Dictionary Key Order in Swift 4 JSONEncoder

Question

Is it possible to configure the Swift JSON encoder to use the sort order of the struct properties as the sort order of the dictionary keys in the JSON output? By default it uses some arbitrary (but seemingly not random) order, e.g. ...

struct Example: Codable {
  let id: Int
  let name: String
  let createdAt: Date
  let comments: [String]
}

... results in ...

"example" : {
  "id" : 1,
  "name" : "Test",
  "comments" : [
    "Comment 1",
    "Comment 2"
  ],
  "createdAt" : 549539643.25327206
}

I know that semantically the order doesn't matter, but I'd like to keep it for debugging purposes.

Answer 1

JSONEncoder has outputFormatting property, you can do this,

let encoder = JSONEncoder()
encoder.outputFormatting = .sortedKeys

I've not tried it, please try and let me know.