微信小程序异步接口 Promise 化封装与上下文处理

/**
 * @function promise - 将 wx 接口 promise 化
 * 
 * @param { String|Function } wxApi - 需要转换的接口/接口名
 * @param { Object|Any } [originParam = {}] - 原接口要求的参数对象
 * @param { Object|Any } [extra] - 接口要求的其他参数
 */
function promise(wxApi, originParam = {}, extra){
 const api = wxApi instanceof Function?
  wxApi:
  wx[wxApi];

 return new Promise((done, fail) =>
  api(Object.assign(
   originParam,
   {
    success: done,
    failed: fail
   }
  ),
  extra)
 );
}

/**
 * @function promise - 将 wx 接口 promise 化
 * 
 * @param { String|Function } wxApi - 需要转换的接口/接口名
 * @param { Object|Any } [originParam = {}] - 原接口要求的参数对象
 * @param { Object|Any } [context = wx] - 执行上下文
 * @param { Object|Any } [extra] - 接口要求的其他参数
 */
function promise(wxApi, originParam = {}, context = wx, extra){
 const api = wxApi instanceof Function?
  wxApi:
  context[wxApi];

 return new Promise((done, fail) =>
  api.call(context, Object.assign(
   originParam,
   {
    success: done,
    failed: fail
   }
  ),
  extra)
 );
}

/**
 * @function takePhoto - promise风格的拍照接口
 * 
 * @param { Object|Any } [options = {}] - 相机配置
 * 
 * @return {Promise}
 */
export function takePhoto(options = {}){
  const tempOptions = {
    quality: 'high',
    ...options
  }

 const cameraContext = createCameraContext();

 return promise(cameraContext.takePhoto, tempOptions, cameraContext);
}