Add minimal example

example/minimal/composition.yaml

@@ -0,0 +1,20 @@
+apiVersion: apiextensions.crossplane.io/v1
+kind: Composition
+metadata:
+  name: function-pkl
+spec:
+  compositeTypeRef:
+    apiVersion: example.crossplane.io/v1
+    kind: XR
+  mode: Pipeline
+  pipeline:
+    - step: run-the-template
+      functionRef:
+        name: function-pkl
+      input:
+        apiVersion: template.fn.crossplane.io/v1beta1
+        kind: Pkl
+        spec:
+          type: uri
+          # This pkl file is at `pkl/crossplane-example/minimal.pkl` in this repo
+          uri: "package://pkg.pkl-lang.org/github.com/crossplane-contrib/function-pkl/[email protected]#/minimal.pkl"

example/minimal/functions.yaml

@@ -0,0 +1,11 @@
+---
+apiVersion: pkg.crossplane.io/v1beta1
+kind: Function
+metadata:
+  name: function-pkl
+  annotations:
+    # This tells crossplane beta render to connect to the function locally.
+    render.crossplane.io/runtime: Development
+spec:
+  # This is ignored when using the Development runtime.
+  package: function-pkl

example/minimal/xr.yaml

@@ -0,0 +1,6 @@
+# Replace this with your XR!
+apiVersion: example.crossplane.io/v1
+kind: XR
+metadata:
+  name: example-xr
+spec: {}

go.sum

@@ -261,8 +261,6 @@ google.golang.org/genproto/googleapis/rpc v0.0.0-20240509183442-62759503f434 h1:
 google.golang.org/genproto/googleapis/rpc v0.0.0-20240509183442-62759503f434/go.mod h1:I7Y+G38R2bu5j1aLzfFmQfTcU/WnFuqDwLZAbvKTKpM=
 google.golang.org/grpc v1.63.2 h1:MUeiw1B2maTVZthpU5xvASfTh3LDbxHd6IJ6QQVU+xM=
 google.golang.org/grpc v1.63.2/go.mod h1:WAX/8DgncnokcFUldAxq7GeB5DXHDbMF+lLvDomNkRA=
-google.golang.org/protobuf v1.34.1 h1:9ddQBjfCyZPOHPUiPxpYESBLc+T8P3E+Vo4IbKZgFWg=
-google.golang.org/protobuf v1.34.1/go.mod h1:c6P6GXX6sHbq/GpV6MGZEdwhWPcYBgnhAHhKbcUYpos=
 google.golang.org/protobuf v1.34.2 h1:6xV6lTsCfpGD21XK49h7MhtcApnLqkfYgPcdHftf6hg=
 google.golang.org/protobuf v1.34.2/go.mod h1:qYOHts0dSfpeUzUFpOMr/WGzszTmLH+DiWniOlNbLDw=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
@@ -282,8 +280,6 @@ k8s.io/api v0.30.0 h1:siWhRq7cNjy2iHssOB9SCGNCl2spiF1dO3dABqZ8niA=
 k8s.io/api v0.30.0/go.mod h1:OPlaYhoHs8EQ1ql0R/TsUgaRPhpKNxIMrKQfWUp8QSE=
 k8s.io/apiextensions-apiserver v0.30.0 h1:jcZFKMqnICJfRxTgnC4E+Hpcq8UEhT8B2lhBcQ+6uAs=
 k8s.io/apiextensions-apiserver v0.30.0/go.mod h1:N9ogQFGcrbWqAY9p2mUAL5mGxsLqwgtUce127VtRX5Y=
-k8s.io/apimachinery v0.30.0 h1:qxVPsyDM5XS96NIh9Oj6LavoVFYff/Pon9cZeDIkHHA=
-k8s.io/apimachinery v0.30.0/go.mod h1:iexa2somDaxdnj7bha06bhb43Zpa6eWH8N8dbqVjTUc=
 k8s.io/apimachinery v0.30.2 h1:fEMcnBj6qkzzPGSVsAZtQThU62SmQ4ZymlXRC5yFSCg=
 k8s.io/apimachinery v0.30.2/go.mod h1:iexa2somDaxdnj7bha06bhb43Zpa6eWH8N8dbqVjTUc=
 k8s.io/client-go v0.30.0 h1:sB1AGGlhY/o7KCyCEQ0bPWzYDL0pwOZO4vAtTSh/gJQ=

internal/function/fn.go

@@ -87,7 +87,6 @@ func (f *Function) RunFunction(ctx context.Context, req *fnv1beta1.RunFunctionRe
 				Ctx: ctx,
 			}))
 	}
-
 	if err != nil {
 		response.Fatal(rsp, errors.Wrap(err, "could not create Pkl Evaluator"))
 		return rsp, nil
@@ -104,34 +103,43 @@ func (f *Function) RunFunction(ctx context.Context, req *fnv1beta1.RunFunctionRe
 		return rsp, nil
 	}
 
-	helperResponse := &helper.CompositionResponse{}
-	err = yaml.Unmarshal([]byte(renderedManifest), helperResponse)
+	rsp, err = toResponse(renderedManifest, req.GetMeta().GetTag())
 	if err != nil {
-		return nil, errors.Wrapf(err, "rendered Pkl file was not in expected format. did you amend @crossplane/CompositionResponse.pkl?")
+		response.Fatal(rsp, errors.Wrap(err, "error while converting Pkl file"))
+		return rsp, nil
 	}
 
-	fixedRequirements := &fnv1beta1.Requirements{
-		ExtraResources: convertExtraResources(helperResponse.Requirements.ExtraResources),
+	return rsp, nil
+}
+
+func toResponse(renderedManifest, tag string) (*fnv1beta1.RunFunctionResponse, error) {
+	rspHelper := &helper.CompositionResponse{}
+	err := yaml.Unmarshal([]byte(renderedManifest), rspHelper)
+	if err != nil {
+		return nil, errors.Wrapf(err, "rendered Pkl file was not in expected format. did you amend @crossplane/CompositionResponse.pkl?")
 	}
 
 	responseMeta := &fnv1beta1.ResponseMeta{
-		Tag: req.GetMeta().GetTag(),
+		Tag: tag,
 		Ttl: durationpb.New(response.DefaultTTL),
 	}
+	if ttl := rspHelper.GetMeta().GetTtl(); ttl != nil {
+		responseMeta.Ttl = ttl
+	}
 
 	// Note: consider not overwriting rsp and whether it makes a difference.
-	rsp = &fnv1beta1.RunFunctionResponse{
-		Meta:         responseMeta,
-		Desired:      helperResponse.Desired,
-		Results:      helperResponse.Results,
-		Context:      helperResponse.Context,
-		Requirements: fixedRequirements,
+	rsp := &fnv1beta1.RunFunctionResponse{
+		Meta:    responseMeta,
+		Desired: rspHelper.Desired,
+		Results: rspHelper.Results,
+		Context: rspHelper.Context,
 	}
 
-	if ttl := helperResponse.GetMeta().GetTtl(); ttl != nil {
-		rsp.Meta.Ttl = ttl
+	if rspHelper.Requirements != nil && rspHelper.Requirements.ExtraResources != nil {
+		rsp.Requirements = &fnv1beta1.Requirements{
+			ExtraResources: convertExtraResources(rspHelper.Requirements.ExtraResources),
+		}
 	}
-
 	return rsp, nil
 }
 

internal/function/fn_test.go

@@ -29,6 +29,7 @@ import (
 	"github.com/crossplane/crossplane-runtime/pkg/logging"
 	fnv1beta1 "github.com/crossplane/function-sdk-go/proto/v1beta1"
 	"github.com/crossplane/function-sdk-go/resource"
+	"github.com/crossplane/function-sdk-go/response"
 
 	"github.com/crossplane-contrib/function-pkl/input/v1beta1"
 )
@@ -54,6 +55,71 @@ func TestRunFunction(t *testing.T) {
 		args   args
 		want   want
 	}{
+		"Minimal": {
+			reason: "The Function should create a single resource",
+			args: args{
+				ctx: context.TODO(),
+				req: &fnv1beta1.RunFunctionRequest{
+					Input: resource.MustStructObject(&v1beta1.Pkl{
+						Spec: v1beta1.PklSpec{
+							Type: "local",
+							Local: &v1beta1.Local{
+								ProjectDir: pklPackage,
+								File:       pklPackage + "/minimal.pkl",
+							},
+						},
+					}),
+					Observed: &fnv1beta1.State{
+						Composite: &fnv1beta1.Resource{
+							Resource: resource.MustStructJSON(`{
+								"apiVersion": "example.crossplane.io/v1",
+								"kind": "XR",
+								"metadata": {
+									"name": "example-xr"
+								},
+								"spec": {}
+							}`),
+						},
+					},
+				},
+			},
+			want: want{
+				rsp: &fnv1beta1.RunFunctionResponse{
+					Meta: &fnv1beta1.ResponseMeta{
+						Ttl: durationpb.New(response.DefaultTTL),
+					},
+					Desired: &fnv1beta1.State{
+						Composite: &fnv1beta1.Resource{},
+						Resources: map[string]*fnv1beta1.Resource{
+							"cm-minimal": {
+								Resource: resource.MustStructJSON(`{
+									"apiVersion": "kubernetes.crossplane.io/v1alpha2",
+									"kind": "Object",
+									"metadata": {
+										"name": "cm-one"
+									},
+									"spec": {
+										"forProvider": {
+											"manifest": {
+												"apiVersion": "v1",
+												"kind": "ConfigMap",
+												"metadata": {
+													"name": "cm-minimal",
+													"namespace": "crossplane-system"
+												},
+												"data": {
+													"foo": "bar"
+												}
+											}
+										}
+									}
+								}`),
+							},
+						},
+					},
+				},
+			},
+		},
 		"Full": {
 			reason: "The Function should create a full functionResult",
 			args: args{

pkl/crossplane.contrib.example/full.pkl

@@ -1,5 +1,4 @@
 amends "@crossplane.contrib/CompositionResponse.pkl"
-import "@crossplane.contrib/Resource.pkl"
 import "@crossplane.contrib/crossplane.pkl"
 
 import "crds/XR.pkl"
@@ -42,7 +41,7 @@ desired {
     }
   }
   resources {
-    ["cm-one"] = new Resource {
+    ["cm-one"] = new {
       resource = new Object {
         metadata {
           name = "cm-one"

pkl/crossplane.contrib.example/minimal.pkl

@@ -0,0 +1,28 @@
+amends "@crossplane.contrib/CompositionResponse.pkl"
+import "crds/Object.pkl"
+import "@k8s/api/core/v1/ConfigMap.pkl"
+
+desired {
+  resources {
+    ["cm-minimal"] = new {
+      resource = new Object {
+        metadata {
+          name = "cm-one"
+        }
+        spec {
+          forProvider {
+            manifest = new ConfigMap {
+              metadata {
+                name = "cm-minimal"
+                namespace = "crossplane-system"
+              }
+              data {
+                ["foo"] = "bar"
+              }
+            }
+          }
+        }
+      }
+    }
+  }
+}