Updates a single user or adds the user if they don't exist

{
  "type": "object",
  "properties": {
    "customData": {
      "type": "string"
    },
    "email": {
      "type": "string"
    },
    "name": {
      "type": "string"
    },
    "type": {
      "type": "string"
    },
    "userId": {
      "type": "string"
    },
    "username": {
      "type": "string"
    }
  },
  "required": [
    "userId"
  ],
  "additionalProperties": false
}