274 lines
		
	
	
		
			7.4 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
			
		
		
	
	
			274 lines
		
	
	
		
			7.4 KiB
		
	
	
	
		
			PHP
		
	
	
	
	
	
<?php
 | 
						|
namespace GuzzleHttp;
 | 
						|
 | 
						|
use Psr\Http\Message\RequestInterface;
 | 
						|
 | 
						|
/**
 | 
						|
 * Creates a composed Guzzle handler function by stacking middlewares on top of
 | 
						|
 * an HTTP handler function.
 | 
						|
 */
 | 
						|
class HandlerStack
 | 
						|
{
 | 
						|
    /** @var callable */
 | 
						|
    private $handler;
 | 
						|
 | 
						|
    /** @var array */
 | 
						|
    private $stack = [];
 | 
						|
 | 
						|
    /** @var callable|null */
 | 
						|
    private $cached;
 | 
						|
 | 
						|
    /**
 | 
						|
     * Creates a default handler stack that can be used by clients.
 | 
						|
     *
 | 
						|
     * The returned handler will wrap the provided handler or use the most
 | 
						|
     * appropriate default handler for you system. The returned HandlerStack has
 | 
						|
     * support for cookies, redirects, HTTP error exceptions, and preparing a body
 | 
						|
     * before sending.
 | 
						|
     *
 | 
						|
     * The returned handler stack can be passed to a client in the "handler"
 | 
						|
     * option.
 | 
						|
     *
 | 
						|
     * @param callable $handler HTTP handler function to use with the stack. If no
 | 
						|
     *                          handler is provided, the best handler for your
 | 
						|
     *                          system will be utilized.
 | 
						|
     *
 | 
						|
     * @return HandlerStack
 | 
						|
     */
 | 
						|
    public static function create(callable $handler = null)
 | 
						|
    {
 | 
						|
        $stack = new self($handler ?: choose_handler());
 | 
						|
        $stack->push(Middleware::httpErrors(), 'http_errors');
 | 
						|
        $stack->push(Middleware::redirect(), 'allow_redirects');
 | 
						|
        $stack->push(Middleware::cookies(), 'cookies');
 | 
						|
        $stack->push(Middleware::prepareBody(), 'prepare_body');
 | 
						|
 | 
						|
        return $stack;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * @param callable $handler Underlying HTTP handler.
 | 
						|
     */
 | 
						|
    public function __construct(callable $handler = null)
 | 
						|
    {
 | 
						|
        $this->handler = $handler;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Invokes the handler stack as a composed handler
 | 
						|
     *
 | 
						|
     * @param RequestInterface $request
 | 
						|
     * @param array            $options
 | 
						|
     */
 | 
						|
    public function __invoke(RequestInterface $request, array $options)
 | 
						|
    {
 | 
						|
        $handler = $this->resolve();
 | 
						|
 | 
						|
        return $handler($request, $options);
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Dumps a string representation of the stack.
 | 
						|
     *
 | 
						|
     * @return string
 | 
						|
     */
 | 
						|
    public function __toString()
 | 
						|
    {
 | 
						|
        $depth = 0;
 | 
						|
        $stack = [];
 | 
						|
        if ($this->handler) {
 | 
						|
            $stack[] = "0) Handler: " . $this->debugCallable($this->handler);
 | 
						|
        }
 | 
						|
 | 
						|
        $result = '';
 | 
						|
        foreach (array_reverse($this->stack) as $tuple) {
 | 
						|
            $depth++;
 | 
						|
            $str = "{$depth}) Name: '{$tuple[1]}', ";
 | 
						|
            $str .= "Function: " . $this->debugCallable($tuple[0]);
 | 
						|
            $result = "> {$str}\n{$result}";
 | 
						|
            $stack[] = $str;
 | 
						|
        }
 | 
						|
 | 
						|
        foreach (array_keys($stack) as $k) {
 | 
						|
            $result .= "< {$stack[$k]}\n";
 | 
						|
        }
 | 
						|
 | 
						|
        return $result;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Set the HTTP handler that actually returns a promise.
 | 
						|
     *
 | 
						|
     * @param callable $handler Accepts a request and array of options and
 | 
						|
     *                          returns a Promise.
 | 
						|
     */
 | 
						|
    public function setHandler(callable $handler)
 | 
						|
    {
 | 
						|
        $this->handler = $handler;
 | 
						|
        $this->cached = null;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Returns true if the builder has a handler.
 | 
						|
     *
 | 
						|
     * @return bool
 | 
						|
     */
 | 
						|
    public function hasHandler()
 | 
						|
    {
 | 
						|
        return (bool) $this->handler;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Unshift a middleware to the bottom of the stack.
 | 
						|
     *
 | 
						|
     * @param callable $middleware Middleware function
 | 
						|
     * @param string   $name       Name to register for this middleware.
 | 
						|
     */
 | 
						|
    public function unshift(callable $middleware, $name = null)
 | 
						|
    {
 | 
						|
        array_unshift($this->stack, [$middleware, $name]);
 | 
						|
        $this->cached = null;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Push a middleware to the top of the stack.
 | 
						|
     *
 | 
						|
     * @param callable $middleware Middleware function
 | 
						|
     * @param string   $name       Name to register for this middleware.
 | 
						|
     */
 | 
						|
    public function push(callable $middleware, $name = '')
 | 
						|
    {
 | 
						|
        $this->stack[] = [$middleware, $name];
 | 
						|
        $this->cached = null;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Add a middleware before another middleware by name.
 | 
						|
     *
 | 
						|
     * @param string   $findName   Middleware to find
 | 
						|
     * @param callable $middleware Middleware function
 | 
						|
     * @param string   $withName   Name to register for this middleware.
 | 
						|
     */
 | 
						|
    public function before($findName, callable $middleware, $withName = '')
 | 
						|
    {
 | 
						|
        $this->splice($findName, $withName, $middleware, true);
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Add a middleware after another middleware by name.
 | 
						|
     *
 | 
						|
     * @param string   $findName   Middleware to find
 | 
						|
     * @param callable $middleware Middleware function
 | 
						|
     * @param string   $withName   Name to register for this middleware.
 | 
						|
     */
 | 
						|
    public function after($findName, callable $middleware, $withName = '')
 | 
						|
    {
 | 
						|
        $this->splice($findName, $withName, $middleware, false);
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Remove a middleware by instance or name from the stack.
 | 
						|
     *
 | 
						|
     * @param callable|string $remove Middleware to remove by instance or name.
 | 
						|
     */
 | 
						|
    public function remove($remove)
 | 
						|
    {
 | 
						|
        $this->cached = null;
 | 
						|
        $idx = is_callable($remove) ? 0 : 1;
 | 
						|
        $this->stack = array_values(array_filter(
 | 
						|
            $this->stack,
 | 
						|
            function ($tuple) use ($idx, $remove) {
 | 
						|
                return $tuple[$idx] !== $remove;
 | 
						|
            }
 | 
						|
        ));
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Compose the middleware and handler into a single callable function.
 | 
						|
     *
 | 
						|
     * @return callable
 | 
						|
     */
 | 
						|
    public function resolve()
 | 
						|
    {
 | 
						|
        if (!$this->cached) {
 | 
						|
            if (!($prev = $this->handler)) {
 | 
						|
                throw new \LogicException('No handler has been specified');
 | 
						|
            }
 | 
						|
 | 
						|
            foreach (array_reverse($this->stack) as $fn) {
 | 
						|
                $prev = $fn[0]($prev);
 | 
						|
            }
 | 
						|
 | 
						|
            $this->cached = $prev;
 | 
						|
        }
 | 
						|
 | 
						|
        return $this->cached;
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * @param $name
 | 
						|
     * @return int
 | 
						|
     */
 | 
						|
    private function findByName($name)
 | 
						|
    {
 | 
						|
        foreach ($this->stack as $k => $v) {
 | 
						|
            if ($v[1] === $name) {
 | 
						|
                return $k;
 | 
						|
            }
 | 
						|
        }
 | 
						|
 | 
						|
        throw new \InvalidArgumentException("Middleware not found: $name");
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Splices a function into the middleware list at a specific position.
 | 
						|
     *
 | 
						|
     * @param          $findName
 | 
						|
     * @param          $withName
 | 
						|
     * @param callable $middleware
 | 
						|
     * @param          $before
 | 
						|
     */
 | 
						|
    private function splice($findName, $withName, callable $middleware, $before)
 | 
						|
    {
 | 
						|
        $this->cached = null;
 | 
						|
        $idx = $this->findByName($findName);
 | 
						|
        $tuple = [$middleware, $withName];
 | 
						|
 | 
						|
        if ($before) {
 | 
						|
            if ($idx === 0) {
 | 
						|
                array_unshift($this->stack, $tuple);
 | 
						|
            } else {
 | 
						|
                $replacement = [$tuple, $this->stack[$idx]];
 | 
						|
                array_splice($this->stack, $idx, 1, $replacement);
 | 
						|
            }
 | 
						|
        } elseif ($idx === count($this->stack) - 1) {
 | 
						|
            $this->stack[] = $tuple;
 | 
						|
        } else {
 | 
						|
            $replacement = [$this->stack[$idx], $tuple];
 | 
						|
            array_splice($this->stack, $idx, 1, $replacement);
 | 
						|
        }
 | 
						|
    }
 | 
						|
 | 
						|
    /**
 | 
						|
     * Provides a debug string for a given callable.
 | 
						|
     *
 | 
						|
     * @param array|callable $fn Function to write as a string.
 | 
						|
     *
 | 
						|
     * @return string
 | 
						|
     */
 | 
						|
    private function debugCallable($fn)
 | 
						|
    {
 | 
						|
        if (is_string($fn)) {
 | 
						|
            return "callable({$fn})";
 | 
						|
        }
 | 
						|
 | 
						|
        if (is_array($fn)) {
 | 
						|
            return is_string($fn[0])
 | 
						|
                ? "callable({$fn[0]}::{$fn[1]})"
 | 
						|
                : "callable(['" . get_class($fn[0]) . "', '{$fn[1]}'])";
 | 
						|
        }
 | 
						|
 | 
						|
        return 'callable(' . spl_object_hash($fn) . ')';
 | 
						|
    }
 | 
						|
}
 |