Function consumeBody

lib/web/fetch/body.js:455–501

* @see https://fetch.spec.whatwg.org/#concept-body-consume-body * @param {any} object internal state * @param {(value: unknown) => unknown} convertBytesToJSValue * @param {any} instance * @param {(target: any) => any} getInternalState

(object, convertBytesToJSValue, instance, getInternalState)

 * @param {(target: any) => any} getInternalState
 */
function consumeBody (object, convertBytesToJSValue, instance, getInternalState) {
  try {
    webidl.brandCheck(object, instance)
  } catch (e) {
    return Promise.reject(e)
  }

  object = getInternalState(object)

  // 1. If object is unusable, then return a promise rejected
  //    with a TypeError.
  if (bodyUnusable(object)) {
    return Promise.reject(new TypeError('Body is unusable: Body has already been read'))
  }

  // 2. Let promise be a new promise.
  const promise = Promise.withResolvers()

  // 3. Let errorSteps given error be to reject promise with error.
  const errorSteps = promise.reject

  // 4. Let successSteps given a byte sequence data be to resolve
  //    promise with the result of running convertBytesToJSValue
  //    with data. If that threw an exception, then run errorSteps
  //    with that exception.
  const successSteps = (data) => {
    try {
      promise.resolve(convertBytesToJSValue(data))
    } catch (e) {
      errorSteps(e)
    }
  }

  // 5. If object’s body is null, then run successSteps with an
  //    empty byte sequence.
  if (object.body == null) {
    successSteps(Buffer.allocUnsafe(0))
    return promise.promise
  }

  // 6. Otherwise, fully read object’s body given successSteps,
  //    errorSteps, and object’s relevant global object.
  fullyReadBody(object.body, successSteps, errorSteps)

  // 7. Return promise.
  return promise.promise
}

/**
 * @see https://fetch.spec.whatwg.org/#body-unusable