url
   end
 
 end