Unable to use self.action in custom get_authenticators() method

[SpecLad]

I'd like to vary the authenticators used by a viewset depending on the current action. However, self.action is not set while get_authenticators() is executed. This is because of the following logic in ViewSetMixin.initialize_request:

django-rest-framework/rest_framework/viewsets.py

Lines 145 to 153 in 36d5c0e

	request = super().initialize_request(request, *args, **kwargs)
	method = request.method.lower()
	if method == 'options':
	# This is a special case as we always provide handling for the
	# options method in the base `View` class.
	# Unlike the other explicitly defined actions, 'metadata' is implicit.
	self.action = 'metadata'
	else:
	self.action = self.action_map.get(method)

get_authentication() is called in super().initialize_request() before self.action is assigned.

I think this could be fixed trivially by moving the super().initialize_request() call after the self.action assignment. You only need to know the request method to determine the value for self.action, which is already available before super().initialize_request(). Would you consider doing this?