aboutsummaryrefslogtreecommitdiff
path: root/yamlesque-spray-json/src/main/scala/formats.scala
blob: 81f86d2e5c5ebceb35c2994d3ec8aaa137db5a76 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
package yamlesque

import spray.json._

trait JsonYamlFormats {

  implicit def jsonToYamlReader[A](
      implicit jsReader: JsonReader[A]): YamlReader[A] = new YamlReader[A] {
    override def read(yaml: YamlValue): A =
      jsReader.read(JsonFormats.yamlToJson(yaml))
  }

  implicit def jsonToYamlWriter[A](
      implicit jsWriter: JsonWriter[A]): YamlWriter[A] = new YamlWriter[A] {
    override def write(a: A): YamlValue =
      JsonFormats.jsonToYaml(jsWriter.write(a))
  }

}

object JsonFormats {

  def jsonToYaml(js: JsValue): YamlValue = js match {
    case JsNull            => YamlEmpty
    case JsNumber(number)  => YamlScalar(number.toString)
    case JsBoolean(value)  => YamlScalar(value.toString)
    case JsString(value)   => YamlScalar(value)
    case JsArray(elements) => YamlSequence(elements.map(jsonToYaml _))
    case JsObject(fields)  => YamlMapping(fields.mapValues(jsonToYaml _))
  }

  val JsNumberPattern = """([-+]?[0-9]*\.?[0-9]+(?:[eE][-+]?[0-9]+)?)""".r

  def yamlToJson(yaml: YamlValue): JsValue = yaml match {
    case YamlEmpty                      => JsNull
    case YamlScalar("true")             => JsTrue
    case YamlScalar("false")            => JsFalse
    case YamlScalar(JsNumberPattern(x)) => JsNumber(x.toDouble)
    case YamlScalar(x)                  => JsString(x)
    case YamlSequence(elements)         => JsArray(elements.map(yamlToJson))
    case YamlMapping(fields)            => JsObject(fields.mapValues(yamlToJson))
  }

}