HTTP Post with no body in Angular

Looks like this is the appropriate answer:

postRequest(id) {
  this.http.post('/api?data=' + id, null).map(
    (response) => {
      return response;
    }
  )
}

Go to definition of POST method using your IDE and you can see passing either body: any | null are the available inputs

post(url: string, body: any | null, options: {
    headers?: HttpHeaders | {
        [header: string]: string | string[];
    };