Optioned recursive environment variables expansion (#793)

* feat: add flag for disabling recursive environment variables expansion * chore: fill the cli documentation about new flag * chore: optimize flags
Praqma · May 26, 2023 · f0ddf48 · f0ddf48
1 parent 42f437b
commit f0ddf48
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Showing 4 changed files with 24 additions and 10 deletions.
diff --git a/docs/cmd_reference.md b/docs/cmd_reference.md
@@ -69,6 +69,9 @@ This lists available CMD options in Helmsman:
   `--no-env-subst`
         turn off environment substitution globally.
 
+  `--no-recursive-env-expand`
+        disable recursive environment variables expansion.
+
   `--subst-env-values`
         turn on environment substitution in values files.
 

diff --git a/internal/app/cli.go b/internal/app/cli.go
@@ -79,6 +79,7 @@ type cli struct {
 	diffContext           int
 	noEnvSubst            bool
 	substEnvValues        bool
+	noRecursiveEnvExpand  bool
 	noSSMSubst            bool
 	substSSMValues        bool
 	detailedExitCode      bool
@@ -138,6 +139,7 @@ func (c *cli) setup() {
 	flag.BoolVar(&c.detailedExitCode, "detailed-exit-code", false, "returns a detailed exit code (0 - no changes, 1 - error, 2 - changes present)")
 	flag.BoolVar(&c.noEnvSubst, "no-env-subst", false, "turn off environment substitution globally")
 	flag.BoolVar(&c.substEnvValues, "subst-env-values", false, "turn on environment substitution in values files.")
+	flag.BoolVar(&c.noRecursiveEnvExpand, "no-recursive-env-expand", false, "disable recursive environment values expansion")
 	flag.BoolVar(&c.noSSMSubst, "no-ssm-subst", false, "turn off SSM parameter substitution globally")
 	flag.BoolVar(&c.substSSMValues, "subst-ssm-values", false, "turn on SSM parameter substitution in values files.")
 	flag.BoolVar(&c.updateDeps, "update-deps", false, "run 'helm dep up' for local charts")
@@ -231,6 +233,11 @@ func (c *cli) parse() {
 			log.Verbose("Substitution of env variables in values enabled")
 		}
 	}
+
+	if !c.noRecursiveEnvExpand {
+		log.Verbose("Recursive environment variables expansion is enabled")
+	}
+
 	if !c.noSSMSubst {
 		log.Verbose("Substitution of SSM variables enabled")
 		if c.substSSMValues {

diff --git a/internal/app/main.go b/internal/app/main.go
@@ -8,7 +8,7 @@ import (
 const (
 	helmBin            = "helm"
 	kubectlBin         = "kubectl"
-	appVersion         = "v3.16.4"
+	appVersion         = "v3.16.4-fix"
 	tempFilesDir       = ".helmsman-tmp"
 	defaultContextName = "default"
 	resourcePool       = 10

diff --git a/internal/app/utils.go b/internal/app/utils.go
@@ -146,8 +146,10 @@ func readFile(filepath string) string {
 // recusively expanding the variable's value
 func getEnv(key string) string {
 	value := os.Getenv(key)
-	for envVar.MatchString(value) {
-		value = os.ExpandEnv(value)
+	if !flags.noRecursiveEnvExpand {
+		for envVar.MatchString(value) {
+			value = os.ExpandEnv(value)
+		}
 	}
 	return value
 }
@@ -160,13 +162,15 @@ func prepareEnv(envFiles []string) error {
 			return fmt.Errorf("error loading env file: %w", err)
 		}
 	}
-	for _, e := range os.Environ() {
-		if !strings.Contains(e, "$") {
-			continue
+	if !flags.noRecursiveEnvExpand {
+		for _, e := range os.Environ() {
+			if !strings.Contains(e, "$") {
+				continue
+			}
+			e = os.Expand(e, getEnv)
+			pair := strings.SplitN(e, "=", 2)
+			os.Setenv(pair[0], pair[1])
 		}
-		e = os.Expand(e, getEnv)
-		pair := strings.SplitN(e, "=", 2)
-		os.Setenv(pair[0], pair[1])
 	}
 	return nil
 }
@@ -178,7 +182,7 @@ func substituteEnv(str string) string {
 	if strings.Contains(str, "$") {
 		// add $$ escaping for $ strings
 		os.Setenv("HELMSMAN_DOLLAR", "$")
-		return os.ExpandEnv(strings.ReplaceAll(str, "$$", "${HELMSMAN_DOLLAR}"))
+		return os.Expand(strings.ReplaceAll(str, "$$", "${HELMSMAN_DOLLAR}"), getEnv)
 	}
 	return str
 }