in anghammarad/src/main/scala/com/gu/anghammarad/serialization/Serialization.scala [95:103]
def parseAllMappings(jsonStr: String): Try[List[Mapping]] = {
val allMappings = for {
json <- parse(jsonStr)
rawMappings <- json.hcursor.downField("mappings").as[List[Json]]
mappings <- rawMappings.traverseT(parseMapping).toEither
} yield mappings
allMappings.toTry
}