Add word list cache invalidation mechanism to refresh the word list after 30 days

Author: rameerez

lib/moderate/word_list.rb

@@ -8,17 +8,24 @@
 module Moderate
   class WordList
     WORD_LIST_URL = 'https://raw.githubusercontent.com/coffee-and-fun/google-profanity-words/main/data/en.txt'
+    CACHE_TTL = 30 * 24 * 60 * 60 # 30 days in seconds
 
     class << self
       def load
         cache_path = cache_file_path
 
         begin
           if File.exist?(cache_path)
-            words = File.read(cache_path, encoding: 'UTF-8').split("\n").to_set
-            return words unless words.empty?
+            if cache_valid?(cache_path)
+              words = File.read(cache_path, encoding: 'UTF-8').split("\n").to_set
+              return words unless words.empty?
+            else
+              logger.info("[moderate gem] Cache expired (older than #{CACHE_TTL / 86400} days). Refreshing word list...")
+              return download_and_cache(cache_path)
+            end
           end
 
+          logger.info("[moderate gem] No cache found. Downloading word list for the first time...")
           download_and_cache(cache_path)
         rescue StandardError => e
           logger.error("[moderate gem] Error loading word list: #{e.message}")
@@ -27,8 +34,22 @@ def load
         end
       end
 
+      def refresh_word_list!
+        logger.info("[moderate gem] Manually refreshing word list")
+        cache_path = cache_file_path
+        File.delete(cache_path) if File.exist?(cache_path)
+        download_and_cache(cache_path)
+      end
+
       private
 
+      def cache_valid?(cache_path)
+        return false unless File.exist?(cache_path)
+
+        cache_age = Time.now - File.mtime(cache_path)
+        cache_age <= CACHE_TTL
+      end
+
       def cache_file_path
         if defined?(Rails)
           Rails.root.join('tmp', 'moderate_bad_words.txt')
@@ -52,7 +73,9 @@ def download_and_cache(cache_path)
           raise Moderate::Error, "Downloaded word list is empty"
         end
 
-        logger.info("[moderate gem] Downloaded #{words.size} words from #{WORD_LIST_URL}")
+        logger.info("[moderate gem] Successfully downloaded and cached #{words.size} words to #{cache_path}")
+        logger.info("[moderate gem] Next cache refresh will occur after: #{Time.now + CACHE_TTL}")
+
         File.write(cache_path, content, encoding: 'UTF-8')
         logger.debug("[moderate gem] Cached word list to: #{cache_path}")