k8s - add support for Server Side apply (#260)

k8s - add support for Server Side apply

SUMMARY

Server side apply is now support for k8s module with this Pull request.
The feature is not yet released on kubernetes-client, once this is done, we can merge this pull request.
closes #87

ISSUE TYPE


Feature Pull Request

COMPONENT NAME

k8s
ADDITIONAL INFORMATION

Reviewed-by: Mike Graves <mgraves@redhat.com>
Reviewed-by: None <None>
Reviewed-by: None <None>

changelogs/fragments/260-k8s-add-support-for-server_side_apply.yml

@@ -0,0 +1,2 @@
+minor_changes:
+  - k8s - add support for server_side_apply. (https://github.com/ansible-collections/kubernetes.core/issues/87).

molecule/default/tasks/apply.yml

@@ -896,6 +896,139 @@
         that:
           - k8s_networkpolicy is not changed
 
+    # Server Side Apply
+    - name: Create Configmap using server side apply - field_manager not specified
+      k8s:
+        namespace: "{{ apply_namespace }}"
+        definition:
+          apiVersion: v1
+          kind: ConfigMap
+          metadata:
+            name: server-side-cm
+          data:
+            key: value-0
+        apply: yes
+        server_side_apply:
+          force_conflicts: false
+      register: result
+      ignore_errors: true
+
+    - name: Check that configmap creation failed
+      assert:
+        that:
+          - result is failed
+          - '"field_manager" in result.msg'
+
+    - name: Create Configmap using server side apply
+      k8s:
+        namespace: "{{ apply_namespace }}"
+        definition:
+          apiVersion: v1
+          kind: ConfigMap
+          metadata:
+            name: server-side-cm
+          data:
+            key: value-0
+        apply: yes
+        server_side_apply:
+          field_manager: "manager-00"
+      register: result
+
+    - name: Check configmap was created with expected manager
+      assert:
+        that:
+          - result is changed
+          - result.result.metadata.managedFields | length == 1
+          - result.result.metadata.managedFields[0].manager == 'manager-00'
+
+    - name: Apply ConfigMap using same parameters
+      k8s:
+        namespace: "{{ apply_namespace }}"
+        definition:
+          apiVersion: v1
+          kind: ConfigMap
+          metadata:
+            name: server-side-cm
+          data:
+            key: value-0
+        apply: yes
+        server_side_apply:
+          field_manager: "manager-00"
+      register: result
+
+    - name: Assert that nothing change using check_mode
+      assert:
+        that:
+          - result is not changed
+
+    - name: Apply ConfigMap adding new manager
+      k8s:
+        namespace: "{{ apply_namespace }}"
+        definition:
+          apiVersion: v1
+          kind: ConfigMap
+          metadata:
+            name: server-side-cm
+          data:
+            key: value-0
+        apply: yes
+        server_side_apply:
+          field_manager: "manager-01"
+      register: result
+
+    - name: Assert that number of manager has increased
+      assert:
+        that:
+          - result is changed
+          - result.result.metadata.managedFields | length == 2
+
+    - name: Apply changes to Configmap using new field_manager
+      k8s:
+        namespace: "{{ apply_namespace }}"
+        definition:
+          apiVersion: v1
+          kind: ConfigMap
+          metadata:
+            name: server-side-cm
+          data:
+            key: value-1
+        apply: yes
+        server_side_apply:
+          field_manager: "manager-02"
+      register: result
+      ignore_errors: true
+
+    - name: assert that operation failed with conflicts
+      assert:
+        that:
+          - result is failed
+          - result.reason == 'Conflict'
+
+    - name: Apply changes to Configmap using new field_manager and force_conflicts
+      k8s:
+        namespace: "{{ apply_namespace }}"
+        definition:
+          apiVersion: v1
+          kind: ConfigMap
+          metadata:
+            name: server-side-cm
+          data:
+            key: value-1
+        apply: yes
+        server_side_apply:
+          field_manager: "manager-02"
+          force_conflicts: true
+      register: result
+
+    - name: assert that operation failed with conflicts
+      assert:
+        that:
+          - result is changed
+          - result.result.metadata.managedFields | length == 1
+          - result.result.metadata.managedFields[0].manager == 'manager-02'
+          - result.result.data.key == 'value-1'
+
+
   always:
     - name: Remove namespace
       k8s:

plugins/module_utils/apply.py

@@ -114,12 +114,14 @@ def apply_patch(actual, desired):
         return actual, dict_merge(desired, annotate(desired))
 
 
-def apply_object(resource, definition):
+def apply_object(resource, definition, server_side=False):
     try:
         actual = resource.get(
             name=definition["metadata"]["name"],
             namespace=definition["metadata"].get("namespace"),
         )
+        if server_side:
+            return actual, None
     except NotFoundError:
         return None, dict_merge(definition, annotate(definition))
     return apply_patch(actual.to_dict(), definition)
@@ -127,6 +129,17 @@ def apply_object(resource, definition):
 
 def k8s_apply(resource, definition, **kwargs):
     existing, desired = apply_object(resource, definition)
+    server_side = kwargs.get("server_side", False)
+    if server_side:
+        body = json.dumps(definition).encode()
+        # server_side_apply is forces content_type to 'application/apply-patch+yaml'
+        return resource.server_side_apply(
+            body=body,
+            name=definition["metadata"]["name"],
+            namespace=definition["metadata"].get("namespace"),
+            force_conflicts=kwargs.get("force_conflicts"),
+            field_manager=kwargs.get("field_manager"),
+        )
     if not existing:
         return resource.create(
             body=desired, namespace=definition["metadata"].get("namespace"), **kwargs

plugins/module_utils/common.py

@@ -490,7 +490,7 @@ class K8sAnsibleMixin(object):
                         self.params.pop(alias)
 
     def load_resource_definitions(self, src):
-        """ Load the requested src path """
+        """Load the requested src path"""
         result = None
         path = os.path.normpath(src)
         if not os.path.exists(path):
@@ -834,6 +834,7 @@ class K8sAnsibleMixin(object):
         wait_condition = None
         continue_on_error = self.params.get("continue_on_error")
         label_selectors = self.params.get("label_selectors")
+        server_side_apply = self.params.get("server_side_apply")
         if self.params.get("wait_condition") and self.params["wait_condition"].get(
             "type"
         ):
@@ -1028,6 +1029,7 @@ class K8sAnsibleMixin(object):
                             namespace=namespace,
                         )
                     )
+
                     return result
             if apply:
                 if self.check_mode and not self.supports_dry_run:
@@ -1043,6 +1045,24 @@ class K8sAnsibleMixin(object):
                         params = {}
                         if self.check_mode:
                             params["dry_run"] = "All"
+                        if server_side_apply:
+                            params["server_side"] = True
+                            if LooseVersion(kubernetes.__version__) < LooseVersion(
+                                "19.15.0"
+                            ):
+                                msg = "kubernetes >= 19.15.0 is required to use server side apply."
+                                if continue_on_error:
+                                    result["error"] = dict(msg=msg)
+                                    return result
+                                else:
+                                    self.fail_json(
+                                        msg=msg, version=kubernetes.__version__
+                                    )
+                            if not server_side_apply.get("field_manager"):
+                                self.fail(
+                                    msg="field_manager is required to use server side apply."
+                                )
+                            params.update(server_side_apply)
                         k8s_obj = resource.apply(
                             definition, namespace=namespace, **params
                         ).to_dict()

plugins/modules/k8s.py

@@ -152,6 +152,26 @@ options:
     - mutually exclusive with C(name).
     type: str
     version_added: 2.3.0
+  server_side_apply:
+    description:
+    - When this option is set, apply runs in the server instead of the client.
+    - Ignored if C(apply) is not set or is set to False.
+    - This option requires "kubernetes >= 19.15.0".
+    type: dict
+    version_added: 2.3.0
+    suboptions:
+      field_manager:
+        type: str
+        description:
+        - Name of the manager used to track field ownership.
+        required: True
+      force_conflicts:
+        description:
+        - A conflict is a special status error that occurs when an Server Side Apply operation tries to change a field,
+          which another user also claims to manage.
+        - When set to True, server-side apply will force the changes against conflicts.
+        type: bool
+        default: False
 
 requirements:
   - "python >= 3.6"
@@ -302,6 +322,19 @@ EXAMPLES = r"""
         - name: py
           image: python:3.7-alpine
           imagePullPolicy: IfNotPresent
+
+# Server side apply
+- name: Create configmap using server side apply
+  kubernetes.core.k8s:
+    namespace: testing
+    definition:
+      apiVersion: v1
+      kind: ConfigMap
+      metadata:
+        name: my-configmap
+    apply: yes
+    server_side_apply:
+      field_manager: ansible
 """
 
 RETURN = r"""
@@ -368,6 +401,13 @@ def validate_spec():
     )
 
 
+def server_apply_spec():
+    return dict(
+        field_manager=dict(type="str", required=True),
+        force_conflicts=dict(type="bool", default=False),
+    )
+
+
 def argspec():
     argument_spec = copy.deepcopy(NAME_ARG_SPEC)
     argument_spec.update(copy.deepcopy(RESOURCE_ARG_SPEC))
@@ -390,6 +430,9 @@ def argspec():
     argument_spec["force"] = dict(type="bool", default=False)
     argument_spec["label_selectors"] = dict(type="list", elements="str")
     argument_spec["generate_name"] = dict()
+    argument_spec["server_side_apply"] = dict(
+        type="dict", default=None, options=server_apply_spec()
+    )
 
     return argument_spec