Clear the extension requirement

Change-Id: If0725e009dfb98fe949b9e00349108c88cf4424a
Closes-bug: #1486845

1 files changed, 39 insertions, 11 deletions

diff --git a/doc/source/devref/client_command_extensions.rst b/doc/source/devref/client_command_extensions.rst
index 10d39d8..b89078e 100644
--- a/doc/source/devref/client_command_extensions.rst
+++ b/doc/source/devref/client_command_extensions.rst
@@ -12,18 +12,45 @@ neutronclient/neutron/v2_0/contrib/_fox_sockets.py
 Minimum requirements from an extension
 --------------------------------------
 
-* Will have a class that subclasses NeutronClientExtension to provide the
-  requisite version support, paths, and variable names for the client.
-  Example: neutronclient.neutron.v2_0.contrib._fox_sockets.FoxInSocket
+* NeutronClientExtension subclasses must have a shell_command class variable
+  if the command is to be available to the CLI (shell.py)
 
-* Will have at least one class that subclasses from the ClientExtension
-  classes to provide the new functionality to the client
   Example: neutronclient.neutron.v2_0.contrib._fox_sockets.FoxInSocketsList
 
-* ClientExtension subclasses must have a shell_command class variable if the
-  command is to be available to the CLI (shell.py)
+Minimum requirements to use canonical neutron CRUD commands framework
+----------------------------------------------------------------------
+
+Neutron commands are cliff commands, commands in extension can use their
+own way to finish their tasks. But if they want to make use of the canonical
+neutron CRUD commands framework, the extension should:
+
+* have a class that subclasses NeutronClientExtension to provide the
+  requisite resource name, version support, and resource collection and
+  object paths for a resource the commands will process.
+
+  Example: neutronclient.neutron.v2_0.contrib._fox_sockets.FoxInSocket
+
+* have a class that subclasses from the ClientExtensionList to provide
+  resource object list function. This is because most commands
+  need the list function to get object ID via
+  neutronclient.neutron.v2_0.__init__.find_resource_by_id.
+
   Example: neutronclient.neutron.v2_0.contrib._fox_sockets.FoxInSocketsList
 
+* if needed, subclass ClientExtensionUpdate to implement update of the resource
+  object.
+
+  Example: neutronclient.neutron.v2_0.contrib._fox_sockets.FoxInSocketsUpdate
+
+* if needed, subclass ClientExtensionDelete to implement deletion of the resource
+  object.
+
+  Example: neutronclient.neutron.v2_0.contrib._fox_sockets.FoxInSocketsDelete
+
+* if needed, subclass ClientExtensionShow to get the detail of the resource
+  object.
+
+  Example: neutronclient.neutron.v2_0.contrib._fox_sockets.FoxInSocketsShow
 
 Precedence of command loading
 ------------------------------
@@ -40,8 +67,9 @@ Parent/child relationships may be added if desired.
 
 neutronclient.extension entry_point
 -----------------------------------
+
 To activate the commands in a specific extension module, add an entry in
-setup.cfg under neutronclient.extension. For example:
-[entry_points]
-neutronclient.extension =
-    fox_sockets = neutronclient.neutron.v2_0.contrib._fox_sockets
\ No newline at end of file
+setup.cfg under neutronclient.extension. For example::
+  [entry_points]
+  neutronclient.extension =
+      fox_sockets = neutronclient.neutron.v2_0.contrib._fox_sockets