kubernetes: add node labels support

Support management of node labels through salt states.

Signed-off-by: Flavio Castelli <fcastelli@suse.com>

salt/modules/kubernetes.py

@@ -157,6 +157,89 @@ def node(name, **kwargs):
     return None
 
 
+def node_labels(name, **kwargs):
+    '''
+    Return the labels of the node identified by the specified name
+
+    CLI Examples::
+
+        salt '*' kubernetes.node_labels name="minikube"
+    '''
+    match = node(name, **kwargs)
+
+    if match is not None:
+        return match.metadata.labels
+
+    return {}
+
+
+def node_add_label(node_name, label_name, label_value, **kwargs):
+    '''
+    Set the value of the label identified by `label_name` to `label_value` on
+    the node identified by the name `node_name`.
+    Creates the lable if not present.
+
+    CLI Examples::
+
+        salt '*' kubernetes.node_add_label node_name="minikube" \
+            label_name="foo" label_value="bar"
+    '''
+    _setup_conn(**kwargs)
+    try:
+        api_instance = kubernetes.client.CoreV1Api()
+        body = {
+            'metadata': {
+                'labels': {
+                    label_name: label_value}
+                }
+        }
+        api_response = api_instance.patch_node(node_name, body)
+        return api_response
+    except (ApiException, HTTPError) as exc:
+        if isinstance(exc, ApiException) and exc.status == 404:
+            return None
+        else:
+            log.exception(
+                'Exception when calling CoreV1Api->patch_node: {0}'.format(exc)
+            )
+            raise CommandExecutionError(exc)
+
+    return None
+
+
+def node_remove_label(node_name, label_name, **kwargs):
+    '''
+    Removes the label identified by `label_name` from
+    the node identified by the name `node_name`.
+
+    CLI Examples::
+
+        salt '*' kubernetes.node_remove_label node_name="minikube" \
+            label_name="foo"
+    '''
+    _setup_conn(**kwargs)
+    try:
+        api_instance = kubernetes.client.CoreV1Api()
+        body = {
+            'metadata': {
+                'labels': {
+                    label_name: None}
+                }
+        }
+        api_response = api_instance.patch_node(node_name, body)
+        return api_response
+    except (ApiException, HTTPError) as exc:
+        if isinstance(exc, ApiException) and exc.status == 404:
+            return None
+        else:
+            log.exception(
+                'Exception when calling CoreV1Api->patch_node: {0}'.format(exc)
+            )
+            raise CommandExecutionError(exc)
+
+    return None
+
+
 def namespaces(**kwargs):
     '''
     Return the names of the available namespaces

salt/states/kubernetes.py

@@ -76,6 +76,7 @@ The kubernetes module is used to manage different kubernetes resources.
 '''
 from __future__ import absolute_import
 
+import copy
 import logging
 log = logging.getLogger(__name__)
 
@@ -831,3 +832,107 @@ def pod_present(
     }
     ret['result'] = True
     return ret
+
+
+def node_label_absent(name, node, **kwargs):
+    '''
+    Ensures that the named label is absent from the node.
+
+    name
+        The name of the label
+
+    node
+        The name of the node
+    '''
+
+    ret = {'name': name,
+           'changes': {},
+           'result': False,
+           'comment': ''}
+
+    labels = __salt__['kubernetes.node_labels'](node, **kwargs)
+
+    if name not in labels:
+        ret['result'] = True if not __opts__['test'] else None
+        ret['comment'] = 'The label does not exist'
+        return ret
+
+    if __opts__['test']:
+        ret['comment'] = 'The label is going to be deleted'
+        ret['result'] = None
+        return ret
+
+    __salt__['kubernetes.node_remove_label'](
+        node_name=node,
+        label_name=name,
+        **kwargs)
+
+    ret['result'] = True
+    ret['changes'] = {
+        'kubernetes.node_label': {
+            'new': 'absent', 'old': 'present'}}
+    ret['comment'] = 'Label removed from node'
+
+    return ret
+
+
+def node_label_present(
+        name,
+        node,
+        value,
+        **kwargs):
+    '''
+    Ensures that the named label is set on the named node
+    with the given value.
+    If the label exists it will be replaced.
+
+    name
+        The name of the label.
+
+    value
+        Value of the label.
+
+    node
+        Node to change.
+    '''
+    ret = {'name': name,
+           'changes': {},
+           'result': False,
+           'comment': ''}
+
+    labels = __salt__['kubernetes.node_labels'](node, **kwargs)
+
+    if name not in labels:
+        if __opts__['test']:
+            ret['result'] = None
+            ret['comment'] = 'The label is going to be set'
+            return ret
+        __salt__['kubernetes.node_add_label'](label_name=name,
+                                              label_value=value,
+                                              node_name=node,
+                                              **kwargs)
+    elif labels[name] == value:
+        ret['result'] = True
+        ret['comment'] = 'The label is already set and has the specified value'
+        return ret
+    else:
+        if __opts__['test']:
+            ret['result'] = None
+            return ret
+
+        ret['comment'] = 'The label is already set, changing the value'
+        __salt__['kubernetes.node_add_label'](
+            node_name=node,
+            label_name=name,
+            label_value=value,
+            **kwargs)
+
+    old_labels = copy.copy(labels)
+    labels[name] = value
+
+    ret['changes']['{0}.{1}'.format(node, name)] = {
+        'old': old_labels,
+        'new': labels}
+    ret['result'] = True
+
+    return ret