Add user manager factory hook

docs/modules/index.rst

@@ -14,4 +14,5 @@ Internal Modules
    server.rst
    settings.rst
    slicing.rst
+   users.rst
    util.rst

docs/modules/users.rst

@@ -0,0 +1,9 @@
+.. _sec-modules-users:
+
+octoprint.users
+---------------
+
+.. automodule:: octoprint.users
+   :members:
+
+

docs/plugins/hooks.rst

@@ -946,3 +946,38 @@ octoprint.ui.web.templatetypes
    :param dict template_sorting: read-only dictionary of currently configured template sorting specifications
    :return: a list of 3-tuples (template type, rule, sorting spec)
    :rtype: list
+
+.. _sec-plugins-hook-users-factory:
+
+octoprint.users.factory
+~~~~~~~~~~~~~~~~~~~~~~~
+
+.. py:function:: user_manager_factory_hook(components, settings, *args, **kwargs)
+
+   Return a :class:`~octoprint.users.UserManager` instance to use as global user manager object. This will
+   be called only once during initial server startup.
+
+   The provided ``components`` is a dictionary containing the already initialized system components:
+
+     * ``plugin_manager``: The :class:`~octoprint.plugin.core.PluginManager`
+     * ``printer_profile_manager``: The :class:`~octoprint.printer.profile.PrinterProfileManager`
+     * ``event_bus``: The :class:`~octoprint.events.EventManager`
+     * ``analysis_queue``: The :class:`~octoprint.filemanager.analysis.AnalysisQueue`
+     * ``slicing_manager``: The :class:`~octoprint.slicing.SlicingManager`
+     * ``file_manager``: The :class:`~octoprint.filemanager.FileManager`
+     * ``app_session_manager``: The :class:`~octoprint.server.util.flask.AppSessionManager`
+     * ``plugin_lifecycle_manager``: The :class:`~octoprint.server.LifecycleManager`
+     * ``preemptive_cache``: The :class:`~octoprint.server.util.flask.PreemptiveCache`
+
+   If the factory returns anything but ``None``, it will be assigned to the global ``userManager`` instance.
+
+   If no of the registered factories return a user manager instance, the class referenced by the ``config.yaml``
+   entry ``accessControl.userManager`` will be initialized if possible, otherwise a stock
+   :class:`~octoprint.users.FilebasedUserManager` will be instantiated, linked to the default user storage
+   file ``~/.octoprint/users.yaml``.
+
+   :param dict components: System components to use for user manager instance initialization
+   :param SettingsManager settings: The global settings manager instance to fetch configuration values from if necessary
+   :return: The ``userManager`` instance to use globally.
+   :rtype: UserManager subclass or None
+

src/octoprint/server/__init__.py

@@ -284,11 +284,33 @@ class Server(object):
 			file_manager=fileManager,
 			app_session_manager=appSessionManager,
 			plugin_lifecycle_manager=pluginLifecycleManager,
-			user_manager=userManager,
 			preemptive_cache=preemptiveCache,
 			connectivity_checker=connectivityChecker
 		)
 
+		# create user manager instance
+		user_manager_factories = pluginManager.get_hooks("octoprint.users.factory")
+		for name, factory in user_manager_factories.items():
+			try:
+				userManager = factory(components, self._settings)
+				if userManager is not None:
+					self._logger.debug("Created user manager instance from factory {}".format(name))
+					break
+			except:
+				self._logger.exception("Error while creating user manager instance from factory {}".format(name))
+		else:
+			name = self._settings.get(["accessControl", "userManager"])
+			try:
+				clazz = octoprint.util.get_class(name)
+				userManager = clazz()
+			except:
+				self._logger.exception(
+					"Could not instantiate user manager {}, falling back to FilebasedUserManager!".format(name))
+				userManager = octoprint.users.FilebasedUserManager()
+			finally:
+				userManager.enabled = self._settings.getBoolean(["accessControl", "enabled"])
+		components.update(dict(user_manager=userManager))
+
 		# create printer instance
 		printer_factories = pluginManager.get_hooks("octoprint.printer.factory")
 		for name, factory in printer_factories.items():