More gracefully handle none selectors

Allow selection of "none" as the node selector, and handle this by
always using the cluster default instead of writing it in.

api-daemon/pvcapid/flaskapi.py

@@ -1102,7 +1102,7 @@ class API_VM_Root(Resource):
     @RequestParser([
         {'name': 'limit'},
         {'name': 'node'},
-        {'name': 'selector', 'choices': ('mem', 'vcpus', 'load', 'vms'), 'helptext': "A valid selector must be specified"},
+        {'name': 'selector', 'choices': ('mem', 'vcpus', 'load', 'vms', 'none'), 'helptext': "A valid selector must be specified"},
         {'name': 'autostart'},
         {'name': 'migration_method', 'choices': ('live', 'shutdown', 'none'), 'helptext': "A valid migration_method must be specified"},
         {'name': 'xml', 'required': True, 'helptext': "A Libvirt XML document must be specified"},
@@ -1172,7 +1172,7 @@ class API_VM_Root(Resource):
             reqargs.get('xml'),
             reqargs.get('node', None),
             reqargs.get('limit', None),
-            reqargs.get('selector', 'mem'),
+            reqargs.get('selector', 'none'),
             bool(strtobool(reqargs.get('autostart', 'false'))),
             reqargs.get('migration_method', 'none')
         )
@@ -1206,7 +1206,7 @@ class API_VM_Element(Resource):
     @RequestParser([
         {'name': 'limit'},
         {'name': 'node'},
-        {'name': 'selector', 'choices': ('mem', 'vcpus', 'load', 'vms'), 'helptext': "A valid selector must be specified"},
+        {'name': 'selector', 'choices': ('mem', 'vcpus', 'load', 'vms', 'none'), 'helptext': "A valid selector must be specified"},
         {'name': 'autostart'},
         {'name': 'migration_method', 'choices': ('live', 'shutdown', 'none'), 'helptext': "A valid migration_method must be specified"},
         {'name': 'xml', 'required': True, 'helptext': "A Libvirt XML document must be specified"},
@@ -1247,6 +1247,7 @@ class API_VM_Element(Resource):
               - vcpus
               - load
               - vms
+              - none (cluster default)
           - in: query
             name: autostart
             type: boolean
@@ -1278,7 +1279,7 @@ class API_VM_Element(Resource):
             reqargs.get('xml'),
             reqargs.get('node', None),
             reqargs.get('limit', None),
-            reqargs.get('selector', 'mem'),
+            reqargs.get('selector', 'none'),
             bool(strtobool(reqargs.get('autostart', 'false'))),
             reqargs.get('migration_method', 'none')
         )
@@ -1407,7 +1408,7 @@ class API_VM_Metadata(Resource):
 
     @RequestParser([
         {'name': 'limit'},
-        {'name': 'selector', 'choices': ('mem', 'vcpus', 'load', 'vms'), 'helptext': "A valid selector must be specified"},
+        {'name': 'selector', 'choices': ('mem', 'vcpus', 'load', 'vms', 'none'), 'helptext': "A valid selector must be specified"},
         {'name': 'autostart'},
         {'name': 'profile'},
         {'name': 'migration_method', 'choices': ('live', 'shutdown', 'none'), 'helptext': "A valid migration_method must be specified"},

api-daemon/pvcapid/helper.py

@@ -53,9 +53,6 @@ def initialize_cluster(zkhandler, overwrite=False):
         # Delete the existing keys; ignore any errors
         status = zkhandler.delete([
             '/config'
-            '/config/primary_node',
-            '/config/upstream_ip',
-            '/config/maintenance',
             '/nodes',
             '/domains',
             '/networks',
@@ -81,6 +78,7 @@ def initialize_cluster(zkhandler, overwrite=False):
         ('/config/primary_node', 'none'),
         ('/config/upstream_ip', 'none'),
         ('/config/maintenance', 'False'),
+        ('/config/migration_target_selector', 'none'),
         ('/nodes', ''),
         ('/domains', ''),
         ('/networks', ''),

api-daemon/pvcapid/provisioner.py

@@ -219,6 +219,9 @@ def create_template_system(name, vcpu_count, vram_mb, serial=False, vnc=False, v
         retcode = 400
         return retmsg, retcode
 
+    if node_selector == 'none':
+        node_selector = None
+
     query = "INSERT INTO system_template (name, vcpu_count, vram_mb, serial, vnc, vnc_bind, node_limit, node_selector, node_autostart, migration_method, ova) VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s);"
     args = (name, vcpu_count, vram_mb, serial, vnc, vnc_bind, node_limit, node_selector, node_autostart, migration_method, ova)
 
@@ -414,6 +417,9 @@ def modify_template_system(name, vcpu_count=None, vram_mb=None, serial=None, vnc
         fields.append({'field': 'node_limit', 'data': node_limit})
 
     if node_selector is not None:
+        if node_selector == 'none':
+            node_selector = 'None'
+
         fields.append({'field': 'node_selector', 'data': node_selector})
 
     if node_autostart is not None:

client-cli/pvc.py

@@ -618,8 +618,8 @@ def cli_vm():
 )
 @click.option(
     '-s', '--selector', 'node_selector', default='mem', show_default=True,
-    type=click.Choice(['mem', 'load', 'vcpus', 'vms']),
+    type=click.Choice(['mem', 'load', 'vcpus', 'vms', 'none']),
-    help='Method to determine optimal target node during autoselect; saved with VM.'
+    help='Method to determine optimal target node during autoselect; "none" will use the default for the cluster.'
 )
 @click.option(
     '-a/-A', '--autostart/--no-autostart', 'node_autostart', is_flag=True, default=False,
@@ -664,8 +664,8 @@ def vm_define(vmconfig, target_node, node_limit, node_selector, node_autostart,
 )
 @click.option(
     '-s', '--selector', 'node_selector', default=None, show_default=False,
-    type=click.Choice(['mem', 'load', 'vcpus', 'vms']),
+    type=click.Choice(['mem', 'load', 'vcpus', 'vms', 'none']),
-    help='Method to determine optimal target node during autoselect.'
+    help='Method to determine optimal target node during autoselect; "none" will use the default for the cluster.'
 )
 @click.option(
     '-a/-A', '--autostart/--no-autostart', 'node_autostart', is_flag=True, default=None,
@@ -2895,9 +2895,9 @@ def provisioner_template_system_list(limit):
 )
 @click.option(
     '--node-selector', 'node_selector',
-    type=click.Choice(['mem', 'vcpus', 'vms', 'load'], case_sensitive=False),
+    type=click.Choice(['mem', 'vcpus', 'vms', 'load', 'none'], case_sensitive=False),
-    default=None,  # Use cluster default
+    default='none',
-    help='Use this selector to determine the optimal node during migrations.'
+    help='Method to determine optimal target node during autoselect; "none" will use the default for the cluster.'
 )
 @click.option(
     '--node-autostart', 'node_autostart',
@@ -2973,8 +2973,8 @@ def provisioner_template_system_add(name, vcpus, vram, serial, vnc, vnc_bind, no
 )
 @click.option(
     '--node-selector', 'node_selector',
-    type=click.Choice(['mem', 'vcpus', 'vms', 'load'], case_sensitive=False),
+    type=click.Choice(['mem', 'vcpus', 'vms', 'load', 'none'], case_sensitive=False),
-    help='Use this selector to determine the optimal node during migrations.'
+    help='Method to determine optimal target node during autoselect; "none" will use the default for the cluster.'
 )
 @click.option(
     '--node-autostart', 'node_autostart',

daemon-common/common.py

@@ -430,7 +430,11 @@ def findTargetNode(zkhandler, dom_uuid):
     try:
         search_field = zkhandler.read('/domains/{}/node_selector'.format(dom_uuid))
     except Exception:
-        search_field = 'mem'
+        search_field = None
+
+    # If our search field is invalid, use the default
+    if search_field is None or search_field == 'None':
+        search_field = zkhandler.read('/config/migration_target_selector')
 
     # Execute the search
     if search_field == 'mem':

node-daemon/pvcnoded/common.py

@@ -160,10 +160,9 @@ def findTargetNode(zk_conn, config, logger, dom_uuid):
     except Exception:
         search_field = None
 
-    # If our search field is invalid, use and set the default (for next time)
+    # If our search field is invalid, use the default
     if search_field is None or search_field == 'None':
-        search_field = config['migration_target_selector']
+        search_field = zkhandler.readdata(zk_conn, '/config/migration_target_selector')
-        zkhandler.writedata(zk_conn, {'/domains/{}/node_selector'.format(dom_uuid): config['migration_target_selector']})
 
     if config['debug']:
         logger.out('Migrating VM {} with selector {}'.format(dom_uuid, search_field), state='d', prefix='node-flush')