Developer
<?php
declare(strict_types=1);
namespace GuzzleHttp\Psr7;
use Psr\Http\Message\StreamInterface;
/**
* Compose stream implementations based on a hash of functions.
*
* Allows for easy testing and extension of a provided stream without needing
* to create a concrete class for a simple extension point.
*/
#[\AllowDynamicProperties]
final class FnStream implements StreamInterface
{
private const SLOTS = [
'__toString', 'close', 'detach', 'rewind',
'getSize', 'tell', 'eof', 'isSeekable', 'seek', 'isWritable', 'write',
'isReadable', 'read', 'getContents', 'getMetadata',
];
/** @var array<string, callable> */
private $methods;
/**
* @param array<string, callable> $methods Hash of method name to a callable.
*/
public function __construct(array $methods)
{
$this->methods = $methods;
// Create the functions on the class
foreach ($methods as $name => $fn) {
$this->{'_fn_'.$name} = $fn;
}
}
/**
* Lazily determine which methods are not implemented.
*
* @throws \BadMethodCallException
*/
public function __get(string $name): void
{
throw new \BadMethodCallException(str_replace('_fn_', '', $name)
.'() is not implemented in the FnStream');
}
/**
* The close method is called on the underlying stream only if possible.
*/
public function __destruct()
{
if (isset($this->_fn_close)) {
($this->_fn_close)();
}
}
/**
* An unserialize would allow the __destruct to run when the unserialized value goes out of scope.
*
* @throws \LogicException
*/
public function __wakeup(): void
{
throw new \LogicException('FnStream should never be unserialized');
}
/**
* Adds custom functionality to an underlying stream by intercepting
* specific method calls.
*
* @param StreamInterface $stream Stream to decorate
* @param array<string, callable> $methods Hash of method name to a closure
*
* @return FnStream
*/
public static function decorate(StreamInterface $stream, array $methods)
{
// If any of the required methods were not provided, then simply
// proxy to the decorated stream.
foreach (array_diff(self::SLOTS, array_keys($methods)) as $diff) {
/** @var callable $callable */
$callable = [$stream, $diff];
$methods[$diff] = $callable;
}
return new self($methods);
}
public function __toString(): string
{
try {
/** @var string */
return ($this->_fn___toString)();
} catch (\Throwable $e) {
if (\PHP_VERSION_ID >= 70400) {
throw $e;
}
trigger_error(sprintf('%s::__toString exception: %s', self::class, (string) $e), E_USER_ERROR);
return '';
}
}
public function close(): void
{
($this->_fn_close)();
}
public function detach()
{
return ($this->_fn_detach)();
}
public function getSize(): ?int
{
return ($this->_fn_getSize)();
}
public function tell(): int
{
return ($this->_fn_tell)();
}
public function eof(): bool
{
return ($this->_fn_eof)();
}
public function isSeekable(): bool
{
return ($this->_fn_isSeekable)();
}
public function rewind(): void
{
($this->_fn_rewind)();
}
public function seek($offset, $whence = SEEK_SET): void
{
($this->_fn_seek)($offset, $whence);
}
public function isWritable(): bool
{
return ($this->_fn_isWritable)();
}
public function write($string): int
{
return ($this->_fn_write)($string);
}
public function isReadable(): bool
{
return ($this->_fn_isReadable)();
}
public function read($length): string
{
return ($this->_fn_read)($length);
}
public function getContents(): string
{
return ($this->_fn_getContents)();
}
/**
* @return mixed
*/
public function getMetadata($key = null)
{
return ($this->_fn_getMetadata)($key);
}
}
Developer
To ensure a smooth integration process and optimal performance, follow these best practices: