Implemented logic for function

.golangci.yml

@@ -36,8 +36,6 @@ linters-settings:
     sections:
       - standard
       - default
-      - prefix(github.com/crossplane)
-      - prefix(github.com/crossplane-contrib)
       - blank
       - dot
 

example/composition.yaml

@@ -1,17 +1,67 @@
 apiVersion: apiextensions.crossplane.io/v1
 kind: Composition
 metadata:
-  name: function-template-go
+  name: function-switcher
 spec:
-  compositeTypeRef:
-    apiVersion: example.crossplane.io/v1
-    kind: XR
   mode: Pipeline
   pipeline:
-  - step: run-the-template
+  - step: patch-and-transform
     functionRef:
-      name: function-template-go
+      name: function-patch-and-transform
     input:
-      apiVersion: template.fn.crossplane.io/v1beta1
-      kind: Input
-      example: "Hello world"
+      apiVersion: pt.fn.crossplane.io/v1beta1
+      kind: Resources
+      resources:
+
+      - name: resourceOne
+        base:
+          apiVersion: example.crossplane.io/v1
+          kind: Resource
+          spec:
+            field1: ""
+            field2: ""
+        patches:
+          - type: FromCompositeFieldPath
+            fromFieldPath: "spec.resourceOne.field1"
+            toFieldPath: "spec.field1"
+          - type: FromCompositeFieldPath
+            fromFieldPath: "spec.resourceOne.field2"
+            toFieldPath: "spec.field2"
+
+      - name: resourceTwo
+        base:
+          apiVersion: example.crossplane.io/v1
+          kind: Resource
+          spec:
+            field1: ""
+            field2: ""
+        patches:
+          - type: FromCompositeFieldPath
+            fromFieldPath: "spec.resourceTwo.field1"
+            toFieldPath: "spec.field1"
+          - type: FromCompositeFieldPath
+            fromFieldPath: "spec.resourceTwo.field2"
+            toFieldPath: "spec.field2"
+
+      - name: resourceThree
+        base:
+          apiVersion: example.crossplane.io/v1
+          kind: Resource
+          spec:
+            field1: ""
+            field2: ""
+        patches:
+          - type: FromCompositeFieldPath
+            fromFieldPath: "spec.resourceThree.field1"
+            toFieldPath: "spec.field1"
+          - type: FromCompositeFieldPath
+            fromFieldPath: "spec.resourceThree.field2"
+            toFieldPath: "spec.field2"
+
+  - step: enable-disable
+    functionRef:
+      name: function-switcher
+
+  compositeTypeRef:
+    apiVersion: example.crossplane.io/v1
+    kind: XR

example/functions.yaml

@@ -2,10 +2,15 @@
 apiVersion: pkg.crossplane.io/v1beta1
 kind: Function
 metadata:
-  name: function-template-go
+  name: function-switcher
   annotations:
-    # This tells crossplane beta render to connect to the function locally.
     render.crossplane.io/runtime: Development
+# spec:
+  # package: ghcr.io/kndpio/kndp/function-switcher:0.1.0
+---
+apiVersion: pkg.crossplane.io/v1beta1
+kind: Function
+metadata:
+  name: function-patch-and-transform
 spec:
-  # This is ignored when using the Development runtime.
-  package: function-template-go
+  package: xpkg.upbound.io/crossplane-contrib/function-patch-and-transform:v0.1.4

example/xr.yaml

@@ -1,6 +1,16 @@
-# Replace this with your XR!
 apiVersion: example.crossplane.io/v1
 kind: XR
 metadata:
   name: example-xr
-spec: {}
+  annotations:
+    switcher.fn.kndp.io/disabled: "resourceTwo"
+spec:
+  resourceOne:
+    field1: "one"
+    field2: "two"
+  resourceTwo:
+    field1: "three"
+    field2: "four"
+  resourceThree:
+    field1: "five"
+    field2: "six"

fn.go

@@ -2,13 +2,17 @@ package main
 
 import (
 	"context"
+	"encoding/json"
+	"slices"
+	"strings"
 
-	"github.com/crossplane/crossplane-runtime/pkg/errors"
-	"github.com/crossplane/crossplane-runtime/pkg/logging"
+	"github.com/crossplane/function-sdk-go/logging"
 	fnv1beta1 "github.com/crossplane/function-sdk-go/proto/v1beta1"
 	"github.com/crossplane/function-sdk-go/request"
+	"github.com/crossplane/function-sdk-go/resource"
 	"github.com/crossplane/function-sdk-go/response"
-	"github.com/crossplane/function-template-go/input/v1beta1"
+	"github.com/pkg/errors"
+	v1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
 // Function returns whatever response you ask it to.
@@ -24,15 +28,88 @@ func (f *Function) RunFunction(_ context.Context, req *fnv1beta1.RunFunctionRequ
 
 	rsp := response.To(req, response.DefaultTTL)
 
-	in := &v1beta1.Input{}
-	if err := request.GetInput(req, in); err != nil {
-		response.Fatal(rsp, errors.Wrapf(err, "cannot get Function input from %T", req))
+	desired, err := request.GetDesiredComposedResources(req)
+	if err != nil {
+		response.Fatal(rsp, err)
 		return rsp, nil
 	}
 
-	// TODO: Add your Function logic here!
-	response.Normalf(rsp, "I was run with input %q!", in.Example)
-	f.log.Info("I was run!", "input", in.Example)
+	switchOn, switchOff, err := collectSwitches(req, rsp)
+	if err != nil {
+		return rsp, err
+	}
+
+	filterDesired(desired, switchOff, switchOn)
+
+	rsp.Desired.Resources = nil
+
+	if err := response.SetDesiredComposedResources(rsp, desired); err != nil {
+		response.Fatal(rsp, errors.Wrapf(err, "cannot set desired composed resources in %T", rsp))
+		return rsp, nil
+	}
 
 	return rsp, nil
 }
+
+func collectSwitches(req *fnv1beta1.RunFunctionRequest, rsp *fnv1beta1.RunFunctionResponse) ([]string, []string, error) {
+	oxr, err := request.GetObservedCompositeResource(req)
+	if err != nil {
+		response.Fatal(rsp, errors.Wrapf(err, "cannot get observed composite resource from %T", req))
+		return nil, nil, err
+	}
+	var switchOn []string
+	var switchOff []string
+	m := oxr.Resource.Object["metadata"]
+
+	meta, err := toMeta(m)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	for k, v := range meta.Annotations {
+		if strings.Contains(k, "switcher.fn.kndp.io/enabled") {
+			if switchOn == nil {
+				switchOn = []string{}
+			}
+			switchOn = append(switchOn, strings.Split(v, ",")...)
+		}
+
+		if strings.Contains(k, "switcher.fn.kndp.io/disabled") {
+			if switchOff == nil {
+				switchOff = []string{}
+			}
+			switchOff = append(switchOff, strings.Split(v, ",")...)
+		}
+	}
+
+	return switchOn, switchOff, nil
+}
+
+func filterDesired(desired map[resource.Name]*resource.DesiredComposed, switchOff []string, switchOn []string) map[resource.Name]*resource.DesiredComposed {
+
+	for r := range desired {
+		if switchOff != nil && slices.Contains[[]string, string](switchOff, string(r)) {
+			delete(desired, r)
+		}
+		if switchOn != nil && !slices.Contains[[]string, string](switchOn, string(r)) {
+			delete(desired, r)
+		}
+	}
+
+	return desired
+}
+
+func toMeta(m interface{}) (v1.ObjectMeta, error) {
+	meta := v1.ObjectMeta{}
+
+	mm, err := json.Marshal(m)
+	if err != nil {
+		return meta, err
+	}
+	err = json.Unmarshal(mm, &meta)
+	if err != nil {
+		return meta, err
+	}
+
+	return meta, nil
+}