XML to Crystal Converter

About this tool

Paste an XML sample and get Crystal type definitions you can use immediately. Emits classes including `JSON::Serializable`, with `@[JSON::Field]` where a key needs renaming.

When you would use it

• Crystal’s built-in JSON mapping
• Bootstrapping models from a real XML response instead of writing them by hand
• Keeping types in step with an API that has changed

Worked example

<?xml version="1.0" encoding="UTF-8"?>
<user id="4815">
  <name>Ada Lovelace</name>
  <active>true</active>
  <score>91.5</score>
  <roles>
    <role>admin</role>
    <role>editor</role>
  </roles>
</user>

require "json"
class Root
  include JSON::Serializable

  property user : User
end
class User
  include JSON::Serializable

  @[JSON::Field(key: "@id")]
  property id : Int64
  property name : String
  property active : Bool
  property score : Float64
  property roles : Roles
end
class Roles
  include JSON::Serializable

  property role : Array(String)
end

Things worth knowing

• Every object in an array is merged when inferring the shape, so a field missing from one item is marked optional rather than assumed to always be present.
• Identical nested shapes are de-duplicated into a single type instead of generating near-duplicates.
• Array element types are named from the singular of the field name, so posts produces a Post type.
• XML carries no type information, so numeric and boolean-looking text is inferred. Check the result where a value could legitimately be a string.