Take into account the server-side inventory for local diff

If implemented users will be able to use a local kustomization file while
retrieving status from the live kustomization file.

Signed-off-by: Soule BA <soule@weave.works>

internal/build/build.go

@@ -204,19 +204,36 @@ func NewBuilder(name, resources string, opts ...BuilderOptionFunc) (*Builder, er
 	return b, nil
 }
 
+func (b *Builder) resolveKustomization(liveKus *kustomizev1.Kustomization) (k *kustomizev1.Kustomization, err error) {
+	// local kustomization file takes precedence over live kustomization
+	if b.kustomizationFile != "" {
+		k, err = b.unMarshallKustomization()
+		if err != nil {
+			return
+		}
+		if !b.dryRun && liveKus != nil && liveKus.Status.Inventory != nil {
+			// merge the live kustomization status with the local kustomization in order to get the
+			// live resources status
+			k.Status = *liveKus.Status.DeepCopy()
+		}
+	} else {
+		k = liveKus
+	}
+	return
+}
+
 func (b *Builder) getKustomization(ctx context.Context) (*kustomizev1.Kustomization, error) {
+	liveKus := &kustomizev1.Kustomization{}
 	namespacedName := types.NamespacedName{
 		Namespace: b.namespace,
 		Name:      b.name,
 	}
-
-	k := &kustomizev1.Kustomization{}
-	err := b.client.Get(ctx, namespacedName, k)
+	err := b.client.Get(ctx, namespacedName, liveKus)
 	if err != nil {
 		return nil, err
 	}
 
-	return k, nil
+	return liveKus, nil
 }
 
 // Build builds the yaml manifests from the kustomization object
@@ -251,19 +268,18 @@ func (b *Builder) build() (m resmap.ResMap, err error) {
 	defer cancel()
 
 	// Get the kustomization object
-	var k *kustomizev1.Kustomization
-	if b.kustomizationFile != "" {
-		k, err = b.unMarshallKustomization()
+	liveKus := &kustomizev1.Kustomization{}
+	if !b.dryRun {
+		liveKus, err = b.getKustomization(ctx)
 		if err != nil {
-			return
-		}
-	} else {
-		k, err = b.getKustomization(ctx)
-		if err != nil {
-			err = fmt.Errorf("failed to get kustomization object: %w", err)
-			return
+			return nil, fmt.Errorf("failed to get kustomization object: %w", err)
 		}
 	}
+	k, err := b.resolveKustomization(liveKus)
+	if err != nil {
+		err = fmt.Errorf("failed to get kustomization object: %w", err)
+		return
+	}
 
 	// store the kustomization object
 	b.kustomization = k

internal/build/build_test.go

@@ -17,10 +17,15 @@ limitations under the License.
 package build
 
 import (
+	"fmt"
 	"strings"
 	"testing"
+	"time"
 
+	kustomizev1 "github.com/fluxcd/kustomize-controller/api/v1"
+	"github.com/fluxcd/pkg/apis/meta"
 	"github.com/google/go-cmp/cmp"
+	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 	"sigs.k8s.io/kustomize/api/resource"
 	"sigs.k8s.io/kustomize/kyaml/yaml"
 )
@@ -215,3 +220,135 @@ func Test_unMarshallKustomization(t *testing.T) {
 		})
 	}
 }
+
+func Test_ResolveKustomization(t *testing.T) {
+	tests := []struct {
+		name              string
+		localKsFile       string
+		liveKustomization *kustomizev1.Kustomization
+		dryrun            bool
+	}{
+		{
+			name:        "valid kustomization",
+			localKsFile: "testdata/local-kustomization/valid.yaml",
+		},
+		{
+			name:        "local and live kustomization",
+			localKsFile: "testdata/local-kustomization/valid.yaml",
+			liveKustomization: &kustomizev1.Kustomization{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "podinfo",
+					Namespace: "flux-system",
+				},
+				Spec: kustomizev1.KustomizationSpec{
+					Interval: metav1.Duration{Duration: time.Minute * 5},
+					Path:     "./testdata/local-kustomization/valid.yaml",
+				},
+				Status: kustomizev1.KustomizationStatus{
+					Conditions: []metav1.Condition{
+						{
+							Type:   meta.ReadyCondition,
+							Status: metav1.ConditionTrue,
+						},
+					},
+					Inventory: &kustomizev1.ResourceInventory{
+						Entries: []kustomizev1.ResourceRef{
+							{
+								ID:      "flux-system_podinfo_v1_service_podinfo",
+								Version: "v1",
+							},
+						},
+					},
+				},
+			},
+		},
+		{
+			name:        "local and live kustomization with dryrun",
+			localKsFile: "testdata/local-kustomization/valid.yaml",
+			liveKustomization: &kustomizev1.Kustomization{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "podinfo",
+					Namespace: "flux-system",
+				},
+				Spec: kustomizev1.KustomizationSpec{
+					Interval: metav1.Duration{Duration: time.Minute * 5},
+					Path:     "./testdata/local-kustomization/valid.yaml",
+				},
+				Status: kustomizev1.KustomizationStatus{
+					Conditions: []metav1.Condition{
+						{
+							Type:   meta.ReadyCondition,
+							Status: metav1.ConditionTrue,
+						},
+					},
+					Inventory: &kustomizev1.ResourceInventory{
+						Entries: []kustomizev1.ResourceRef{
+							{
+								ID:      "flux-system_podinfo_v1_service_podinfo",
+								Version: "v1",
+							},
+						},
+					},
+				},
+			},
+			dryrun: true,
+		},
+		{
+			name: "live kustomization",
+			liveKustomization: &kustomizev1.Kustomization{
+				ObjectMeta: metav1.ObjectMeta{
+					Name:      "podinfo",
+					Namespace: "flux-system",
+				},
+				Spec: kustomizev1.KustomizationSpec{
+					Interval: metav1.Duration{Duration: time.Minute * 5},
+					Path:     "./testdata/local-kustomization/valid.yaml",
+				},
+				Status: kustomizev1.KustomizationStatus{
+					Conditions: []metav1.Condition{
+						{
+							Type:   meta.ReadyCondition,
+							Status: metav1.ConditionTrue,
+						},
+					},
+					Inventory: &kustomizev1.ResourceInventory{
+						Entries: []kustomizev1.ResourceRef{
+							{
+								ID:      "flux-system_podinfo_v1_service_podinfo",
+								Version: "v1",
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+
+	b := &Builder{}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			b.kustomizationFile = tt.localKsFile
+			b.dryRun = tt.dryrun
+			ks, err := b.resolveKustomization(tt.liveKustomization)
+			if err != nil {
+				t.Errorf("unexpected err '%s'", err)
+			}
+			if !tt.dryrun {
+				if b.kustomizationFile == "" {
+					if cmp.Diff(ks, tt.liveKustomization) != "" {
+						t.Errorf("expected kustomization to match live kustomization")
+					}
+				} else {
+					if tt.liveKustomization != nil && cmp.Diff(ks.Status, tt.liveKustomization.Status) != "" {
+						t.Errorf("expected kustomization status to match live kustomization status")
+					}
+				}
+			} else {
+				if ks.Status.Inventory != nil {
+					fmt.Println(ks.Status.Inventory)
+					t.Errorf("expected kustomization status to be nil")
+				}
+			}
+		})
+	}
+}

internal/build/diff.go

@@ -136,11 +136,14 @@ func (b *Builder) Diff() (string, bool, error) {
 	if b.kustomization.Spec.Prune && len(diffErrs) == 0 {
 		oldStatus := b.kustomization.Status.DeepCopy()
 		if oldStatus.Inventory != nil {
-			diffObjects, err := diffInventory(oldStatus.Inventory, newInventory)
+			staleObjects, err := diffInventory(oldStatus.Inventory, newInventory)
 			if err != nil {
 				return "", createdOrDrifted, err
 			}
-			for _, object := range diffObjects {
+			if len(staleObjects) > 0 {
+				createdOrDrifted = true
+			}
+			for _, object := range staleObjects {
 				output.WriteString(writeString(fmt.Sprintf("► %s deleted\n", ssa.FmtUnstructured(object)), bunt.OrangeRed))
 			}
 		}