v0.6 -- change of approach again...

plugin.rb

@@ -4,7 +4,7 @@
 
 # name: discourse-md5_authentication
 # about: A plugin to authenticate users with MD5 passwords from legacy systems
-# version: 0.5
+# version: 0.6
 # authors: saint
 # url: https://gitea.federated.computer/saint/discourse-md5_authentication.git
 
@@ -12,49 +12,64 @@
 after_initialize do
   # Define a module to contain the MD5 authentication logic
   module LegacyMd5Authentication
-    # Override the current_user method to include MD5 authentication
-    def current_user
-      # Attempt to find the current user using the standard Discourse method
-      user = super
-      return user if user
-
-      # Check for MD5 authentication if no user is found by the standard method
-      email_or_username = @request.params[:login]
-      password = @request.params[:password]
-
-      if email_or_username && password
-        # Log the start of the MD5 authentication attempt
-        Rails.logger.info("MD5 Auth: Attempting to authenticate #{email_or_username}")
+    # Override the log_on_user method to include MD5 authentication
+    def log_on_user(user, session, cookie_jar, opts = {})
+      # If the user has an MD5 password and the MD5 password option is passed
+      if user.custom_fields['md5_password'] && opts[:md5_password]
+        # Check if the provided MD5 password matches the stored MD5 password
+        if user.custom_fields['md5_password'] == Digest::MD5.hexdigest(opts[:md5_password])
+          # Update the user to use the new password and clear the MD5 password
+          user.update!(password: opts[:md5_password])
+          user.custom_fields['md5_password'] = nil
+          user.save_custom_fields
+        else
+          # Return nil if the MD5 password does not match
+          return nil
+        end
+      end
+      # Call the original log_on_user method
+      super
+    end
 
+    # Define a method to authenticate a user with an MD5 password
+    def authenticate_with_md5(username, password)
       # Find the user by username or email, ignoring case
-        user = User.find_by_username_or_email(email_or_username.downcase.strip)
-
-        # Log if a user with an MD5 password is found
-        if user && user.custom_fields['md5_password']
-          Rails.logger.info("MD5 Auth: User found with MD5 password - #{user.username}")
-
-          # Check if the provided password matches the stored MD5 password
-          if user.custom_fields['md5_password'] == Digest::MD5.hexdigest(password)
-            # Log the successful MD5 password match
-            Rails.logger.info("MD5 Auth: MD5 password match for user #{user.username}")
-
+      user = User.find_by_username_or_email(username.downcase.strip)
+      # Check if the user exists and the provided MD5 password matches the stored MD5 password
+      if user && user.custom_fields['md5_password'] == Digest::MD5.hexdigest(password)
         # Update the user to use the new password and clear the MD5 password
         user.update!(password: password)
         user.custom_fields['md5_password'] = nil
         user.save_custom_fields
-
-            # Set the current user in the environment
-            @env[CURRENT_USER_KEY] = user
-            return user
-          end
-        end
-      end
-
-      # Fallback to the original current_user method
+        user
+      else
         nil
       end
     end
-
-  # Prepend our module to the DefaultCurrentUserProvider class
-  Auth::DefaultCurrentUserProvider.prepend LegacyMd5Authentication
+  end
+
+  # Extend the DefaultCurrentUserProvider class to include our MD5 authentication logic
+  class ::Auth::DefaultCurrentUserProvider
+    prepend LegacyMd5Authentication
+
+    # Alias the original current_user method
+    alias_method :original_current_user, :current_user
+    def current_user
+      # Attempt to find the current user using the standard Discourse method
+      user = original_current_user
+      return user if user
+
+      # Check for MD5 authentication if no user is found by the standard method
+      username = @request.params[:login]
+      password = @request.params[:password]
+
+      if username && password
+        # Authenticate the user with MD5
+        user = authenticate_with_md5(username, password)
+        @env[CURRENT_USER_KEY] = user if user
+      end
+
+      user
+    end
+  end
 end