feat: `helmfile --log-level=debug apply --retain-values-files` (#1127)

`--retain-values-files` prevents temporary values files that were passed to Helm commands run by Helmfile for debugging purpose.

With that, you can manually rerun helm commands that were logged when `--log-level=debug` is enabled.

Resolves ##1117

main.go

@@ -338,6 +338,10 @@ func main() {
 					Value: "",
 					Usage: "pass args to helm exec",
 				},
+				cli.BoolFlag{
+					Name:  "retain-values-files",
+					Usage: "Stop cleaning up values files passed to Helm. Together with --log-level=debug, you can manually rerun helm commands as Helmfile did for debugging purpose",
+				},
 				cli.BoolFlag{
 					Name:  "suppress-secrets",
 					Usage: "suppress secrets in the diff output. highly recommended to specify on CI/CD use-cases",
@@ -542,6 +546,10 @@ func (c configImpl) DetailedExitcode() bool {
 	return c.c.Bool("detailed-exitcode")
 }
 
+func (c configImpl) RetainValuesFiles() bool {
+	return c.c.Bool("retain-values-files")
+}
+
 func (c configImpl) SuppressSecrets() bool {
 	return c.c.Bool("suppress-secrets")
 }

pkg/app/app.go

@@ -155,7 +155,7 @@ func (a *App) Apply(c ApplyConfigProvider) error {
 		mut.Unlock()
 
 		return matched, errs
-	})
+	}, c.RetainValuesFiles())
 
 	if err != nil {
 		return err
@@ -343,7 +343,7 @@ func (a *App) visitStates(fileOrDir string, defOpts LoadOpts, converge func(*sta
 			sig := <-sigs
 
 			errs := []error{fmt.Errorf("Received [%s] to shutdown ", sig)}
-			_ = context{a, st}.clean(errs)
+			_ = context{app: a, st: st, retainValues: defOpts.RetainValuesFiles}.clean(errs)
 			// See http://tldp.org/LDP/abs/html/exitcodes.html
 			switch sig {
 			case syscall.SIGINT:
@@ -353,7 +353,7 @@ func (a *App) visitStates(fileOrDir string, defOpts LoadOpts, converge func(*sta
 			}
 		}()
 
-		ctx := context{a, st}
+		ctx := context{app: a, st: st, retainValues: defOpts.RetainValuesFiles}
 
 		helm := a.helmExecer
 
@@ -409,7 +409,7 @@ func (a *App) visitStates(fileOrDir string, defOpts LoadOpts, converge func(*sta
 		processed, errs := converge(templated, helm)
 		noMatchInHelmfiles = noMatchInHelmfiles && !processed
 
-		return context{a, templated}.clean(errs)
+		return context{app: a, st: templated, retainValues: defOpts.RetainValuesFiles}.clean(errs)
 	})
 
 	if err != nil {
@@ -434,12 +434,12 @@ func (a *App) ForEachStateFiltered(do func(*Run) []error) error {
 	return err
 }
 
-func (a *App) ForEachState(do func(*Run) (bool, []error)) error {
+func (a *App) ForEachState(do func(*Run) (bool, []error), retainValues ...bool) error {
 	ctx := NewContext()
 	err := a.visitStatesWithSelectorsAndRemoteSupport(a.FileOrDir, func(st *state.HelmState, helm helmexec.Interface) (bool, []error) {
 		run := NewRun(st, helm, ctx)
 		return do(run)
-	})
+	}, retainValues...)
 
 	return err
 }
@@ -511,11 +511,15 @@ type Opts struct {
 	DAGEnabled bool
 }
 
-func (a *App) visitStatesWithSelectorsAndRemoteSupport(fileOrDir string, converge func(*state.HelmState, helmexec.Interface) (bool, []error)) error {
+func (a *App) visitStatesWithSelectorsAndRemoteSupport(fileOrDir string, converge func(*state.HelmState, helmexec.Interface) (bool, []error), retainValues ...bool) error {
 	opts := LoadOpts{
 		Selectors: a.Selectors,
 	}
 
+	if len(retainValues) > 0 {
+		opts.RetainValuesFiles = retainValues[0]
+	}
+
 	envvals := []interface{}{}
 
 	if a.ValuesFiles != nil {
@@ -1222,10 +1226,12 @@ func (c context) clean(errs []error) error {
 		errs = []error{}
 	}
 
+	if !c.retainValues {
 		cleanErrs := c.st.Clean()
 		if cleanErrs != nil {
 			errs = append(errs, cleanErrs...)
 		}
+	}
 
 	return c.wrapErrs(errs...)
 }
@@ -1233,6 +1239,8 @@ func (c context) clean(errs []error) error {
 type context struct {
 	app *App
 	st  *state.HelmState
+
+	retainValues bool
 }
 
 func (c context) wrapErrs(errs ...error) error {

pkg/app/app_test.go

@@ -1892,6 +1892,7 @@ func (c configImpl) Concurrency() int {
 type applyConfig struct {
 	args              string
 	values            []string
+	retainValuesFiles bool
 	set               []string
 	skipDeps          bool
 	suppressSecrets   bool
@@ -1952,6 +1953,10 @@ func (a applyConfig) Logger() *zap.SugaredLogger {
 	return a.logger
 }
 
+func (a applyConfig) RetainValuesFiles() bool {
+	return a.retainValuesFiles
+}
+
 // Mocking the command-line runner
 
 type mockRunner struct {

pkg/app/config.go

@@ -48,6 +48,8 @@ type ApplyConfigProvider interface {
 	NoColor() bool
 	Context() int
 
+	RetainValuesFiles() bool
+
 	concurrencyConfig
 	interactive
 	loggingConfig

pkg/app/load_opts.go

@@ -9,6 +9,8 @@ type LoadOpts struct {
 	Selectors   []string
 	Environment state.SubhelmfileEnvironmentSpec
 
+	RetainValuesFiles bool
+
 	// CalleePath is the absolute path to the file being loaded
 	CalleePath string
 }