如何反复调用回调function？

Question

getData is a function that returns data from a third-party source. May return errors. key - a string to be passed to the callback function. maxRequestsNumber - max. the number of calls to the callback function. If this parameter is absent - repeat an infinite number of times. The getRepeatableData function should call getData and handle errors. If the getData call returns a NotFoundError, then we throw an exception. - If the call to getData returns a TemporaryError error, then we must make a repeated call to the callback function. The number of such calls should not exceed the value of maxRequestsNumber. If the number of repeated calls exceeds maxRequestsNumber, then the getRepeatableData function should throw an AttemtsLimitExceeded error.

If getData is executed without errors, the function should return what getData returned.

function getRepeatableData(getData, key, maxRequestsNumber) {
  try{
    const func = getData();
  }
  catch(e){
    if(e NotFoundError){
      throw e;
    }
    let number = 1;
    if(e == TemporaryError){
      const callFunc = function getData(key){
        if(number > maxRequestsNumber){
          return key;
        }
        return getData(maxRequestsNumber - 1);
      }
    }
    if (callFunc > maxRequestsNumber){
      throw AttemptsLimitExceeded;
    }
  }
  return getData();
}

Answer 1

If I'm understanding the question correctly, you're looking for something like this:

function foo(callback, maxStack) {
    let data = null;
    if (maxStack === 0) {
        throw AttemptsLimitError
    }
    try {
        data = callback();
    } catch(e) {
        if (e == UnrecoverableError) {
            throw e;
        else if (e == RecoverableError) {
            return foo(callback, maxStack === null ? null : maxStack - 1);
        }
    }
    return data;
}

The details are a little different but the concept is the same. Recursively try again and again until it either works or you reach the attempt limit.

Answer 2

Solved using recursion, please have a look

function getRepeatableData(getData, key, maxRequestsNumber) {
  let output;
  if (!maxRequestsNumber)
    throw AttemptsLimitExceeded;
  try{
    output = getData();
  }
  catch(e){
    if(e instanceof NotFoundError)
      throw e;
    else if(e instanceof TemporaryError)
      getRepeatableData(getData, key, maxRequestsNumber--)
  }
  return output
}