[module-sdk] expose readonly Settings on ApplicationHookInput (#103)

Signed-off-by: Artem Kuleshov <artem.kuleshov@flant.com>

Author: Fkuloff

examples/single-file-app-example/hooks/go.mod

@@ -7,6 +7,7 @@ require (
 	github.com/deckhouse/module-sdk v0.0.0
 	github.com/onsi/ginkgo v1.16.5
 	github.com/onsi/gomega v1.36.1
+	github.com/tidwall/gjson v1.18.0
 	k8s.io/apimachinery v0.33.8
 )
 
@@ -60,7 +61,6 @@ require (
 	github.com/spf13/cobra v1.9.1 // indirect
 	github.com/spf13/pflag v1.0.6 // indirect
 	github.com/sylabs/oci-tools v0.16.0 // indirect
-	github.com/tidwall/gjson v1.18.0 // indirect
 	github.com/tidwall/match v1.1.1 // indirect
 	github.com/tidwall/pretty v1.2.0 // indirect
 	github.com/vbatts/tar-split v0.12.1 // indirect

examples/single-file-app-example/hooks/main.go

@@ -36,6 +36,12 @@ var config = &pkg.ApplicationHookConfig{
 }
 
 func Handle(_ context.Context, input *pkg.ApplicationHookInput) error {
+	enabled, ok := input.Settings.GetOk("apiServersDiscovery.enabled")
+	if !ok || !enabled.Bool() {
+		input.Logger.Info("apiServersDiscovery.enabled is not set — skipping")
+		return nil
+	}
+
 	podNames, err := objectpatch.UnmarshalToStruct[string](input.Snapshots, SnapshotKey)
 	if err != nil {
 		return err

examples/single-file-app-example/hooks/main_test.go

@@ -5,6 +5,7 @@ import (
 
 	. "github.com/onsi/ginkgo"
 	. "github.com/onsi/gomega"
+	"github.com/tidwall/gjson"
 
 	"github.com/deckhouse/deckhouse/pkg/log"
 
@@ -20,35 +21,57 @@ const (
 )
 
 var _ = Describe("handle hook single file example", func() {
-	snapshots := mock.NewSnapshotsMock(GinkgoT())
-	snapshots.GetMock.When(singlefileappexample.SnapshotKey).Then(
-		[]pkg.Snapshot{
-			mock.NewSnapshotMock(GinkgoT()).UnmarshalToMock.Set(func(v any) error {
-				str := v.(*string)
-				*str = firstSnapshot
-
-				return nil
-			}),
-			mock.NewSnapshotMock(GinkgoT()).UnmarshalToMock.Set(func(v any) error {
-				str := v.(*string)
-				*str = secondSnapshot
-
-				return nil
-			}),
-		},
-	)
-
-	values := mock.NewOutputPatchableValuesCollectorMock(GinkgoT())
-	values.SetMock.When("test.internal.apiServers", []string{firstSnapshot, secondSnapshot})
-
-	var input = &pkg.ApplicationHookInput{
-		Snapshots: snapshots,
-		Values:    values,
-		Logger:    log.NewNop(),
-	}
-
-	Context("reconcile func", func() {
-		It("reconcile func executed correctly", func() {
+	Context("settings gate closed", func() {
+		settings := mock.NewOutputPatchableValuesCollectorMock(GinkgoT())
+		settings.GetOkMock.When("apiServersDiscovery.enabled").Then(gjson.Result{}, false)
+
+		values := mock.NewOutputPatchableValuesCollectorMock(GinkgoT())
+
+		var input = &pkg.ApplicationHookInput{
+			Values:   values,
+			Settings: settings,
+			Logger:   log.NewNop(),
+		}
+
+		It("does not touch values when the gate is closed", func() {
+			err := singlefileappexample.Handle(context.Background(), input)
+			Expect(err).ShouldNot(HaveOccurred())
+		})
+	})
+
+	Context("settings gate open", func() {
+		snapshots := mock.NewSnapshotsMock(GinkgoT())
+		snapshots.GetMock.When(singlefileappexample.SnapshotKey).Then(
+			[]pkg.Snapshot{
+				mock.NewSnapshotMock(GinkgoT()).UnmarshalToMock.Set(func(v any) error {
+					str := v.(*string)
+					*str = firstSnapshot
+
+					return nil
+				}),
+				mock.NewSnapshotMock(GinkgoT()).UnmarshalToMock.Set(func(v any) error {
+					str := v.(*string)
+					*str = secondSnapshot
+
+					return nil
+				}),
+			},
+		)
+
+		settings := mock.NewOutputPatchableValuesCollectorMock(GinkgoT())
+		settings.GetOkMock.When("apiServersDiscovery.enabled").Then(gjson.Result{Type: gjson.True}, true)
+
+		values := mock.NewOutputPatchableValuesCollectorMock(GinkgoT())
+		values.SetMock.When("test.internal.apiServers", []string{firstSnapshot, secondSnapshot})
+
+		var input = &pkg.ApplicationHookInput{
+			Snapshots: snapshots,
+			Values:    values,
+			Settings:  settings,
+			Logger:    log.NewNop(),
+		}
+
+		It("writes discovered pods into values when the gate is open", func() {
 			err := singlefileappexample.Handle(context.Background(), input)
 			Expect(err).ShouldNot(HaveOccurred())
 		})

internal/executor/application.go

@@ -46,6 +46,18 @@ func (e *applicationExecutor) Execute(ctx context.Context, req Request) (Result,
 		return nil, fmt.Errorf("get patchable values: %w", err)
 	}
 
+	rawSettings, err := req.GetConfigValues()
+	if err != nil {
+		e.logger.Error("get settings", slog.String("error", err.Error()))
+		return nil, fmt.Errorf("get settings: %w", err)
+	}
+
+	patchableSettings, err := patchablevalues.NewPatchableValues(rawSettings)
+	if err != nil {
+		e.logger.Error("new patchable settings", slog.String("error", err.Error()))
+		return nil, fmt.Errorf("get patchable settings: %w", err)
+	}
+
 	bContext, err := req.GetBindingContexts()
 	if err != nil {
 		e.logger.Warn("get binding context", slog.String("error", err.Error()))
@@ -85,6 +97,7 @@ func (e *applicationExecutor) Execute(ctx context.Context, req Request) (Result,
 		Snapshots:        formattedSnapshots,
 		Instance:         inst,
 		Values:           patchableValues,
+		Settings:         patchableSettings,
 		PatchCollector:   namespacedPatchCollector,
 		MetricsCollector: metricsCollector,
 		DC:               dc,