<?php
/**
* Flight: An extensible micro-framework.
*
* @copyright Copyright (c) 2011, Mike Cao <mike@mikecao.com>
* @license MIT, http://flightphp.com/license
*/
namespace flight;
use flight\core\Loader;
use flight\core\Dispatcher;
/**
* The Engine class contains the core functionality of the framework.
* It is responsible for loading an HTTP request, running the assigned services,
* and generating an HTTP response.
*
* Core methods
* @method void start() Starts engine
* @method void stop() Stops framework and outputs current response
* @method void halt(int $code = 200, string $message = '') Stops processing and returns a given response.
*
*
* Routing
* @method void route(string $pattern, callable $callback, bool $pass_route = false) Routes a URL to a callback function.
* @method \flight\net\Router router() Gets router
*
* Views
* @method void render(string $file, array $data = null, string $key = null) Renders template
* @method \flight\template\View view() Gets current view
*
* Request-response
* @method \flight\net\Request request() Gets current request
* @method \flight\net\Response response() Gets current response
* @method void error(\Exception $e) Sends an HTTP 500 response for any errors.
* @method void notFound() Sends an HTTP 404 response when a URL is not found.
* @method void redirect(string $url, int $code = 303) Redirects the current request to another URL.
* @method void json(mixed $data, int $code = 200, bool $encode = true, string $charset = 'utf-8', int $option = 0) Sends a JSON response.
* @method void jsonp(mixed $data, string $param = 'jsonp', int $code = 200, bool $encode = true, string $charset = 'utf-8', int $option = 0) Sends a JSONP response.
*
* HTTP caching
* @method void etag($id, string $type = 'strong') Handles ETag HTTP caching.
* @method void lastModified(int $time) Handles last modified HTTP caching.
*/
class Engine {
/**
* Stored variables.
*
* @var array
*/
protected $vars;
/**
* Class loader.
*
* @var Loader
*/
protected $loader;
/**
* Event dispatcher.
*
* @var Dispatcher
*/
protected $dispatcher;
/**
* Constructor.
*/
public function __construct() {
$this->vars = array();
$this->loader = new Loader();
$this->dispatcher = new Dispatcher();
$this->init();
}
/**
* Handles calls to class methods.
*
* @param string $name Method name
* @param array $params Method parameters
* @return mixed Callback results
* @throws \Exception
*/
public function __call($name, $params) {
$callback = $this->dispatcher->get($name);
if (is_callable($callback)) {
return $this->dispatcher->run($name, $params);
}
if (!$this->loader->get($name)) {
throw new \Exception("{$name} must be a mapped method.");
}
$shared = (!empty($params)) ? (bool)$params[0] : true;
return $this->loader->load($name, $shared);
}
/*** Core Methods ***/
/**
* Initializes the framework.
*/
public function init() {
static $initialized = false;
$self = $this;
if ($initialized) {
$this->vars = array();
$this->loader->reset();
$this->dispatcher->reset();
}
// Register default components
$this->loader->register('request', '\flight\net\Request');
$this->loader->register('response', '\flight\net\Response');
$this->loader->register('router', '\flight\net\Router');
$this->loader->register('view', '\flight\template\View', array(), function($view) use ($self) {
$view->path = $self->get('flight.views.path');
$view->extension = $self->get('flight.views.extension');
});
// Register framework methods
$methods = array(
'start','stop','route','halt','error','notFound',
'render','redirect','etag','lastModified','json','jsonp'
);
foreach ($methods as $name) {
$this->dispatcher->set($name, array($this, '_'.$name));
}
// Default configuration settings
$this->set('flight.base_url', null);
$this->set('flight.case_sensitive', false);
$this->set('flight.handle_errors', true);
$this->set('flight.log_errors', false);
$this->set('flight.views.path', './views');
$this->set('flight.views.extension', '.php');
$this->set('flight.content_length', true);
// Startup configuration
$this->before('start', function() use ($self) {
// Enable error handling
if ($self->get('flight.handle_errors')) {
set_error_handler(array($self, 'handleError'));
set_exception_handler(array($self, 'handleException'));
}
// Set case-sensitivity
$self->router()->case_sensitive = $self->get('flight.case_sensitive');
// Set Content-Length
$self->response()->content_length = $self->get('flight.content_length');
});
$initialized = true;
}
/**
* Custom error handler. Converts errors into exceptions.
*
* @param int $errno Error number
* @param int $errstr Error string
* @param int $errfile Error file name
* @param int $errline Error file line number
* @throws \ErrorException
*/
public function handleError($errno, $errstr, $errfile, $errline) {
if ($errno & error_reporting()) {
throw new \ErrorException($errstr, $errno, 0, $errfile, $errline);
}
}
/**
* Custom exception handler. Logs exceptions.
*
* @param \Exception $e Thrown exception
*/
public function handleException($e) {
if ($this->get('flight.log_errors')) {
error_log($e->getMessage());
}
$this->error($e);
}
/**
* Maps a callback to a framework method.
*
* @param string $name Method name
* @param callback $callback Callback function
* @throws \Exception If trying to map over a framework method
*/
public function map($name, $callback) {
if (method_exists($this, $name)) {
throw new \Exception('Cannot override an existing framework method.');
}
$this->dispatcher->set($name, $callback);
}
/**
* Registers a class to a framework method.
*
* @param string $name Method name
* @param string $class Class name
* @param array $params Class initialization parameters
* @param callback $callback Function to call after object instantiation
* @throws \Exception If trying to map over a framework method
*/
public function register($name, $class, array $params = array(), $callback = null) {
if (method_exists($this, $name)) {
throw new \Exception('Cannot override an existing framework method.');
}
$this->loader->register($name, $class, $params, $callback);
}
/**
* Adds a pre-filter to a method.
*
* @param string $name Method name
* @param callback $callback Callback function
*/
public function before($name, $callback) {
$this->dispatcher->hook($name, 'before', $callback);
}
/**
* Adds a post-filter to a method.
*
* @param string $name Method name
* @param callback $callback Callback function
*/
public function after($name, $callback) {
$this->dispatcher->hook($name, 'after', $callback);
}
/**
* Gets a variable.
*
* @param string $key Key
* @return mixed
*/
public function get($key = null) {
if ($key === null) return $this->vars;
return isset($this->vars[$key]) ? $this->vars[$key] : null;
}
/**
* Sets a variable.
*
* @param mixed $key Key
* @param string $value Value
*/
public function set($key, $value = null) {
if (is_array($key) || is_object($key)) {
foreach ($key as $k => $v) {
$this->vars[$k] = $v;
}
}
else {
$this->vars[$key] = $value;
}
}
/**
* Checks if a variable has been set.
*
* @param string $key Key
* @return bool Variable status
*/
public function has($key) {
return isset($this->vars[$key]);
}
/**
* Unsets a variable. If no key is passed in, clear all variables.
*
* @param string $key Key
*/
public function clear($key = null) {
if (is_null($key)) {
$this->vars = array();
}
else {
unset($this->vars[$key]);
}
}
/**
* Adds a path for class autoloading.
*
* @param string $dir Directory path
*/
public function path($dir) {
$this->loader->addDirectory($dir);
}
/*** Extensible Methods ***/
/**
* Starts the framework.
* @throws \Exception
*/
public function _start() {
$dispatched = false;
$self = $this;
$request = $this->request();
$response = $this->response();
$router = $this->router();
// Allow filters to run
$this->after('start', function() use ($self) {
$self->stop();
});
// Flush any existing output
if (ob_get_length() > 0) {
$response->write(ob_get_clean());
}
// Enable output buffering
ob_start();
// Route the request
while ($route = $router->route($request)) {
$params = array_values($route->params);
// Add route info to the parameter list
if ($route->pass) {
$params[] = $route;
}
// Call route handler
$continue = $this->dispatcher->execute(
$route->callback,
$params
);
$dispatched = true;
if (!$continue) break;
$router->next();
$dispatched = false;
}
if (!$dispatched) {
$this->notFound();
}
}
/**
* Stops the framework and outputs the current response.
*
* @param int $code HTTP status code
* @throws \Exception
*/
public function _stop($code = null) {
$response = $this->response();
if (!$response->sent()) {
if ($code !== null) {
$response->status($code);
}
$response->write(ob_get_clean());
$response->send();
}
}
/**
* Routes a URL to a callback function.
*
* @param string $pattern URL pattern to match
* @param callback $callback Callback function
* @param boolean $pass_route Pass the matching route object to the callback
*/
public function _route($pattern, $callback, $pass_route = false) {
$this->router()->map($pattern, $callback, $pass_route);
}
/**
* Stops processing and returns a given response.
*
* @param int $code HTTP status code
* @param string $message Response message
*/
public function _halt($code = 200, $message = '') {
$this->response()
->clear()
->status($code)
->write($message)
->send();
exit();
}
/**
* Sends an HTTP 500 response for any errors.
*
* @param \Exception|\Throwable $e Thrown exception
*/
public function _error($e) {
$msg = sprintf('<h1>500 Internal Server Error</h1>'.
'<h3>%s (%s)</h3>'.
'<pre>%s</pre>',
$e->getMessage(),
$e->getCode(),
$e->getTraceAsString()
);
try {
$this->response()
->clear()
->status(500)
->write($msg)
->send();
}
catch (\Throwable $t) { // PHP 7.0+
exit($msg);
} catch(\Exception $e) { // PHP < 7
exit($msg);
}
}
/**
* Sends an HTTP 404 response when a URL is not found.
*/
public function _notFound() {
$this->response()
->clear()
->status(404)
->write(
'<h1>404 Not Found</h1>'.
'<h3>The page you have requested could not be found.</h3>'.
str_repeat(' ', 512)
)
->send();
}
/**
* Redirects the current request to another URL.
*
* @param string $url URL
* @param int $code HTTP status code
*/
public function _redirect($url, $code = 303) {
$base = $this->get('flight.base_url');
if ($base === null) {
$base = $this->request()->base;
}
// Append base url to redirect url
if ($base != '/' && strpos($url, '://') === false) {
$url = $base . preg_replace('#/+#', '/', '/' . $url);
}
$this->response()
->clear()
->status($code)
->header('Location', $url)
->send();
}
/**
* Renders a template.
*
* @param string $file Template file
* @param array $data Template data
* @param string $key View variable name
* @throws \Exception
*/
public function _render($file, $data = null, $key = null) {
if ($key !== null) {
$this->view()->set($key, $this->view()->fetch($file, $data));
}
else {
$this->view()->render($file, $data);
}
}
/**
* Sends a JSON response.
*
* @param mixed $data JSON data
* @param int $code HTTP status code
* @param bool $encode Whether to perform JSON encoding
* @param string $charset Charset
* @param int $option Bitmask Json constant such as JSON_HEX_QUOT
* @throws \Exception
*/
public function _json(
$data,
$code = 200,
$encode = true,
$charset = 'utf-8',
$option = 0
) {
$json = ($encode) ? json_encode($data, $option) : $data;
$this->response()
->status($code)
->header('Content-Type', 'application/json; charset='.$charset)
->write($json)
->send();
}
/**
* Sends a JSONP response.
*
* @param mixed $data JSON data
* @param string $param Query parameter that specifies the callback name.
* @param int $code HTTP status code
* @param bool $encode Whether to perform JSON encoding
* @param string $charset Charset
* @param int $option Bitmask Json constant such as JSON_HEX_QUOT
* @throws \Exception
*/
public function _jsonp(
$data,
$param = 'jsonp',
$code = 200,
$encode = true,
$charset = 'utf-8',
$option = 0
) {
$json = ($encode) ? json_encode($data, $option) : $data;
$callback = $this->request()->query[$param];
$this->response()
->status($code)
->header('Content-Type', 'application/javascript; charset='.$charset)
->write($callback.'('.$json.');')
->send();
}
/**
* Handles ETag HTTP caching.
*
* @param string $id ETag identifier
* @param string $type ETag type
*/
public function _etag($id, $type = 'strong') {
$id = (($type === 'weak') ? 'W/' : '').$id;
$this->response()->header('ETag', $id);
if (isset($_SERVER['HTTP_IF_NONE_MATCH']) &&
$_SERVER['HTTP_IF_NONE_MATCH'] === $id) {
$this->halt(304);
}
}
/**
* Handles last modified HTTP caching.
*
* @param int $time Unix timestamp
*/
public function _lastModified($time) {
$this->response()->header('Last-Modified', gmdate('D, d M Y H:i:s \G\M\T', $time));
if (isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) &&
strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']) === $time) {
$this->halt(304);
}
}
}