Only show available share protocols on share creation modal

Do not show share protocols in Shares drop-down menu if
the backend is not available.
This patch set is a workaround for this bug. We are using the
settings override feature. Operators will need to place a
'enabled_share_protocols: ['proto1', 'proto2', ...]' setting
on the OPENSTACK_MANILA_SETTINGS files.
The correct fix for this bug would be to add a capabilities
endpoint in the controller plane in order to get the available
backends.

Change-Id: I13637491994e6f074e66fe0f3026a303944892ec
Closes-Bug: #1622732

README.rst

@@ -96,6 +96,21 @@ where you can redefine the values of the OPENSTACK_MANILA_FEATURES dict::
     * enable_replication
     * enable_migration
     * enable_public_share_type_creation
+    * enabled_share_protocols
+
+By default, enabled_share_protocols within the OPENSTACK_MANILA_FEATURES
+dict contains a list with all the supported protocols. The operator can
+change this to display to users only those protocols that has been deployed
+and are available to use. E.g. if only NFS is available, the operator is
+expected to redefine enabled_share_protocols as follows:
+
+.. code-block:: python
+
+    OPENSTACK_MANILA_FEATURES = {
+       'enable_replication': True,
+       'enable_migration': True,
+       'enabled_share_protocols': ['NFS'],
+    }
 
 Contributing
 ------------

manila_ui/dashboards/admin/shares/forms.py

@@ -200,10 +200,9 @@ class ManageShare(forms.SelfHandlingForm):
         max_length=255, label=_("Export location"), required=True,
         help_text=_("Export location of share. Example for NFS: "
                     "1.2.3.4:/path/to/share"))
-    protocol = forms.ChoiceField(
-        label=_("Share Protocol"), required=True,
-        choices=(('NFS', 'NFS'), ('CIFS', 'CIFS'), ('GlusterFS', 'GlusterFS'),
-                 ('HDFS', 'HDFS'), ('CephFS', 'CephFS')))
+
+    protocol = forms.ChoiceField(label=_("Share Protocol"), required=True)
+
     share_type = forms.ChoiceField(label=_("Share Type"), required=True)
 
     driver_options = forms.CharField(
@@ -228,6 +227,17 @@ class ManageShare(forms.SelfHandlingForm):
             if dhss and dhss.lower() in strutils.FALSE_STRINGS:
                 st_choices.append((st.name, st.name))
         self.fields['share_type'].choices = st_choices
+        # NOTE(vkmc): choose only those share protocols that are enabled
+        # FIXME(vkmc): this should be better implemented by having a
+        # capabilities endpoint on the control plane.
+        manila_features = getattr(settings, 'OPENSTACK_MANILA_FEATURES', {})
+        self.enabled_share_protocols = manila_features.get(
+            'enabled_share_protocols',
+            ['NFS', 'CIFS', 'GlusterFS', 'HDFS', 'CephFS'])
+        self.fields['protocol'].choices = ([(' ', ' ')] +
+                                           [(enabled_proto, enabled_proto)
+                                           for enabled_proto in
+                                           self.enabled_share_protocols])
 
     def handle(self, request, data):
         try:

manila_ui/dashboards/project/shares/shares/forms.py

@@ -47,10 +47,15 @@ class CreateForm(forms.SelfHandlingForm):
 
     def __init__(self, request, *args, **kwargs):
         super(CreateForm, self).__init__(request, *args, **kwargs)
+        # NOTE(vkmc): choose only those share protocols that are enabled
+        # FIXME(vkmc): this should be better implemented by having a
+        # capabilities endpoint on the control plane.
         manila_features = getattr(settings, 'OPENSTACK_MANILA_FEATURES', {})
+        self.enabled_share_protocols = manila_features.get(
+            'enabled_share_protocols',
+            ['NFS', 'CIFS', 'GlusterFS', 'HDFS', 'CephFS'])
         self.enable_public_shares = manila_features.get(
             'enable_public_shares', True)
-        share_protos = ('NFS', 'CIFS', 'GlusterFS', 'HDFS', 'CephFS')
         share_networks = manila.share_network_list(request)
         share_types = manila.share_type_list(request)
         self.fields['share_type'].choices = (
@@ -105,7 +110,8 @@ class CreateForm(forms.SelfHandlingForm):
                 help_text=(
                     "If set then all tenants will be able to see this share."))
 
-        self.fields['share_proto'].choices = [(sp, sp) for sp in share_protos]
+        self.fields['share_proto'].choices = [(sp, sp) for sp in
+                                              self.enabled_share_protocols]
         if "snapshot_id" in request.GET:
             try:
                 snapshot = self.get_snapshot(request,

manila_ui/local/local_settings.d/_90_manila_shares.py

@@ -17,4 +17,5 @@
 OPENSTACK_MANILA_FEATURES = {
     'enable_replication': True,
     'enable_migration': True,
+    'enabled_share_protocols': ['NFS', 'CIFS', 'GlusterFS', 'HDFS', 'CephFS'],
 }