Add support to accept function spec from catalogs

This commit modifies the logic to read function specs
from catalog in addition to the annotations. This feature
is currently enabled only with transformers.

Signed-off-by: Varsha Prasad Narsing <varshaprasad96@gmail.com>

api/filters/namespace/namespace.go

@@ -119,10 +119,10 @@ func (ns Filter) metaNamespaceHack(obj *yaml.RNode, gvk resid.Gvk) error {
 //
 // kind: RoleBinding
 // subjects:
-// - name: "default" # this will have the namespace set
-//   ...
-// - name: "something-else" # this will not have the namespace set
-//   ...
+//   - name: "default" # this will have the namespace set
+//     ...
+//   - name: "something-else" # this will not have the namespace set
+//     ...
 func (ns Filter) roleBindingHack(obj *yaml.RNode) error {
 	var visitor filtersutil.SetFn
 	switch ns.SetRoleBindingSubjects {

api/filters/valueadd/valueadd.go

@@ -19,25 +19,25 @@ import (
 //
 // - Non-existent target field.
 //
-//   The field will be added and the value inserted.
+//	The field will be added and the value inserted.
 //
 // - Existing field, scalar or map.
 //
-//   E.g. 'spec/template/spec/containers/[name:nginx]/image'
+//		E.g. 'spec/template/spec/containers/[name:nginx]/image'
 //
-//   This behaves like an IETF RFC 6902 Replace operation would;
-//   the existing value is replaced without complaint, even though
-//   this  is an Add operation.  In contrast, a Replace operation
-//   must fail (report an error) if the field doesn't exist.
+//		This behaves like an IETF RFC 6902 Replace operation would;
+//		the existing value is replaced without complaint, even though
+//		this  is an Add operation.  In contrast, a Replace operation
+//		must fail (report an error) if the field doesn't exist.
 //
-// - Existing field, list (array)
-//   Not supported yet.
-//   TODO: Honor fields with RFC-6902-style array indices
-//   TODO: like 'spec/template/spec/containers/2'
-//   TODO: Modify kyaml/yaml/PathGetter to allow this.
-//   The value will be inserted into the array at the given position,
-//   shifting other contents. To instead replace an array entry, use
-//   an implementation of an IETF RFC 6902 Replace operation.
+//	  - Existing field, list (array)
+//	    Not supported yet.
+//	    TODO: Honor fields with RFC-6902-style array indices
+//	    TODO: like 'spec/template/spec/containers/2'
+//	    TODO: Modify kyaml/yaml/PathGetter to allow this.
+//	    The value will be inserted into the array at the given position,
+//	    shifting other contents. To instead replace an array entry, use
+//	    an implementation of an IETF RFC 6902 Replace operation.
 //
 // For the common case of a filepath in the field value, and a desire
 // to add the value to the filepath (rather than replace the filepath),

api/internal/accumulator/namereferencetransformer.go

@@ -47,7 +47,6 @@ func newNameReferenceTransformer(
 //
 // If the Deployment's name changes, e.g. a prefix is added,
 // then the HPA's reference to the Deployment must be fixed.
-//
 func (t *nameReferenceTransformer) Transform(m resmap.ResMap) error {
 	fMap := t.determineFilters(m.Resources())
 	debug(fMap)
@@ -101,8 +100,8 @@ func debug(fMap filterMap) {
 //
 //   - kind: Deployment
 //     fieldSpecs:
-//     - kind: HorizontalPodAutoscaler
-//       path: spec/scaleTargetRef/name
+//   - kind: HorizontalPodAutoscaler
+//     path: spec/scaleTargetRef/name
 //
 // This entry says that an HPA, via its
 // 'spec/scaleTargetRef/name' field, may refer to a
@@ -152,7 +151,9 @@ func (t *nameReferenceTransformer) determineFilters(
 // how to parse fieldspec-style paths that make no distinction
 // between maps and sequences.  This means it cannot lookup commonly
 // used "indeterminate" paths like
-//    spec/containers/env/valueFrom/configMapKeyRef/name
+//
+//	spec/containers/env/valueFrom/configMapKeyRef/name
+//
 // ('containers' is a list, not a map).
 // However, the fieldspec filter does know how to handle this;
 // extract that code and call it here?

api/internal/plugins/builtinconfig/namebackreferences.go

@@ -24,24 +24,25 @@ import (
 //
 // If the name of a ConfigMap instance changed from 'alice' to 'bob',
 // one must
-//  - visit all objects that could refer to the ConfigMap (the Referrers)
-//  - see if they mention 'alice',
-//  - if so, change the Referrer's name reference to 'bob'.
+//   - visit all objects that could refer to the ConfigMap (the Referrers)
+//   - see if they mention 'alice',
+//   - if so, change the Referrer's name reference to 'bob'.
 //
 // The NameBackReferences instance to aid in this could look like
-//   {
-//     kind: ConfigMap
-//     version: v1
-//     fieldSpecs:
-//     - kind: Pod
-//       version: v1
-//       path: spec/volumes/configMap/name
-//     - kind: Deployment
-//       path: spec/template/spec/volumes/configMap/name
-//     - kind: Job
-//       path: spec/template/spec/volumes/configMap/name
-//       (etc.)
-//   }
+//
+//	{
+//	  kind: ConfigMap
+//	  version: v1
+//	  fieldSpecs:
+//	  - kind: Pod
+//	    version: v1
+//	    path: spec/volumes/configMap/name
+//	  - kind: Deployment
+//	    path: spec/template/spec/volumes/configMap/name
+//	  - kind: Job
+//	    path: spec/template/spec/volumes/configMap/name
+//	    (etc.)
+//	}
 type NameBackReferences struct {
 	resid.Gvk `json:",inline,omitempty" yaml:",inline,omitempty"`
 	// TODO: rename json 'fieldSpecs' to 'referrers' for clarity.

api/internal/plugins/doc.go

@@ -2,11 +2,9 @@
 // SPDX-License-Identifier: Apache-2.0
 
 /*
-
 Read docs/plugins.md first for an overview of kustomize plugins.
 
-
-BUILTIN PLUGIN CONFIGURATION
+# BUILTIN PLUGIN CONFIGURATION
 
 There are two kinds of plugins, Go plugins (shared
 object library) and exec plugins (independent binary).
@@ -18,22 +16,22 @@ follows.
 
 The plugin config file looks like
 
-  apiVersion: builtin
-  kind: SecretGenerator
-  metadata:
-    name: whatever
-  otherField1: whatever
-  otherField2: whatever
-  ...
+	apiVersion: builtin
+	kind: SecretGenerator
+	metadata:
+	  name: whatever
+	otherField1: whatever
+	otherField2: whatever
+	...
 
 The apiVersion must be 'builtin'.
 
 The kind is the CamelCase name of the plugin.
 
 The source for a builtin plugin must be at:
 
-  repo=$GOPATH/src/sigs.k8s.io/kustomize
-  ${repo}/plugin/builtin/LOWERCASE(${kind})/${kind}
+	repo=$GOPATH/src/sigs.k8s.io/kustomize
+	${repo}/plugin/builtin/LOWERCASE(${kind})/${kind}
 
 k8s wants 'kind' values to follow CamelCase, while
 Go style doesn't like but does allow such names.
@@ -42,8 +40,7 @@ The lowercased value of kind is used as the name of the
 directory holding the plugin, its test, and any
 optional associated files (possibly a go.mod file).
 
-
-BUILTIN PLUGIN GENERATION
+# BUILTIN PLUGIN GENERATION
 
 The `pluginator` program is a code generator that
 converts kustomize generator (G) and/or
@@ -52,32 +49,32 @@ code.
 
 It arises from following requirements:
 
-* extension
-  kustomize does two things - generate or
-  transform k8s resources.  Plugins let
-  users write their own G&T's without
-  having to fork kustomize and learn its
-  internals.
+  - extension
+    kustomize does two things - generate or
+    transform k8s resources.  Plugins let
+    users write their own G&T's without
+    having to fork kustomize and learn its
+    internals.
 
-* dogfooding
-  A G&T extension framework one can trust
-  should be used by its authors to deliver
-  builtin G&T's.
+  - dogfooding
+    A G&T extension framework one can trust
+    should be used by its authors to deliver
+    builtin G&T's.
 
-* distribution
-  kustomize should be distributable via
-  `go get` and should run where Go
-     programs are expected to run.
+  - distribution
+    kustomize should be distributable via
+    `go get` and should run where Go
+    programs are expected to run.
 
 The extension requirement led to building
 a framework that accommodates writing a
 G or T as either
 
-* an 'exec' plugin (any executable file
-  runnable as a kustomize subprocess), or
+  - an 'exec' plugin (any executable file
+    runnable as a kustomize subprocess), or
 
-* as a Go plugin - see
-  https://golang.org/pkg/plugin.
+  - as a Go plugin - see
+    https://golang.org/pkg/plugin.
 
 The dogfooding (and an implicit performance
 requirement) requires a 'builtin' G or T to
@@ -87,29 +84,27 @@ The distribution ('go get') requirement demands
 conversion of Go plugins to statically linked
 code, hence this program.
 
-
 TO GENERATE CODE
 
-  repo=$GOPATH/src/sigs.k8s.io/kustomize
-  cd $repo/plugin/builtin
-  go generate ./...
+	repo=$GOPATH/src/sigs.k8s.io/kustomize
+	cd $repo/plugin/builtin
+	go generate ./...
 
 This creates
 
-  $repo/api/plugins/builtins/SecretGenerator.go
+	$repo/api/plugins/builtins/SecretGenerator.go
 
 etc.
 
 Generated plugins are used in kustomize via
 
-  package whatever
-  import sigs.k8s.io/kustomize/api/plugins/builtins
-  ...
-  g := builtin.NewSecretGenerator()
-  g.Config(h, k)
-  resources, err := g.Generate()
-  err = g.Transform(resources)
-  // Eventually emit resources.
-
+	package whatever
+	import sigs.k8s.io/kustomize/api/plugins/builtins
+	...
+	g := builtin.NewSecretGenerator()
+	g.Config(h, k)
+	resources, err := g.Generate()
+	err = g.Transform(resources)
+	// Eventually emit resources.
 */
 package plugins

api/internal/plugins/fnplugin/fnplugin.go

@@ -6,10 +6,8 @@ package fnplugin
 import (
 	"bytes"
 	"fmt"
-	"os"
 
 	"sigs.k8s.io/kustomize/kyaml/errors"
-	k8syaml "sigs.k8s.io/yaml"
 
 	"sigs.k8s.io/kustomize/api/internal/plugins/utils"
 	"sigs.k8s.io/kustomize/api/resmap"
@@ -54,47 +52,31 @@ func resourceToRNode(res *resource.Resource) (*yaml.RNode, error) {
 }
 
 // GetFunctionSpec return function spec is there is. Otherwise return nil
-func GetFunctionSpec(res *resource.Resource) (*runtimeutil.FunctionSpec, error) {
-	rnode, err := resourceToRNode(res)
-	if err != nil {
-		return nil, fmt.Errorf("could not convert resource to RNode: %w", err)
-	}
-	functionSpec, err := runtimeutil.GetFunctionSpec(rnode)
-	if err != nil {
-		return nil, fmt.Errorf("failed to get FunctionSpec: %w", err)
-	}
-	return functionSpec, nil
-}
-
-func GetFunctionSpecFromCatalog(res *resource.Resource) (*runtimeutil.FunctionSpec, error) {
-	if res.GetKind() != framework.CatalogKind || res.GetApiVersion() != framework.FunctionDefinitionGroupVersion {
-		return nil, fmt.Errorf("invalid resource kind: %q and apiversion: %q", res.GetKind(), res.GetApiVersion())
-	}
+func GetFunctionSpec(res *resource.Resource, catalogs []framework.Catalog) (*runtimeutil.FunctionSpec, error) {
+	var (
+		functionSpec *runtimeutil.FunctionSpec
+		err          error
+	)
 
 	rnode, err := resourceToRNode(res)
 	if err != nil {
 		return nil, fmt.Errorf("could not convert resource to RNode: %w", err)
 	}
 
-	n, err := rnode.Pipe(yaml.Lookup("metadata", "configFn"))
-	if err != nil {
-		return nil, fmt.Errorf("failed to look up metadata.configFn: %w", err)
-	}
-	if yaml.IsMissingOrNull(n) {
-		return nil, nil
+	if len(catalogs) > 0 {
+		functionSpec, err = framework.FindMatchingFunctionSpec(rnode, catalogs)
+		if err != nil {
+			return nil, fmt.Errorf("failed to get FunctionSpec from catalogs: %w", err)
+		}
 	}
-	var fs runtimeutil.FunctionSpec
 
-	s, err := n.String()
-	if err != nil {
-		fmt.Fprintf(os.Stderr, "configFn parse error: %v\n", err)
-		return nil, fmt.Errorf("configFn parse error: %w", err)
-	}
-	if err := k8syaml.UnmarshalStrict([]byte(s), &fs); err != nil {
-		return nil, fmt.Errorf("%s unmarshal error: %w", "configFn", err)
+	if functionSpec == nil {
+		functionSpec, err = runtimeutil.GetFunctionSpec(rnode)
+		if err != nil {
+			return nil, fmt.Errorf("failed to get FunctionSpec: %w", err)
+		}
 	}
-	return &fs, nil
-
+	return functionSpec, nil
 }
 
 func toStorageMounts(mounts []string) []runtimeutil.StorageMount {
@@ -117,6 +99,7 @@ func NewFnPlugin(o *types.FnPluginLoadingOptions) *FnPlugin {
 			Env:            o.Env,
 			AsCurrentUser:  o.AsCurrentUser,
 			WorkingDir:     o.WorkingDir,
+			Catalogs:       o.Catalogs,
 		},
 	}
 }