feat: add support for server-side apply

See argoproj/argo-cd#2267

Signed-off-by: Mathieu Parent <[email protected]>

pkg/sync/common/types.go

@@ -27,6 +27,8 @@ const (
 	SyncOptionPruneLast = "PruneLast=true"
 	// Sync option that enables use of replace or create command instead of apply
 	SyncOptionReplace = "Replace=true"
+	// Sync option that enables use of --server-side flag instead of client-side
+	SyncOptionServerSideApply = "ServerSideApply=true"
 )
 
 type PermissionValidator func(un *unstructured.Unstructured, res *metav1.APIResource) error

pkg/sync/sync_context.go

@@ -179,6 +179,12 @@ func WithReplace(replace bool) SyncOpt {
 	}
 }
 
+func WithServerSideApply(serverSideApply bool) SyncOpt {
+	return func(ctx *syncContext) {
+		ctx.serverSideApply = serverSideApply
+	}
+}
+
 // NewSyncContext creates new instance of a SyncContext
 func NewSyncContext(
 	revision string,
@@ -320,6 +326,7 @@ type syncContext struct {
 	resourcesFilter        func(key kube.ResourceKey, target *unstructured.Unstructured, live *unstructured.Unstructured) bool
 	prune                  bool
 	replace                bool
+	serverSideApply        bool
 	pruneLast              bool
 	prunePropagationPolicy *metav1.DeletionPropagation
 
@@ -847,7 +854,7 @@ func (sc *syncContext) ensureCRDReady(name string) {
 	})
 }
 
-func (sc *syncContext) applyObject(t *syncTask, dryRun bool, force bool, validate bool) (common.ResultCode, string) {
+func (sc *syncContext) applyObject(t *syncTask, dryRun, force, validate bool) (common.ResultCode, string) {
 	dryRunStrategy := cmdutil.DryRunNone
 	if dryRun {
 		dryRunStrategy = cmdutil.DryRunClient
@@ -856,6 +863,7 @@ func (sc *syncContext) applyObject(t *syncTask, dryRun bool, force bool, validat
 	var err error
 	var message string
 	shouldReplace := sc.replace || resourceutil.HasAnnotationOption(t.targetObj, common.AnnotationSyncOptions, common.SyncOptionReplace)
+	serverSideApply := sc.serverSideApply || resourceutil.HasAnnotationOption(t.targetObj, common.AnnotationSyncOptions, common.SyncOptionServerSideApply)
 	if shouldReplace {
 		if t.liveObj != nil {
 			// Avoid using `kubectl replace` for CRDs since 'replace' might recreate resource and so delete all CRD instances
@@ -875,7 +883,7 @@ func (sc *syncContext) applyObject(t *syncTask, dryRun bool, force bool, validat
 			message, err = sc.resourceOps.CreateResource(context.TODO(), t.targetObj, dryRunStrategy, validate)
 		}
 	} else {
-		message, err = sc.resourceOps.ApplyResource(context.TODO(), t.targetObj, dryRunStrategy, force, validate)
+		message, err = sc.resourceOps.ApplyResource(context.TODO(), t.targetObj, dryRunStrategy, force, validate, serverSideApply)
 	}
 	if err != nil {
 		return common.ResultCodeSyncFailed, err.Error()

pkg/sync/sync_context_test.go

@@ -565,6 +565,52 @@ func TestSync_Replace(t *testing.T) {
 	}
 }
 
+func withServerSideApplyAnnotation(un *unstructured.Unstructured) *unstructured.Unstructured {
+	un.SetAnnotations(map[string]string{synccommon.AnnotationSyncOptions: synccommon.SyncOptionServerSideApply})
+	return un
+}
+
+func withReplaceAndServerSideApplyAnnotations(un *unstructured.Unstructured) *unstructured.Unstructured {
+	un.SetAnnotations(map[string]string{synccommon.AnnotationSyncOptions: "Replace=true,ServerSideApply=true"})
+	return un
+}
+
+func TestSync_ServerSideApply(t *testing.T) {
+	testCases := []struct {
+		name            string
+		target          *unstructured.Unstructured
+		live            *unstructured.Unstructured
+		commandUsed     string
+		serverSideApply bool
+	}{
+		{"NoAnnotation", NewPod(), NewPod(), "apply", false},
+		{"ServerSideApplyAnnotationIsSet", withServerSideApplyAnnotation(NewPod()), NewPod(), "apply", true},
+		{"ServerSideApplyAndReplaceAnnotationsAreSet", withReplaceAndServerSideApplyAnnotations(NewPod()), NewPod(), "replace", false},
+		{"LiveObjectMissing", withReplaceAnnotation(NewPod()), nil, "create", false},
+	}
+
+	for _, tc := range testCases {
+		t.Run(tc.name, func(t *testing.T) {
+			syncCtx := newTestSyncCtx()
+
+			tc.target.SetNamespace(FakeArgoCDNamespace)
+			if tc.live != nil {
+				tc.live.SetNamespace(FakeArgoCDNamespace)
+			}
+			syncCtx.resources = groupResources(ReconciliationResult{
+				Live:   []*unstructured.Unstructured{tc.live},
+				Target: []*unstructured.Unstructured{tc.target},
+			})
+
+			syncCtx.Sync()
+
+			kubectl, _ := syncCtx.kubectl.(*kubetest.MockKubectlCmd)
+			assert.Equal(t, tc.commandUsed, kubectl.GetLastResourceCommand(kube.GetResourceKey(tc.target)))
+			assert.Equal(t, tc.serverSideApply, kubectl.GetLastServerSideApply())
+		})
+	}
+}
+
 func TestSelectiveSyncOnly(t *testing.T) {
 	pod1 := NewPod()
 	pod1.SetName("pod-1")

pkg/utils/kube/kubetest/mock.go

@@ -31,6 +31,7 @@ type MockKubectlCmd struct {
 
 	lastCommandPerResource map[kube.ResourceKey]string
 	lastValidate           bool
+	serverSideApply        bool
 	recordLock             sync.RWMutex
 }
 
@@ -65,6 +66,19 @@ func (k *MockKubectlCmd) GetLastValidate() bool {
 	return validate
 }
 
+func (k *MockKubectlCmd) SetLastServerSideApply(serverSideApply bool) {
+	k.recordLock.Lock()
+	k.serverSideApply = serverSideApply
+	k.recordLock.Unlock()
+}
+
+func (k *MockKubectlCmd) GetLastServerSideApply() bool {
+	k.recordLock.RLock()
+	serverSideApply := k.serverSideApply
+	k.recordLock.RUnlock()
+	return serverSideApply
+}
+
 func (k *MockKubectlCmd) NewDynamicClient(config *rest.Config) (dynamic.Interface, error) {
 	return k.DynamicClient, nil
 }
@@ -107,8 +121,9 @@ func (k *MockKubectlCmd) UpdateResource(ctx context.Context, obj *unstructured.U
 	return obj, command.Err
 }
 
-func (k *MockKubectlCmd) ApplyResource(ctx context.Context, obj *unstructured.Unstructured, dryRunStrategy cmdutil.DryRunStrategy, force, validate bool) (string, error) {
+func (k *MockKubectlCmd) ApplyResource(ctx context.Context, obj *unstructured.Unstructured, dryRunStrategy cmdutil.DryRunStrategy, force, validate, serverSideApply bool) (string, error) {
 	k.SetLastValidate(validate)
+	k.SetLastServerSideApply(serverSideApply)
 	k.SetLastResourceCommand(kube.GetResourceKey(obj), "apply")
 	command, ok := k.Commands[obj.GetName()]
 	if !ok {

pkg/utils/kube/resource_ops.go

@@ -36,7 +36,7 @@ import (
 
 // ResourceOperations provides methods to manage k8s resources
 type ResourceOperations interface {
-	ApplyResource(ctx context.Context, obj *unstructured.Unstructured, dryRunStrategy cmdutil.DryRunStrategy, force, validate bool) (string, error)
+	ApplyResource(ctx context.Context, obj *unstructured.Unstructured, dryRunStrategy cmdutil.DryRunStrategy, force, validate, serverSideApply bool) (string, error)
 	ReplaceResource(ctx context.Context, obj *unstructured.Unstructured, dryRunStrategy cmdutil.DryRunStrategy, force bool) (string, error)
 	CreateResource(ctx context.Context, obj *unstructured.Unstructured, dryRunStrategy cmdutil.DryRunStrategy, validate bool) (string, error)
 	UpdateResource(ctx context.Context, obj *unstructured.Unstructured, dryRunStrategy cmdutil.DryRunStrategy) (*unstructured.Unstructured, error)
@@ -220,7 +220,7 @@ func (k *kubectlResourceOperations) UpdateResource(ctx context.Context, obj *uns
 }
 
 // ApplyResource performs an apply of a unstructured resource
-func (k *kubectlResourceOperations) ApplyResource(ctx context.Context, obj *unstructured.Unstructured, dryRunStrategy cmdutil.DryRunStrategy, force, validate bool) (string, error) {
+func (k *kubectlResourceOperations) ApplyResource(ctx context.Context, obj *unstructured.Unstructured, dryRunStrategy cmdutil.DryRunStrategy, force, validate, serverSideApply bool) (string, error) {
 	span := k.tracer.StartSpan("ApplyResource")
 	span.SetBaggageItem("kind", obj.GetKind())
 	span.SetBaggageItem("name", obj.GetName())
@@ -233,15 +233,15 @@ func (k *kubectlResourceOperations) ApplyResource(ctx context.Context, obj *unst
 		}
 		defer cleanup()
 
-		applyOpts, err := k.newApplyOptions(ioStreams, obj, fileName, validate, force, dryRunStrategy)
+		applyOpts, err := k.newApplyOptions(ioStreams, obj, fileName, validate, force, serverSideApply, dryRunStrategy)
 		if err != nil {
 			return err
 		}
 		return applyOpts.Run()
 	})
 }
 
-func (k *kubectlResourceOperations) newApplyOptions(ioStreams genericclioptions.IOStreams, obj *unstructured.Unstructured, fileName string, validate bool, force bool, dryRunStrategy cmdutil.DryRunStrategy) (*apply.ApplyOptions, error) {
+func (k *kubectlResourceOperations) newApplyOptions(ioStreams genericclioptions.IOStreams, obj *unstructured.Unstructured, fileName string, validate bool, force, serverSideApply bool, dryRunStrategy cmdutil.DryRunStrategy) (*apply.ApplyOptions, error) {
 	o := apply.NewApplyOptions(ioStreams)
 	dynamicClient, err := dynamic.NewForConfig(k.config)
 	if err != nil {
@@ -287,6 +287,7 @@ func (k *kubectlResourceOperations) newApplyOptions(ioStreams genericclioptions.
 	o.DeleteOptions.FilenameOptions.Filenames = []string{fileName}
 	o.Namespace = obj.GetNamespace()
 	o.DeleteOptions.ForceDeletion = force
+	o.ServerSideApply = serverSideApply
 	o.DryRunStrategy = dryRunStrategy
 	return o, nil
 }