// ProcessConfig replaces references of environment varialbes for the given data
// Support variable syntax: $varname, ${varname}
func ProcessConfig(data []byte, e *env.Env, escapeChar rune) ([]byte, error) {
var result []byte
var sc scanner.Scanner
sc.Init(bytes.NewReader(data))
DONE:
for {
switch ch := sc.Peek(); ch {
default:
result = append(result, byte(sc.Next()))
case scanner.EOF:
break DONE
case escapeChar:
curr, next := sc.Next(), sc.Peek()
if next != '$' {
result = append(result, byte(curr))
}
if next != scanner.EOF {
result = append(result, byte(sc.Next()))
}
case '$':
name, err := parseVariable(&sc)
if err != nil {
pos := sc.Pos()
return result, fmt.Errorf(`parseError:%d:%d: %v %q`, pos.Line, pos.Offset, err, name)
}
result = append(result, e.Get(string(name))...)
}
}
return result, nil
}
