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>

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

@@ -43,6 +43,7 @@
             value: busybox:glibc
       check_mode: yes
       register: result
+      diff: yes
 
     - name: Assert patch was made
       assert:
@@ -50,6 +51,7 @@
           - 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: