encoding a Map[String, String] should encode keys and values as Yaml Strings, even if some of them look like Ints or other scalars

[adriaanm]

Example:

scala> Map("a" -> "1").asYaml
val res6: String = "a: 1
"

I would expect the yaml to be

a : "1"

as with #220, this is problematic in kubernetes when encoding e.g. maps of labels.

I managed a workaround for now: s"\"${value}\"".asNode, but it would be nice if

  object ScalarNode {
    def apply(value: String): ScalarNode = new ScalarNode(value, Tag.resolveTag(value))

could be generalised a bit so we can pass the style argument to resolveTag (at least).

However, I would argue that when you encode a Map[String, String] you should only get Yaml Strings in your values. For a Map[String, Any] I could imagine wanting to resolve the tags.

[lbialy]

Hey Adriaan, it's a more general problem in scala-yaml from what I recall as the initial type was not passed down into the scalars at all. I think I did introduce that for one case and left generalisation of that for a later refactor that did not happen yet (because it should always try to pass what the type was of the thing that got converted into a scalar node so roundtrips yield exactly the same thing).

[adriaanm]

Thanks for taking a look, @lbialy :-) I wouldn't mind creating the AST nodes directly with the explicit types, as I would love to use this over raw yaml, and my devious workaround actually doesn't work (yet):

s"\"1\"".asNode.map(_.asYaml)
val res8: Either[org.virtuslab.yaml.YamlError, String] = Right(1
)

I'll keep looking for a workaround, any hints appreciated :-)

[adriaanm]

Ah, then I saw

// todo escape string using doublequotes
if (tag.contains(Tag.nullTag)) sb.append("!!null")
else sb.append(value)

so now I have this beautiful hack:

  def encodeStringMap(nodes: Map[String, String]): Node = {
    val mappings: Map[Node, Node] = nodes.map { case (key, value) =>
      Node.ScalarNode(key) -> Node.ScalarNode(s"\"$value\"")
    }
    Node.MappingNode(mappings)
  }

(I just have to encode labels for the yaml in a ConfigGroup)