k8s support diff mode (#146)

* support diff mode for k8s module

* Update and rename 145-k8s-add-support-diff-mode.yml to 146-k8s-add-support-diff-mode.yml

* Update 146-k8s-add-support-diff-mode.yml

* Update changelogs/fragments/146-k8s-add-support-diff-mode.yml

Co-authored-by: Mike Graves <mgraves@redhat.com>

* update k8s_scale and k8s_json_patch

* diff for k8s_scale  and k8s_json_patch

Co-authored-by: Mike Graves <mgraves@redhat.com>

changelogs/fragments/146-k8s-add-support-diff-mode.yml

@@ -0,0 +1,2 @@
+bugfixes:
+  - k8s - Fixes a bug where diff was always returned when using apply or modifying an existing object, even when diff=no was specified. The module no longer returns diff unless requested and will now honor diff=no (https://github.com/ansible-collections/kubernetes.core/pull/146).

molecule/default/converge.yml

@@ -164,6 +164,14 @@
       tags:
         - always
 
+    - name: Include diff.yml
+      include_tasks:
+        file: tasks/diff.yml
+        apply:
+          tags: [ diff, k8s ]
+      tags:
+        - always
+
   roles:
     - role: helm
       tags:

molecule/default/tasks/diff.yml

@@ -0,0 +1,153 @@
+---
+- set_fact:
+    diff_namespace: "diff"
+    diff_configmap: "diff-configmap"
+
+- block:
+  - name: Ensure namespace
+    k8s:
+      kind: Namespace
+      name: '{{ diff_namespace }}'
+
+  # Using option 'apply' set to 'yes'
+  - name: Create Pod using apply and diff set to yes
+    k8s:
+      namespace: '{{ diff_namespace }}'
+      apply: yes
+      template: "pod_diff.j2"
+    diff: yes
+    vars:
+      pod_name: "pod-apply"
+      pod_image: "busybox:1.32.0"
+    register: result
+
+  - name: check that result has diff attribute
+    assert:
+      that:
+      - result is changed
+      - result.diff is defined
+
+  - name: Update pod definition using apply and diff set to no
+    k8s:
+      namespace: '{{ diff_namespace }}'
+      apply: yes
+      template: "pod_diff.j2"
+    diff: no
+    vars:
+      pod_name: "pod-apply"
+      pod_image: "busybox:1.33.0"
+    register: result
+
+  - name: check that output has no diff attribute
+    assert:
+      that:
+      - result is changed
+      - result.diff is not defined
+
+  # Using option 'state=patched'
+  - name: Create Pod using state=present and diff set to yes
+    k8s:
+      namespace: '{{ diff_namespace }}'
+      state: present
+      template: "pod_diff.j2"
+    vars:
+      pod_name: "pod-patch"
+      pod_image: "busybox:1.32.0"
+    register: result
+
+  - name: Update pod definition using state=patched
+    k8s:
+      namespace: '{{ diff_namespace }}'
+      state: patched
+      template: "pod_diff.j2"
+    diff: no
+    vars:
+      pod_name: "pod-patch"
+      pod_image: "busybox:1.33.0"
+      pod_label: "patching"
+    register: result
+
+  - name: check that output has no diff attribute
+    assert:
+      that:
+      - result is changed
+      - result.diff is not defined
+
+  - name: Update pod definition using state=patched and diff=yes
+    k8s:
+      namespace: '{{ diff_namespace }}'
+      state: patched
+      template: "pod_diff.j2"
+    diff: yes
+    vars:
+      pod_name: "pod-patch"
+      pod_image: "busybox:1.33.0"
+      pod_label: "running"
+    register: result
+
+  - name: check that output has no diff attribute
+    assert:
+      that:
+      - result is changed
+      - result.diff is defined
+
+  # check diff mode using force=yes
+  - name: Create a ConfigMap
+    k8s:
+      kind: ConfigMap
+      name: '{{ diff_configmap }}'
+      namespace: '{{ diff_namespace }}'
+      definition:
+        data:
+          key: "initial value"
+    diff: yes
+    register: result
+
+  - name: check that output has no diff attribute
+    assert:
+      that:
+      - result is changed
+      - result.diff is not defined
+
+  - name: Update ConfigMap using force and diff=no
+    k8s:
+      kind: ConfigMap
+      name: '{{ diff_configmap }}'
+      namespace: '{{ diff_namespace }}'
+      force: yes
+      definition:
+        data:
+          key: "update value with diff=no"
+    diff: no
+    register: result
+
+  - name: check that output has no diff attribute
+    assert:
+      that:
+      - result is changed
+      - result.diff is not defined
+
+  - name: Update ConfigMap using force and diff=yes
+    k8s:
+      kind: ConfigMap
+      name: '{{ diff_configmap }}'
+      namespace: '{{ diff_namespace }}'
+      force: yes
+      definition:
+        data:
+          key: "update value with diff=yes"
+    diff: yes
+    register: result
+
+  - name: check that output has diff attribute
+    assert:
+      that:
+      - result is changed
+      - result.diff is defined
+
+  always:
+  - name: Ensure namespace is deleted
+    k8s:
+      state: absent
+      kind: Namespace
+      name: '{{ diff_namespace }}'

molecule/default/tasks/json_patch.yml

@@ -43,13 +43,15 @@
             value: busybox:glibc
       check_mode: yes
       register: result
+      diff: yes
 
     - name: Assert patch was made
       assert:
         that:
           - result.changed
           - result.result.metadata.labels.label2 == "bar"
           - result.result.spec.containers[0].image == "busybox:glibc"
+          - result.diff
 
     - name: Describe pod
       kubernetes.core.k8s_info:
@@ -82,6 +84,7 @@
       assert:
         that:
           - result.changed
+          - result.diff is not defined
 
     - name: Describe pod
       kubernetes.core.k8s_info:

molecule/default/tasks/scale.yml

@@ -54,6 +54,7 @@
         replicas: 0
         wait: yes
       register: scale_down
+      diff: true
 
     - name: Get pods in scale-deploy
       k8s_info:
@@ -143,7 +144,7 @@
         that:
           - scale_up is changed
           - '"duration" in scale_up'
-          - scale_up.diff
+          - scale_up.diff is not defined
           - scale_up_further_deploy_pods.resources | length == 2
 
     - name: Don't scale the deployment up
@@ -170,7 +171,7 @@
       assert:
         that:
           - scale_up_noop is not changed
-          - not scale_up_noop.diff
+          - scale_up_noop.diff is not defined
           - scale_up_noop_pods.resources | length == 2
           - '"duration" in scale_up_noop'
 
@@ -183,6 +184,7 @@
         replicas: 1
         wait: no
       register: scale_down_no_wait
+      diff: true
 
     - name: Ensure that scale down succeeds
       k8s_info:

molecule/default/templates/pod_diff.j2

@@ -0,0 +1,14 @@
+apiVersion: v1
+kind: Pod
+metadata:
+    name: {{ pod_name }}
+    labels:
+        ansible: {{ pod_label | default('demo') }}
+spec:
+    containers:
+    - name: c0
+      image: {{ pod_image }}
+      command:
+        - /bin/sh
+        - -c
+        - while true;do date;sleep 5; done

plugins/module_utils/common.py

@@ -693,7 +693,8 @@ def build_error_msg(kind, name, msg):
                     existing = {}
                 match, diffs = self.diff_objects(existing, result['result'])
                 result['changed'] = not match
-                result['diff'] = diffs
+                if self.module._diff:
+                    result['diff'] = diffs
                 result['method'] = 'apply'
                 if not success:
                     msg = "Resource apply timed out"
@@ -785,7 +786,8 @@ def build_error_msg(kind, name, msg):
                 match, diffs = self.diff_objects(existing.to_dict(), result['result'])
                 result['changed'] = not match
                 result['method'] = 'replace'
-                result['diff'] = diffs
+                if self.module._diff:
+                    result['diff'] = diffs
                 if not success:
                     msg = "Resource replacement timed out"
                     if continue_on_error:
@@ -819,7 +821,8 @@ def build_error_msg(kind, name, msg):
             match, diffs = self.diff_objects(existing.to_dict(), result['result'])
             result['changed'] = not match
             result['method'] = 'patch'
-            result['diff'] = diffs
+            if self.module._diff:
+                result['diff'] = diffs
 
             if not success:
                 msg = "Resource update timed out"

plugins/modules/k8s_json_patch.py

@@ -254,7 +254,8 @@ def build_error_msg(kind, name, msg):
         success, result['result'], result['duration'] = k8s_module.wait(resource, definition, wait_sleep, wait_timeout, condition=wait_condition)
     match, diffs = k8s_module.diff_objects(existing.to_dict(), obj)
     result["changed"] = not match
-    result["diff"] = diffs
+    if module._diff:
+        result["diff"] = diffs
 
     if not success:
         msg = "Resource update timed out"

plugins/modules/k8s_scale.py

@@ -181,7 +181,9 @@ def execute_module(module, k8s_ansible_mixin,):
     wait_sleep = module.params.get('wait_sleep')
     existing = None
     existing_count = None
-    return_attributes = dict(result=dict(), diff=dict())
+    return_attributes = dict(result=dict())
+    if module._diff:
+        return_attributes['diff'] = dict()
     if wait:
         return_attributes['duration'] = 0
 
@@ -256,7 +258,9 @@ def _continue_or_exit(warn):
             name = existing.metadata.name
             namespace = existing.metadata.namespace
             existing = resource.get(name=name, namespace=namespace)
-            result = {'changed': False, 'result': existing.to_dict(), 'diff': {}}
+            result = {'changed': False, 'result': existing.to_dict()}
+            if module._diff:
+                result['diff'] = {}
             if wait:
                 result['duration'] = 0
         # append result to the return attribute
@@ -302,7 +306,8 @@ def scale(module, k8s_ansible_mixin, resource, existing_object, replicas, wait,
     result = dict()
     result['result'] = k8s_obj
     result['changed'] = not match
-    result['diff'] = diffs
+    if module._diff:
+        result['diff'] = diffs
 
     if wait:
         success, result['result'], result['duration'] = k8s_ansible_mixin.wait(resource, scale_obj, wait_sleep, wait_time)