You are here

PromiseInterface.php in Zircon Profile 8.0

Namespace

GuzzleHttp\Promise

File

vendor/guzzlehttp/promises/src/PromiseInterface.php
View source
<?php

namespace GuzzleHttp\Promise;


/**
 * A promise represents the eventual result of an asynchronous operation.
 *
 * The primary way of interacting with a promise is through its then method,
 * which registers callbacks to receive either a promise’s eventual value or
 * the reason why the promise cannot be fulfilled.
 *
 * @link https://promisesaplus.com/
 */
interface PromiseInterface {
  const PENDING = 'pending';
  const FULFILLED = 'fulfilled';
  const REJECTED = 'rejected';

  /**
   * Appends fulfillment and rejection handlers to the promise, and returns
   * a new promise resolving to the return value of the called handler.
   *
   * @param callable $onFulfilled Invoked when the promise fulfills.
   * @param callable $onRejected  Invoked when the promise is rejected.
   *
   * @return PromiseInterface
   */
  public function then(callable $onFulfilled = null, callable $onRejected = null);

  /**
   * Appends a rejection handler callback to the promise, and returns a new
   * promise resolving to the return value of the callback if it is called,
   * or to its original fulfillment value if the promise is instead
   * fulfilled.
   *
   * @param callable $onRejected Invoked when the promise is rejected.
   *
   * @return PromiseInterface
   */
  public function otherwise(callable $onRejected);

  /**
   * Get the state of the promise ("pending", "rejected", or "fulfilled").
   *
   * The three states can be checked against the constants defined on
   * PromiseInterface: PENDING, FULFILLED, and REJECTED.
   *
   * @return string
   */
  public function getState();

  /**
   * Resolve the promise with the given value.
   *
   * @param mixed $value
   * @throws \RuntimeException if the promise is already resolved.
   */
  public function resolve($value);

  /**
   * Reject the promise with the given reason.
   *
   * @param mixed $reason
   * @throws \RuntimeException if the promise is already resolved.
   */
  public function reject($reason);

  /**
   * Cancels the promise if possible.
   *
   * @link https://github.com/promises-aplus/cancellation-spec/issues/7
   */
  public function cancel();

  /**
   * Waits until the promise completes if possible.
   *
   * Pass $unwrap as true to unwrap the result of the promise, either
   * returning the resolved value or throwing the rejected exception.
   *
   * If the promise cannot be waited on, then the promise will be rejected.
   *
   * @param bool $unwrap
   *
   * @return mixed
   * @throws \LogicException if the promise has no wait function or if the
   *                         promise does not settle after waiting.
   */
  public function wait($unwrap = true);

}

Interfaces

Namesort descending Description
PromiseInterface A promise represents the eventual result of an asynchronous operation.