class EachPromise in Auth0 Single Sign On 8.2
Represents a promise that iterates over many promises and invokes side-effect functions in the process.
Hierarchy
- class \GuzzleHttp\Promise\EachPromise implements PromisorInterface
Expanded class hierarchy of EachPromise
File
- vendor/
guzzlehttp/ promises/ src/ EachPromise.php, line 8
Namespace
GuzzleHttp\PromiseView source
class EachPromise implements PromisorInterface {
private $pending = [];
/** @var \Iterator */
private $iterable;
/** @var callable|int */
private $concurrency;
/** @var callable */
private $onFulfilled;
/** @var callable */
private $onRejected;
/** @var Promise */
private $aggregate;
/** @var bool */
private $mutex;
/**
* Configuration hash can include the following key value pairs:
*
* - fulfilled: (callable) Invoked when a promise fulfills. The function
* is invoked with three arguments: the fulfillment value, the index
* position from the iterable list of the promise, and the aggregate
* promise that manages all of the promises. The aggregate promise may
* be resolved from within the callback to short-circuit the promise.
* - rejected: (callable) Invoked when a promise is rejected. The
* function is invoked with three arguments: the rejection reason, the
* index position from the iterable list of the promise, and the
* aggregate promise that manages all of the promises. The aggregate
* promise may be resolved from within the callback to short-circuit
* the promise.
* - concurrency: (integer) Pass this configuration option to limit the
* allowed number of outstanding concurrently executing promises,
* creating a capped pool of promises. There is no limit by default.
*
* @param mixed $iterable Promises or values to iterate.
* @param array $config Configuration options
*/
public function __construct($iterable, array $config = []) {
$this->iterable = iter_for($iterable);
if (isset($config['concurrency'])) {
$this->concurrency = $config['concurrency'];
}
if (isset($config['fulfilled'])) {
$this->onFulfilled = $config['fulfilled'];
}
if (isset($config['rejected'])) {
$this->onRejected = $config['rejected'];
}
}
public function promise() {
if ($this->aggregate) {
return $this->aggregate;
}
try {
$this
->createPromise();
$this->iterable
->rewind();
$this
->refillPending();
} catch (\Throwable $e) {
$this->aggregate
->reject($e);
} catch (\Exception $e) {
$this->aggregate
->reject($e);
}
return $this->aggregate;
}
private function createPromise() {
$this->mutex = false;
$this->aggregate = new Promise(function () {
reset($this->pending);
if (empty($this->pending) && !$this->iterable
->valid()) {
$this->aggregate
->resolve(null);
return;
}
// Consume a potentially fluctuating list of promises while
// ensuring that indexes are maintained (precluding array_shift).
while ($promise = current($this->pending)) {
next($this->pending);
$promise
->wait();
if ($this->aggregate
->getState() !== PromiseInterface::PENDING) {
return;
}
}
});
// Clear the references when the promise is resolved.
$clearFn = function () {
$this->iterable = $this->concurrency = $this->pending = null;
$this->onFulfilled = $this->onRejected = null;
};
$this->aggregate
->then($clearFn, $clearFn);
}
private function refillPending() {
if (!$this->concurrency) {
// Add all pending promises.
while ($this
->addPending() && $this
->advanceIterator()) {
}
return;
}
// Add only up to N pending promises.
$concurrency = is_callable($this->concurrency) ? call_user_func($this->concurrency, count($this->pending)) : $this->concurrency;
$concurrency = max($concurrency - count($this->pending), 0);
// Concurrency may be set to 0 to disallow new promises.
if (!$concurrency) {
return;
}
// Add the first pending promise.
$this
->addPending();
// Note this is special handling for concurrency=1 so that we do
// not advance the iterator after adding the first promise. This
// helps work around issues with generators that might not have the
// next value to yield until promise callbacks are called.
while (--$concurrency && $this
->advanceIterator() && $this
->addPending()) {
}
}
private function addPending() {
if (!$this->iterable || !$this->iterable
->valid()) {
return false;
}
$promise = promise_for($this->iterable
->current());
$idx = $this->iterable
->key();
$this->pending[$idx] = $promise
->then(function ($value) use ($idx) {
if ($this->onFulfilled) {
call_user_func($this->onFulfilled, $value, $idx, $this->aggregate);
}
$this
->step($idx);
}, function ($reason) use ($idx) {
if ($this->onRejected) {
call_user_func($this->onRejected, $reason, $idx, $this->aggregate);
}
$this
->step($idx);
});
return true;
}
private function advanceIterator() {
// Place a lock on the iterator so that we ensure to not recurse,
// preventing fatal generator errors.
if ($this->mutex) {
return false;
}
$this->mutex = true;
try {
$this->iterable
->next();
$this->mutex = false;
return true;
} catch (\Throwable $e) {
$this->aggregate
->reject($e);
$this->mutex = false;
return false;
} catch (\Exception $e) {
$this->aggregate
->reject($e);
$this->mutex = false;
return false;
}
}
private function step($idx) {
// If the promise was already resolved, then ignore this step.
if ($this->aggregate
->getState() !== PromiseInterface::PENDING) {
return;
}
unset($this->pending[$idx]);
// Only refill pending promises if we are not locked, preventing the
// EachPromise to recursively invoke the provided iterator, which
// cause a fatal error: "Cannot resume an already running generator"
if ($this
->advanceIterator() && !$this
->checkIfFinished()) {
// Add more pending promises if possible.
$this
->refillPending();
}
}
private function checkIfFinished() {
if (!$this->pending && !$this->iterable
->valid()) {
// Resolve the promise if there's nothing left to do.
$this->aggregate
->resolve(null);
return true;
}
return false;
}
}
Members
Name | Modifiers | Type | Description | Overrides |
---|---|---|---|---|
EachPromise:: |
private | property | @var Promise | |
EachPromise:: |
private | property | @var callable|int | |
EachPromise:: |
private | property | @var \Iterator | |
EachPromise:: |
private | property | @var bool | |
EachPromise:: |
private | property | @var callable | |
EachPromise:: |
private | property | @var callable | |
EachPromise:: |
private | property | ||
EachPromise:: |
private | function | ||
EachPromise:: |
private | function | ||
EachPromise:: |
private | function | ||
EachPromise:: |
private | function | ||
EachPromise:: |
public | function |
Returns a promise. Overrides PromisorInterface:: |
|
EachPromise:: |
private | function | ||
EachPromise:: |
private | function | ||
EachPromise:: |
public | function | Configuration hash can include the following key value pairs: |