Read env variables from KfDef Parameters

pkg/kfapp/kustomize/kustomize.go

@@ -26,6 +26,7 @@ import (
 	"os"
 	"path"
 	"path/filepath"
+	"regexp"
 	"strconv"
 	"strings"
 	"time"
@@ -846,7 +847,7 @@ func MergeKustomization(compDir string, targetDir string, kfDef *kfconfig.KfConf
 
 	paramMap := make(map[string]string)
 	for _, nv := range params {
-		paramMap[nv.Name] = nv.Value
+		paramMap[nv.Name] = getParameterValue(nv.Value)
 	}
 	updateParamFiles := func() error {
 		paramFile := filepath.Join(targetDir, kftypesv3.KustomizationParamFile)
@@ -1462,3 +1463,23 @@ func GenerateYamlWithOperatorAnnotation(resMap resmap.ResMap, instance *unstruct
 	}
 	return buf.Bytes(), nil
 }
+
+func getParameterValue(value string) string {
+	// Check if there is a environment variable
+	// Supported format: $VAR and ${VAR}
+	var re = regexp.MustCompile(`(?m)^\$({(.*)}|\w)`)
+	envVariable := ""
+	if re.Match([]byte(value)){
+		if strings.HasPrefix(value, "${"){
+			envVariable = value[2:len(value)-1]
+		}else if strings.HasPrefix(value, "$") {
+			envVariable = value[1:]
+		}
+		return os.Getenv(envVariable)
+
+	}else{
+		log.Info("env variables are not used or are invalid in the parameters." +
+			" Supported Usage: $VAR and ${VAR}")
+	}
+	return value
+}

pkg/kfapp/kustomize/kustomize_test.go

@@ -213,3 +213,54 @@ func TestCreateStackAppKustomization(t *testing.T) {
 		}
 	}
 }
+
+
+func TestGetParameterValue(t *testing.T) {
+	type testCase struct {
+		Name     string
+		Input    string
+		Expected string
+	}
+	// Set EXAMPLE_VAR env variable
+	err := os.Setenv("EXAMPLE_VAR", "example")
+	if err !=nil {
+		t.Fatalf("Error setting env variable: %v", err)
+	}
+
+	testCases := []testCase{
+		{
+			Name:     "Input env variable of type $VAR",
+			Input:    "$EXAMPLE_VAR",
+			Expected: "example",
+		},
+		{
+			Name:     "Input env variable of type ${VAR}",
+			Input:    "${EXAMPLE_VAR}",
+			Expected: "example",
+		},
+		{
+			Name:     "Input string without env variable",
+			Input:    "example",
+			Expected: "example",
+		},
+	}
+
+	for _, c := range testCases {
+
+		t.Log(c.Name)
+		result := getParameterValue(c.Input)
+
+		if diff := cmp.Diff(c.Expected, result); diff != "" {
+			t.Fatalf("Result string is different from expected. (-want, +got):\n%s", diff)
+		}
+
+	}
+
+	// Unset the env variable
+	err = os.Unsetenv("EXAMPLE_VAR")
+	if err !=nil {
+		t.Fatalf("Error unsetting env variable: %v", err)
+	}
+
+
+}