Merge pull request #2591 from MGatner/auth-rec

User Guide authentication recommendations

Author: lonnieezell

user_guide_src/source/extending/authentication.rst

@@ -0,0 +1,13 @@
+Authentication 
+#####################################
+
+CodeIgniter intentionally does not provide an internal authentication or authorization class. There are a number
+of great third-party modules that provide these services, as well as resources in the community for writing
+your own. The following are recommended guidelines to encourage consistency among developers of
+modules, projects, and the framework itself.
+
+Recommendations
+===============
+
+* Modules that handle login and logout operations should trigger the ``login`` and ``logout`` Events when successful
+* Modules that define a "current user" should define the function ``user_id()`` to return the user's unique identifier, or ``null`` for "no current user"

user_guide_src/source/extending/index.rst

@@ -11,4 +11,5 @@ CodeIgniter 4 has been designed to be easy to extend or build upon.
     common
     events
     basecontroller
+    authentication
     contributing