creating a json structure

I am using fusionAuth. The way it works is that I need to create a json structure called a request, Here is an example of one. Any idea how to create one in CI? 

Code:

{
  "applicationId": "10000000-0000-0002-0000-000000000001",
  "loginId": "[email protected]",
  "state": {
    "client_id": "10000000-0000-0002-0000-000000000001",
    "redirect_uri": "https://piedpiper.com/callback",
    "response_type": "code",
    "scope": "openid",
    "state": "CSRF123"
  }
}

proof that an old dog can learn new tricks