+
+// ResolveEnvVar Resolved environment variable regarding the syntax ${MYVAR}
+// or $MYVAR following by a slash or a backslash
+func ResolveEnvVar(s string) (string, error) {
+ if s == "" {
+ return s, nil
+ }
+
+ // Resolved tilde : ~/
+ if len(s) > 2 && s[:2] == "~/" {
+ if usr, err := user.Current(); err == nil {
+ s = filepath.Join(usr.HomeDir, s[2:])
+ }
+ }
+
+ // Resolved ${MYVAR}
+ re := regexp.MustCompile("\\${([^}]+)}")
+ vars := re.FindAllStringSubmatch(s, -1)
+ res := s
+ for _, v := range vars {
+ val := os.Getenv(v[1])
+ if val == "" {
+ return res, fmt.Errorf("ERROR: %s env variable not defined", v[1])
+ }
+
+ rer := regexp.MustCompile("\\${" + v[1] + "}")
+ res = rer.ReplaceAllString(res, val)
+ }
+
+ // Resolved $MYVAR following by a slash (or a backslash for Windows)
+ // TODO
+ //re := regexp.MustCompile("\\$([^\\/])+/")
+
+ return path.Clean(res), nil
+}