[v9.4.x] Provisioning: Parse boolean and numeric values from environment variables (#63192)

Provisioning: Parse boolean and numeric values from environment variables (#63085)

(cherry picked from commit a33e316f40)

Co-authored-by: Andres Martinez Gotor <andres.martinez@grafana.com>

pkg/services/provisioning/values/values.go

@@ -247,7 +247,7 @@ func transformInterface(i interface{}) (interface{}, interface{}, error) {
 	case reflect.Map:
 		return transformMap(i.(map[string]interface{}))
 	case reflect.String:
-		return interpolateValue(i.(string))
+		return interpolateIfaceValue(i.(string))
 	default:
 		// Was int, float or some other value that we do not need to do any transform on.
 		return i, i, nil
@@ -281,6 +281,34 @@ func transformMap(i map[string]interface{}) (interface{}, interface{}, error) {
 	return transformed, raw, nil
 }
 
+func interpolateIfaceValue(val string) (interface{}, string, error) {
+	parts := strings.Split(val, "$$")
+	if len(parts) > 1 {
+		return interpolateValue(val)
+	}
+	expanded, err := setting.ExpandVar(val)
+	if err != nil {
+		return val, val, fmt.Errorf("failed to interpolate value '%s': %w", val, err)
+	}
+	expandedEnv := os.ExpandEnv(expanded)
+	if expandedEnv != val {
+		// If the value is an environment variable, consider it may not be a string
+		intV, err := strconv.ParseInt(expandedEnv, 10, 64)
+		if err == nil {
+			return intV, val, nil
+		}
+		floatV, err := strconv.ParseFloat(expandedEnv, 64)
+		if err == nil {
+			return floatV, val, nil
+		}
+		boolV, err := strconv.ParseBool(expandedEnv)
+		if err == nil {
+			return boolV, val, nil
+		}
+	}
+	return expandedEnv, val, nil
+}
+
 // interpolateValue returns the final value after interpolation. In addition to environment variable interpolation,
 // expanders available for the settings file are expanded here.
 // For a literal '$', '$$' can be used to avoid interpolation.