Developer
<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\HttpFoundation;
/**
* StreamedResponse represents a streamed HTTP response.
*
* A StreamedResponse uses a callback for its content.
*
* The callback should use the standard PHP functions like echo
* to stream the response back to the client. The flush() function
* can also be used if needed.
*
* @see flush()
*
* @author Fabien Potencier <fabien@symfony.com>
*/
class StreamedResponse extends Response
{
protected $callback;
protected $streamed;
private bool $headersSent;
public function __construct(callable $callback = null, int $status = 200, array $headers = [])
{
parent::__construct(null, $status, $headers);
if (null !== $callback) {
$this->setCallback($callback);
}
$this->streamed = false;
$this->headersSent = false;
}
/**
* Sets the PHP callback associated with this Response.
*
* @return $this
*/
public function setCallback(callable $callback): static
{
$this->callback = $callback;
return $this;
}
/**
* {@inheritdoc}
*
* This method only sends the headers once.
*
* @return $this
*/
public function sendHeaders(): static
{
if ($this->headersSent) {
return $this;
}
$this->headersSent = true;
return parent::sendHeaders();
}
/**
* {@inheritdoc}
*
* This method only sends the content once.
*
* @return $this
*/
public function sendContent(): static
{
if ($this->streamed) {
return $this;
}
$this->streamed = true;
if (null === $this->callback) {
throw new \LogicException('The Response callback must not be null.');
}
($this->callback)();
return $this;
}
/**
* {@inheritdoc}
*
* @throws \LogicException when the content is not null
*
* @return $this
*/
public function setContent(?string $content): static
{
if (null !== $content) {
throw new \LogicException('The content cannot be set on a StreamedResponse instance.');
}
$this->streamed = true;
return $this;
}
/**
* {@inheritdoc}
*/
public function getContent(): string|false
{
return false;
}
}
Developer
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