Allow exec and function transformers to generate resources

plugin/someteam.example.com/v1/starlarkmixer/StarlarkMixer_test.go

@@ -38,12 +38,24 @@ data:
 kind: ConfigMap
 metadata:
   annotations:
+    config.kubernetes.io/path: configmap_some-cm.yaml
     modified-by: mixer-instance
   name: some-cm
 ---
 apiVersion: v1
+data:
+  foo: bar
 kind: ConfigMap
 metadata:
+  annotations:
+    config.kubernetes.io/path: configmap_some-cm-copy.yaml
+  name: some-cm-copy
+---
+apiVersion: v1
+kind: ConfigMap
+metadata:
+  annotations:
+    config.kubernetes.io/path: configmap_net-new.yaml
   name: net-new
 `)
 }

plugin/someteam.example.com/v1/starlarkmixer/mixer.star

@@ -1,11 +1,27 @@
 def run(r, fc):
+  add = []
+  remove = []
   for resource in r:
     if resource.get("metadata") == None:
       resource["metadata"] = {}
     if resource["metadata"].get("annotations") == None:
       resource["metadata"]["annotations"] = {}
+
+    # Flag for deletion
+    if resource["metadata"]["name"] == "delete-me":
+      remove.append(resource)
+      continue
+
+    # Deep-ish copy the resource
+    cp = dict(resource)
+    cp["metadata"] = dict(cp["metadata"])
+    cp["metadata"]["annotations"] = dict(cp["metadata"]["annotations"])
+    cp["metadata"]["name"] = resource["metadata"]["name"]+"-copy"
+    add.append(cp)
+
     resource["metadata"]["annotations"]["modified-by"] = fc["metadata"]["name"]
 
+  # Add something
   new = {
     "kind": "ConfigMap",
     "apiVersion": "v1",
@@ -13,6 +29,9 @@ def run(r, fc):
       "name": "net-new"
     }
   }
+  r.extend(add)
   r.append(new)
+  for resource in remove:
+    r.remove(resource)
 
 run(ctx.resource_list["items"], ctx.resource_list["functionConfig"])