Feat: add apply

Signed-off-by: Yin Da <[email protected]>

util/builder/option.go

@@ -0,0 +1,53 @@
+/*
+Copyright 2023 The KubeVela Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package builder
+
+// Option the generic type for option type T
+type Option[T any] interface {
+	ApplyTo(*T)
+}
+
+// Constructor the constructor for option interface
+type Constructor[T any] interface {
+	New() *T
+}
+
+// NewOptions create options T with given Option args. If T implements
+// Constructor, it will call its construct function to initialize first
+func NewOptions[T any](opts ...Option[T]) *T {
+	t := new(T)
+	if c, ok := any(t).(Constructor[T]); ok {
+		t = c.New()
+	}
+	ApplyTo(t, opts...)
+	return t
+}
+
+// ApplyTo run all option args for setting the options
+func ApplyTo[T any](t *T, opts ...Option[T]) {
+	for _, opt := range opts {
+		opt.ApplyTo(t)
+	}
+}
+
+// OptionFn wrapper for ApplyTo function
+type OptionFn[T any] func(*T)
+
+// ApplyTo implements Option interface
+func (in OptionFn[T]) ApplyTo(t *T) {
+	(in)(t)
+}

util/builder/option_test.go

@@ -0,0 +1,47 @@
+/*
+Copyright 2023 The KubeVela Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package builder_test
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/kubevela/pkg/util/builder"
+)
+
+type B struct {
+	key string
+	val string
+}
+
+func (in *B) New() *B {
+	return &B{key: "key"}
+}
+
+type Suffix string
+
+func (in Suffix) ApplyTo(b *B) {
+	b.key += string(in)
+}
+
+func TestOption(t *testing.T) {
+	opt := builder.OptionFn[B](func(b *B) { b.val = "val" })
+	b := builder.NewOptions[B](opt, Suffix("-x"))
+	require.Equal(t, "key-x", b.key)
+	require.Equal(t, "val", b.val)
+}

util/k8s/apply/apply.go

@@ -0,0 +1,150 @@
+/*
+Copyright 2023 The KubeVela Authors.
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+	http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package apply
+
+import (
+	"context"
+	"fmt"
+
+	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
+	"k8s.io/klog/v2"
+	"sigs.k8s.io/controller-runtime/pkg/client"
+	"sigs.k8s.io/controller-runtime/pkg/client/apiutil"
+
+	"github.com/kubevela/pkg/util/k8s/patch"
+)
+
+// Apply try to get desired object and update it, if not exist, create it
+// The procedure of Apply is
+// 1. Get the desired object
+// 2. Run the PreApplyHook
+// 3. If not exist, run the PreCreateHook and create the target object, exit
+// 4. If exists, run the PreUpdateHook, get the UpdateStrategy, decide how to update
+// 5. If Patch, get patch.PatchAction (implemented by PatchActionProvider)
+// 6. Do the update operation
+// The above procedure will also be affected by the DryRunOption
+func Apply(ctx context.Context, c client.Client, desired client.Object, opts Options) error {
+	// wrap client for apply spec & status
+	c = &Client{c}
+
+	// pre-fill types
+	if desired.GetObjectKind().GroupVersionKind().Kind == "" {
+		if gvk, err := apiutil.GVKForObject(desired, c.Scheme()); err == nil {
+			desired.GetObjectKind().SetGroupVersionKind(gvk)
+		}
+	}
+
+	// get existing
+	existing, err := get(ctx, c, desired)
+	if err != nil {
+		return fmt.Errorf("cannot get object: %w", err)
+	}
+
+	if hook, ok := opts.(PreApplyHook); ok {
+		if err = hook.PreApply(desired); err != nil {
+			return err
+		}
+	}
+
+	// create
+	if existing == nil {
+		if err = create(ctx, c, desired, opts); err != nil {
+			return fmt.Errorf("cannot create object: %w", err)
+		}
+		return nil
+	}
+
+	// update
+	if err = update(ctx, c, existing, desired, opts); err != nil {
+		return fmt.Errorf("cannot update object: %w", err)
+	}
+	return nil
+}
+
+func get(ctx context.Context, c client.Client, desired client.Object) (client.Object, error) {
+	o := &unstructured.Unstructured{}
+	o.SetGroupVersionKind(desired.GetObjectKind().GroupVersionKind())
+	if err := c.Get(ctx, client.ObjectKeyFromObject(desired), o); err != nil {
+		return nil, client.IgnoreNotFound(err)
+	}
+	return o, nil
+}
+
+func create(ctx context.Context, c client.Client, desired client.Object, act Options) error {
+	if hook, ok := act.(PreCreateHook); ok {
+		if err := hook.PreCreate(desired); err != nil {
+			return err
+		}
+	}
+	klog.V(4).InfoS("creating object", "resource", klog.KObj(desired))
+	return c.Create(ctx, desired, act.DryRun())
+}
+
+func update(ctx context.Context, c client.Client, existing client.Object, desired client.Object, act Options) error {
+	if hook, ok := act.(PreUpdateHook); ok {
+		if err := hook.PreUpdate(existing, desired); err != nil {
+			return err
+		}
+	}
+	strategy, err := act.GetUpdateStrategy(existing, desired)
+	if err != nil {
+		return err
+	}
+	switch strategy {
+	case Recreate:
+		klog.V(4).InfoS("recreating object", "resource", klog.KObj(desired))
+		if act.DryRun() { // recreate does not support dryrun
+			return nil
+		}
+		if existing.GetDeletionTimestamp() == nil {
+			if err := c.Delete(ctx, existing); err != nil {
+				return fmt.Errorf("failed to delete object: %w", err)
+			}
+		}
+		return c.Create(ctx, desired)
+	case Replace:
+		klog.V(4).InfoS("replacing object", "resource", klog.KObj(desired))
+		desired.SetResourceVersion(existing.GetResourceVersion())
+		return c.Update(ctx, desired, act.DryRun())
+	case Patch:
+		klog.V(4).InfoS("patching object", "resource", klog.KObj(desired))
+		patchAction := patch.PatchAction{}
+		if prd, ok := act.(PatchActionProvider); ok {
+			patchAction = prd.GetPatchAction()
+		}
+		pat, err := patch.ThreeWayMergePatch(existing, desired, &patchAction)
+		if err != nil {
+			return fmt.Errorf("cannot calculate patch by computing a three way diff: %w", err)
+		}
+		if isEmptyPatch(pat) {
+			return nil
+		}
+		return c.Patch(ctx, desired, pat, act.DryRun())
+	case Skip:
+		return nil
+	default:
+		return fmt.Errorf("unrecognizable update strategy: %v", strategy)
+	}
+}
+
+func isEmptyPatch(patch client.Patch) bool {
+	if patch == nil {
+		return true
+	}
+	data, _ := patch.Data(nil)
+	return data == nil || string(data) == "{}"
+}