Updating Docs

Signed-off-by: David Elie-Dit-Cosaque <[email protected]>

Author: edcdavid

docs/policygenerator.md

@@ -75,3 +75,50 @@ DIRECTORY TREE              PACKAGE                 DESCRIPTION
     ├── typohelper.go       internal                Helpers for identifying manifest typos
     ├── utils.go            internal                Helper/utility functions
 ```
+## Openapi schema support 
+policy-genenerator-plugin supports openapi schemas as defined in  https://kubectl.docs.kubernetes.io/references/kustomize/kustomization/openapi by Kustomize. The goal of this feature is to support patching non kubernetest CR objects that contain list of objects.
+The openapi object in this project has the same format of the openapi object in the kustomize project. The Path indicates the relative path of the schema json file relative to the kustomization.yaml file
+``` yaml
+openapi:
+   path: schema.json
+```
+The openapi object is part of the manifest object in the plugin file:
+``` yaml
+apiVersion: policy.open-cluster-management.io/v1
+kind: PolicyGenerator
+...
+policies:
+- name: myapp
+  manifests:
+    - path: input-kustomize/
+      patches:
+      openapi:
+        path: schema.json
+```
+### How to create a Kustomize schema manually
+Ideally the openapi schema should be provided by the developper of the Custom Resource (CR).  
+To retrieve a schema from a running kubernetes cluster manually, do the following:
+
+``` default
+kustomize openapi fetch
+```
+
+Then cut and paste the subset containing the resources that need to be patched.
+
+Next, identify the list objects in the schema and select a key from the fields
+of the object that would be use to index the list, for instance a name. After
+the definition of the list, add the following text:
+
+``` default
+              "x-kubernetes-patch-merge-key": "name",
+              "x-kubernetes-patch-strategy": "merge"
+```
+
+`x-kubernetes-patch-merge-key` indicates the field in the object that is used to
+uniquely identify it in the list in this case the `name` field
+`x-kubernetes-patch-strategy` indicates the patch strategy. Merge would merge
+fields, replace would replace the object identified by the key with patch
+content.  
+`Note:` The "key" selected in this step is used in patches to uniquely identify a list object.
+  
+An example of schema for the ptp-operator PtpConfig CR is shown at [link](internal/testdata/OpenAPI/newptpconfig-schema.json)

examples/policyGenerator-kustomize.yaml

@@ -13,3 +13,8 @@ policies:
 - name: myapp
   manifests:
     - path: input-kustomize/
+      patches:
+      - metadata:
+          name: "myname"
+      openapi:
+        path: schema.json