--- /dev/null
+<?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) . ')';
+ }
+}
projects / yaffs-website / blobdiff