export class Request 
{
  
  static async getJSON<O>(url: string): Promise<O> 
  {
    let result = await fetch( url, 
      {
        method: 'GET',
        headers: { 'Accept': 'application/json' }
      }
    );

    if ( ! result.ok ) 
    {
      throw new Error( `GET ${url} failed: ${result.status} ${result.statusText}` );
    }

    return result.json() as Promise<O>;
  }

  static async postJSON<I, O>(url: string, input: I): Promise<O> 
  {
    let result = await fetch(
      url, 
      {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'Accept': 'application/json'
      },
      body: JSON.stringify( input )
    });

    if ( ! result.ok ) 
    {
      throw new Error( `POST ${url} failed: ${result.status} ${result.statusText}` );
    }

    return result.json() as Promise<O>;
  }
}