Add validation of updateStrategy parameter and unit test

Signed-off-by: Simon Bouchard <sbouchard@rbbn.com>

pkg/app/app_test.go

@@ -220,6 +220,97 @@ releases:
 	}
 }
 
+func TestUpdateStrategyParamValidation(t *testing.T) {
+	cases := []struct {
+		files          map[string]string
+		updateStrategy string
+		isValid        bool
+	}{
+		{map[string]string{
+			"/path/to/helmfile.yaml": `releases:
+- name: zipkin
+  chart: stable/zipkin
+  updateStrategy: reinstall
+`},
+			"reinstall",
+			true},
+		{map[string]string{
+			"/path/to/helmfile.yaml": `releases:
+- name: zipkin
+  chart: stable/zipkin
+  updateStrategy: reinstallIfForbidden
+`},
+			"reinstallIfForbidden",
+			true},
+		{map[string]string{
+			"/path/to/helmfile.yaml": `releases:
+- name: zipkin
+  chart: stable/zipkin
+  updateStrategy:
+`},
+			"",
+			true},
+		{map[string]string{
+			"/path/to/helmfile.yaml": `releases:
+- name: zipkin
+  chart: stable/zipkin
+  updateStrategy: foo
+`},
+			"foo",
+			false},
+		{map[string]string{
+			"/path/to/helmfile.yaml": `releases:
+- name: zipkin
+  chart: stable/zipkin
+  updateStrategy: reinstal
+`},
+			"reinstal",
+			false},
+		{map[string]string{
+			"/path/to/helmfile.yaml": `releases:
+- name: zipkin
+  chart: stable/zipkin
+  updateStrategy: reinstall1
+`},
+			"reinstall1",
+			false},
+	}
+
+	for idx, c := range cases {
+		fs := testhelper.NewTestFs(c.files)
+		app := &App{
+			OverrideHelmBinary:  DefaultHelmBinary,
+			OverrideKubeContext: "default",
+			Logger:              newAppTestLogger(),
+			Namespace:           "",
+			Env:                 "default",
+			FileOrDir:           "helmfile.yaml",
+		}
+
+		expectNoCallsToHelm(app)
+
+		app = injectFs(app, fs)
+
+		err := app.ForEachState(
+			Noop,
+			false,
+			SetFilter(true),
+		)
+
+		if c.isValid && err != nil {
+			t.Errorf("[case: %d] Unexpected error for valid case: %v", idx, err)
+		} else if !c.isValid {
+			var invalidUpdateStrategy state.InvalidUpdateStrategyError
+			invalidUpdateStrategy.UpdateStrategy = c.updateStrategy
+			if err == nil {
+				t.Errorf("[case: %d] Expected error for invalid case", idx)
+			} else if !strings.Contains(err.Error(), invalidUpdateStrategy.Error()) {
+				t.Errorf("[case: %d] Unexpected error returned for invalid case\ngot: %v\nexpected underlying error: %s", idx, err, invalidUpdateStrategy.Error())
+			}
+		}
+	}
+}
+
 func TestVisitDesiredStatesWithReleasesFiltered_Issue1008_MissingNonDefaultEnvInBase(t *testing.T) {
 	files := map[string]string{
 		"/path/to/base.yaml": `

pkg/app/desired_state_file_loader.go

@@ -5,6 +5,7 @@ import (
 	"errors"
 	"fmt"
 	"path/filepath"
+	"slices"
 
 	"dario.cat/mergo"
 	"github.com/helmfile/vals"
@@ -285,6 +286,18 @@ func (ld *desiredStateLoader) load(env, overrodeEnv *environment.Environment, ba
 		}
 	}
 
+	// Validate updateStrategy value if set in the releases
+	for i := range finalState.Releases {
+		if finalState.Releases[i].UpdateStrategy != "" {
+			if !slices.Contains(state.ValidUpdateStrategyValues, finalState.Releases[i].UpdateStrategy) {
+				return nil, &state.StateLoadError{
+					Msg:   fmt.Sprintf("failed to read %s", finalState.FilePath),
+					Cause: &state.InvalidUpdateStrategyError{UpdateStrategy: finalState.Releases[i].UpdateStrategy},
+				}
+			}
+		}
+	}
+
 	finalState.OrginReleases = finalState.Releases
 	return finalState, nil
 }

pkg/state/create.go

@@ -26,6 +26,8 @@ const (
 	DefaultHCLFileExtension = ".hcl"
 )
 
+var ValidUpdateStrategyValues = []string{UpdateStrategyReinstall, UpdateStrategyReinstallIfForbidden}
+
 type StateLoadError struct {
 	Msg   string
 	Cause error
@@ -43,6 +45,14 @@ func (e *UndefinedEnvError) Error() string {
 	return fmt.Sprintf("environment \"%s\" is not defined", e.Env)
 }
 
+type InvalidUpdateStrategyError struct {
+	UpdateStrategy string
+}
+
+func (e *InvalidUpdateStrategyError) Error() string {
+	return fmt.Sprintf("updateStrategy %q is invalid, valid values are: %s or not set", e.UpdateStrategy, strings.Join(ValidUpdateStrategyValues, ", "))
+}
+
 type StateCreator struct {
 	logger *zap.SugaredLogger
 

pkg/state/state.go

@@ -43,6 +43,10 @@ const (
 	// This is used by an interim solution to make the urfave/cli command report to the helmfile internal about that the
 	// --timeout flag is missingl
 	EmptyTimeout = -1
+
+	// Valid enum for updateStrategy values
+	UpdateStrategyReinstall            = "reinstall"
+	UpdateStrategyReinstallIfForbidden = "reinstallIfForbidden"
 )
 
 // ReleaseSetSpec is release set spec