From 7ab0f052f335777ec4d3b0e4e71a72c4eef228c5 Mon Sep 17 00:00:00 2001
From: Rick Okin <rickokin@yahoo.com>
Date: Tue, 9 Aug 2005 01:58:16 +0000
Subject: [PATCH] Primitive spam filter

---
 app/controllers/wiki_controller.rb | 24 +++++++++++++++++++++++-
 config/environments/production.rb  | 11 +++++++++++
 2 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/app/controllers/wiki_controller.rb b/app/controllers/wiki_controller.rb
index 43d55b2e..8fcf3060 100644
--- a/app/controllers/wiki_controller.rb
+++ b/app/controllers/wiki_controller.rb
@@ -176,6 +176,9 @@ class WikiController < ApplicationController
     cookies['author'] = @params['author']
 
     begin
+      check_for_spam(@params['content'], remote_ip)
+      check_blocked_ips(remote_ip)
+
       if @page
         wiki.revise_page(@web_name, @page_name, @params['content'], Time.now, 
             Author.new(@params['author'], remote_ip))
@@ -227,7 +230,26 @@ class WikiController < ApplicationController
 
 
   private
-    
+
+  def check_blocked_ips(ip)
+    if defined? BLOCKED_IPS and not BLOCKED_IPS.nil?
+      BLOCKED_IPS.each do |blocked_ip|
+        raise Instiki::ValidationError.new('Revision rejected by spam filter') if ip == blocked_ip
+      end
+    end
+  end
+
+  def check_for_spam(new_content, ip)
+    if defined? SPAM_PATTERNS and not SPAM_PATTERNS.nil?
+      SPAM_PATTERNS.each do |pattern|
+        if new_content =~ pattern
+          logger.info "Spam attempt from IP address #{ip}"
+          raise Instiki::ValidationError.new('Revision rejected by spam filter')
+        end
+      end
+    end
+  end
+
   def convert_tex_to_pdf(tex_path)
     # TODO remove earlier PDF files with the same prefix
     # TODO handle gracefully situation where pdflatex is not available
diff --git a/config/environments/production.rb b/config/environments/production.rb
index e5b18783..02d9dcb9 100644
--- a/config/environments/production.rb
+++ b/config/environments/production.rb
@@ -2,3 +2,14 @@ Dependencies.mechanism = :require
 ActionController::Base.consider_all_requests_local = false
 ActionController::Base.perform_caching = false
 
+
+spam_patterns_filename = RAILS_ROOT + '/config/spam_patterns.txt'
+if File.exists? spam_patterns_filename
+  SPAM_PATTERNS = File.readlines(spam_patterns_filename).select { |line| line != '' }.map { 
+      |line| Regexp.new(line) }
+end
+
+blocked_ips_filename = RAILS_ROOT + '/config/blocked_ips.txt'
+if File.exists? blocked_ips_filename
+  BLOCKED_IPS = File.readlines(blocked_ips_filename).select { |line| line != '' }
+end