Begin work on custom code plugins support.

.gitignore

@@ -32,3 +32,8 @@ web/static/yarn-error\.log
 # Docker files
 /docker-compose.yml
 /*.tar.gz
+
+# Plugins
+/plugins/*
+/plugins/**/*
+!/plugins/.gitkeep

bootstrap/app.php

@@ -58,6 +58,10 @@ ini_set('session.use_strict_mode',      1);
 $autoloader = require(APP_INCLUDE_VENDOR . '/autoload.php');
 $autoloader->setPsr4('Proxy\\', APP_INCLUDE_TEMP . '/proxies');
 
+// Initialize plugins
+$plugins = new \App\Plugins(APP_INCLUDE_ROOT.'/plugins');
+$plugins->registerAutoloaders($autoloader);
+
 // Set up DI container.
 $di = new \Slim\Container([
     'settings' => [
@@ -69,8 +73,12 @@ $di = new \Slim\Container([
     ]
 ]);
 
+$di[\App\Plugins::class] = $plugins;
+
 // Define services.
 $settings = require(dirname(__DIR__).'/config/settings.php');
 call_user_func(include(dirname(__DIR__).'/config/services.php'), $di, $settings);
 
+$plugins->registerServices($di, $settings);
+
 return $di;

composer.json

@@ -41,6 +41,7 @@
         "php-http/guzzle6-adapter": "^1.1",
         "slim/slim": "^3.0",
         "supervisorphp/supervisor": "^3.0",
+        "symfony/event-dispatcher": "^4.1",
         "symfony/finder": "^4.1",
         "zendframework/zend-config": "^3.1.0",
         "zendframework/zend-paginator": "^2.7"

composer.lock

@@ -4,7 +4,7 @@
         "Read more about it at https://getcomposer.org/doc/01-basic-usage.md#installing-dependencies",
         "This file is @generated automatically"
     ],
-    "content-hash": "594ac3f2423a143d5621fb2cffbd11fa",
+    "content-hash": "1d77d7c553cb7dd8c3f52c09642fcf36",
     "packages": [
         {
             "name": "azuracast/azuraforms",
@@ -3419,6 +3419,69 @@
             "homepage": "https://symfony.com",
             "time": "2018-07-26T11:24:31+00:00"
         },
+        {
+            "name": "symfony/event-dispatcher",
+            "version": "v4.1.4",
+            "source": {
+                "type": "git",
+                "url": "https://github.com/symfony/event-dispatcher.git",
+                "reference": "bfb30c2ad377615a463ebbc875eba64a99f6aa3e"
+            },
+            "dist": {
+                "type": "zip",
+                "url": "https://api.github.com/repos/symfony/event-dispatcher/zipball/bfb30c2ad377615a463ebbc875eba64a99f6aa3e",
+                "reference": "bfb30c2ad377615a463ebbc875eba64a99f6aa3e",
+                "shasum": ""
+            },
+            "require": {
+                "php": "^7.1.3"
+            },
+            "conflict": {
+                "symfony/dependency-injection": "<3.4"
+            },
+            "require-dev": {
+                "psr/log": "~1.0",
+                "symfony/config": "~3.4|~4.0",
+                "symfony/dependency-injection": "~3.4|~4.0",
+                "symfony/expression-language": "~3.4|~4.0",
+                "symfony/stopwatch": "~3.4|~4.0"
+            },
+            "suggest": {
+                "symfony/dependency-injection": "",
+                "symfony/http-kernel": ""
+            },
+            "type": "library",
+            "extra": {
+                "branch-alias": {
+                    "dev-master": "4.1-dev"
+                }
+            },
+            "autoload": {
+                "psr-4": {
+                    "Symfony\\Component\\EventDispatcher\\": ""
+                },
+                "exclude-from-classmap": [
+                    "/Tests/"
+                ]
+            },
+            "notification-url": "https://packagist.org/downloads/",
+            "license": [
+                "MIT"
+            ],
+            "authors": [
+                {
+                    "name": "Fabien Potencier",
+                    "email": "fabien@symfony.com"
+                },
+                {
+                    "name": "Symfony Community",
+                    "homepage": "https://symfony.com/contributors"
+                }
+            ],
+            "description": "Symfony EventDispatcher Component",
+            "homepage": "https://symfony.com",
+            "time": "2018-07-26T09:10:45+00:00"
+        },
         {
             "name": "symfony/finder",
             "version": "v4.1.4",
@@ -5956,69 +6019,6 @@
             "homepage": "https://symfony.com",
             "time": "2018-07-26T11:00:49+00:00"
         },
-        {
-            "name": "symfony/event-dispatcher",
-            "version": "v4.1.4",
-            "source": {
-                "type": "git",
-                "url": "https://github.com/symfony/event-dispatcher.git",
-                "reference": "bfb30c2ad377615a463ebbc875eba64a99f6aa3e"
-            },
-            "dist": {
-                "type": "zip",
-                "url": "https://api.github.com/repos/symfony/event-dispatcher/zipball/bfb30c2ad377615a463ebbc875eba64a99f6aa3e",
-                "reference": "bfb30c2ad377615a463ebbc875eba64a99f6aa3e",
-                "shasum": ""
-            },
-            "require": {
-                "php": "^7.1.3"
-            },
-            "conflict": {
-                "symfony/dependency-injection": "<3.4"
-            },
-            "require-dev": {
-                "psr/log": "~1.0",
-                "symfony/config": "~3.4|~4.0",
-                "symfony/dependency-injection": "~3.4|~4.0",
-                "symfony/expression-language": "~3.4|~4.0",
-                "symfony/stopwatch": "~3.4|~4.0"
-            },
-            "suggest": {
-                "symfony/dependency-injection": "",
-                "symfony/http-kernel": ""
-            },
-            "type": "library",
-            "extra": {
-                "branch-alias": {
-                    "dev-master": "4.1-dev"
-                }
-            },
-            "autoload": {
-                "psr-4": {
-                    "Symfony\\Component\\EventDispatcher\\": ""
-                },
-                "exclude-from-classmap": [
-                    "/Tests/"
-                ]
-            },
-            "notification-url": "https://packagist.org/downloads/",
-            "license": [
-                "MIT"
-            ],
-            "authors": [
-                {
-                    "name": "Fabien Potencier",
-                    "email": "fabien@symfony.com"
-                },
-                {
-                    "name": "Symfony Community",
-                    "homepage": "https://symfony.com/contributors"
-                }
-            ],
-            "description": "Symfony EventDispatcher Component",
-            "homepage": "https://symfony.com",
-            "time": "2018-07-26T09:10:45+00:00"
-        },
         {
             "name": "symfony/polyfill-ctype",
             "version": "v1.9.0",

config/events.php

@@ -0,0 +1,14 @@
+<?php
+return function (\Symfony\Component\EventDispatcher\EventDispatcher $dispatcher, \Slim\Container $di, $settings) {
+
+    $dispatcher->addSubscriber(new \App\EventHandler\DefaultRoutes(__DIR__.'/routes.php'));
+    $dispatcher->addSubscriber(new \App\EventHandler\DefaultView($di));
+    $dispatcher->addSubscriber(new \App\EventHandler\DefaultNowPlaying());
+
+    $dispatcher->addListener(\App\Event\SendWebhooks::NAME, function(\App\Event\SendWebhooks $event) use ($di) {
+        /** @var \App\Webhook\Dispatcher $webhook_dispatcher */
+        $webhook_dispatcher = $di[\App\Webhook\Dispatcher::class];
+
+        $webhook_dispatcher->dispatch($event);
+    });
+};

config/services.php

@@ -233,46 +233,9 @@ return function (\Slim\Container $di, $settings) {
         $view = new App\View(dirname(__DIR__) . '/resources/templates');
         $view->setFileExtension('phtml');
 
-        $view->registerFunction('service', function($service) use ($di) {
+        /** @var \Symfony\Component\EventDispatcher\EventDispatcher $dispatcher */
-            return $di->get($service);
+        $dispatcher = $di[\Symfony\Component\EventDispatcher\EventDispatcher::class];
-        });
+        $dispatcher->dispatch(\App\Event\BuildView::NAME, new \App\Event\BuildView($view));
-
-        $view->registerFunction('escapeJs', function($string) {
-            return json_encode($string);
-        });
-
-        $view->registerFunction('mailto', function ($address, $link_text = null) {
-            $address = substr(chunk_split(bin2hex(" $address"), 2, ";&#x"), 3, -3);
-            $link_text = $link_text ?? $address;
-
-            return '<a href="mailto:' . $address . '">' . $link_text . '</a>';
-        });
-
-        $view->registerFunction('pluralize', function ($word, $num = 0) {
-            if ((int)$num === 1) {
-                return $word;
-            } else {
-                return \Doctrine\Common\Inflector\Inflector::pluralize($word);
-            }
-        });
-
-        $view->registerFunction('truncate', function ($text, $length = 80) {
-            return \App\Utilities::truncate_text($text, $length);
-        });
-
-        /** @var \App\Session $session */
-        $session = $di[\App\Session::class];
-
-        $view->addData([
-            'app_settings' => $di['app_settings'],
-            'router' => $di['router'],
-            'request' => $di['request'],
-            'assets' => $di[\App\Assets::class],
-            'auth' => $di[\App\Auth::class],
-            'acl' => $di[\App\Acl::class],
-            'flash' => $session->getFlash(),
-            'customization' => $di[\App\Customization::class],
-        ]);
 
         return $view;
     });
@@ -337,6 +300,21 @@ return function (\Slim\Container $di, $settings) {
         ]);
     };
 
+    $di[\Symfony\Component\EventDispatcher\EventDispatcher::class] = function($di) use ($settings) {
+        $dispatcher = new \Symfony\Component\EventDispatcher\EventDispatcher();
+
+        // Register application default events.
+        call_user_func(include(__DIR__.'/events.php'), $dispatcher, $di, $settings);
+
+        /** @var \App\Plugins $plugins */
+        $plugins = $di[\App\Plugins::class];
+
+        // Register plugin-provided events.
+        $plugins->registerEvents($dispatcher, $di, $settings);
+
+        return $dispatcher;
+    };
+
     //
     // AzuraCast-specific dependencies
     //
@@ -401,23 +379,9 @@ return function (\Slim\Container $di, $settings) {
 
         $app = new \Slim\App($di);
 
-        // Get the current user entity object and assign it into the request if it exists.
+        /** @var \Symfony\Component\EventDispatcher\EventDispatcher $dispatcher */
-        $app->add(\App\Middleware\GetCurrentUser::class);
+        $dispatcher = $di[\Symfony\Component\EventDispatcher\EventDispatcher::class];
-
+        $dispatcher->dispatch(\App\Event\BuildRoutes::NAME, new \App\Event\BuildRoutes($app));
-        // Inject the application router into the request object.
-        $app->add(\App\Middleware\EnableRouter::class);
-
-        // Inject the session manager into the request object.
-        $app->add(\App\Middleware\EnableSession::class);
-
-        // Check HTTPS setting and enforce Content Security Policy accordingly.
-        $app->add(\App\Middleware\EnforceSecurity::class);
-
-        // Remove trailing slash from all URLs when routing.
-        $app->add(\App\Middleware\RemoveSlashes::class);
-
-        // Load routes
-        call_user_func(include(__DIR__.'/routes.php'), $app);
 
         return $app;
     };

src/Event/BuildRoutes.php

@@ -0,0 +1,22 @@
+<?php
+namespace App\Event;
+
+use Slim\App;
+use Symfony\Component\EventDispatcher\Event;
+
+class BuildRoutes extends Event
+{
+    const NAME = 'build-routes';
+
+    protected $app;
+
+    public function __construct(App $app)
+    {
+        $this->app = $app;
+    }
+
+    public function getApp(): App
+    {
+        return $this->app;
+    }
+}

src/Event/BuildView.php

@@ -0,0 +1,22 @@
+<?php
+namespace App\Event;
+
+use App\View;
+use Symfony\Component\EventDispatcher\Event;
+
+class BuildView extends Event
+{
+    const NAME = 'build-view';
+
+    protected $view;
+
+    public function __construct(View $view)
+    {
+        $this->view = $view;
+    }
+
+    public function getView(): View
+    {
+        return $this->view;
+    }
+}

src/Event/GenerateRawNowPlaying.php

@@ -0,0 +1,82 @@
+<?php
+namespace App\Event;
+
+use App\Entity\Station;
+use App\Radio\Frontend\FrontendAbstract;
+use App\Radio\Remote\RemoteAbstract;
+use Symfony\Component\EventDispatcher\Event;
+
+class GenerateRawNowPlaying extends Event
+{
+    const NAME = 'nowplaying-generate-raw';
+
+    /** @var Station */
+    protected $station;
+
+    /** @var FrontendAbstract */
+    protected $frontend;
+
+    /** @var RemoteAbstract[] */
+    protected $remotes;
+
+    /** @var bool */
+    protected $include_clients = false;
+
+    /** @var string|null The preloaded "payload" to supply to the nowplaying adapters, if one is available. */
+    protected $payload;
+
+    /** @var array The composed "raw" NowPlaying data. */
+    protected $np_raw = [];
+
+    public function __construct(
+        Station $station,
+        FrontendAbstract $frontend,
+        array $remotes,
+        $payload = null,
+        $include_clients = false
+    ) {
+        $this->station = $station;
+        $this->frontend = $frontend;
+        $this->remotes = $remotes;
+        $this->payload = $payload;
+        $this->include_clients = $include_clients;
+    }
+
+    public function getStation(): Station
+    {
+        return $this->station;
+    }
+
+    public function getFrontend(): FrontendAbstract
+    {
+        return $this->frontend;
+    }
+
+    /**
+     * @return RemoteAbstract[]
+     */
+    public function getRemotes(): array
+    {
+        return $this->remotes;
+    }
+
+    public function includeClients(): bool
+    {
+        return $this->include_clients;
+    }
+
+    public function getPayload(): ?string
+    {
+        return $this->payload;
+    }
+
+    public function getRawResponse(): array
+    {
+        return $this->np_raw;
+    }
+
+    public function setRawResponse(array $np): void
+    {
+        $this->np_raw = $np;
+    }
+}

src/Event/SendWebhooks.php

@@ -0,0 +1,93 @@
+<?php
+namespace App\Event;
+
+use App\Entity\Api\NowPlaying;
+use App\Entity\Station;
+use Symfony\Component\EventDispatcher\Event;
+
+class SendWebhooks extends Event
+{
+    const NAME = 'webhooks-send';
+
+    /** @var Station */
+    protected $station;
+
+    /** @var NowPlaying */
+    protected $np;
+
+    /** @var array */
+    protected $triggers = [];
+
+    /** @var bool */
+    protected $is_standalone = true;
+
+    public function __construct(Station $station, NowPlaying $np, $np_old = null, $is_standalone = true)
+    {
+        $this->station = $station;
+        $this->np = $np;
+        $this->is_standalone = $is_standalone;
+
+        $to_trigger = ['all'];
+
+        if ($np_old instanceof NowPlaying) {
+            if ($np_old->now_playing->song->id !== $np->now_playing->song->id) {
+                $to_trigger[] = 'song_changed';
+            }
+
+            if ($np_old->listeners->current > $np->listeners->current) {
+                $to_trigger[] = 'listener_lost';
+            } elseif ($np_old->listeners->current < $np->listeners->current) {
+                $to_trigger[] = 'listener_gained';
+            }
+
+            if ($np_old->live->is_live === false && $np->live->is_live === true) {
+                $to_trigger[] = 'live_connect';
+            } elseif ($np_old->live->is_live === true && $np->live->is_live === false) {
+                $to_trigger[] = 'live_disconnect';
+            }
+        }
+
+        $this->triggers = $to_trigger;
+    }
+
+    /**
+     * @return Station
+     */
+    public function getStation(): Station
+    {
+        return $this->station;
+    }
+
+    /**
+     * @return NowPlaying
+     */
+    public function getNowPlaying(): NowPlaying
+    {
+        return $this->np;
+    }
+
+    /**
+     * @return array
+     */
+    public function getTriggers(): array
+    {
+        return $this->triggers;
+    }
+
+    /**
+     * @param $trigger_name
+     * @return bool
+     */
+    public function hasTrigger($trigger_name): bool
+    {
+        return in_array($trigger_name, $this->triggers);
+    }
+
+    /**
+     * @return bool
+     */
+    public function isStandalone(): bool
+    {
+        return $this->is_standalone;
+    }
+}

src/EventHandler/DefaultNowPlaying.php

@@ -0,0 +1,55 @@
+<?php
+namespace App\EventHandler;
+
+use App\Event\GenerateRawNowPlaying;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+
+class DefaultNowPlaying implements EventSubscriberInterface
+{
+    public static function getSubscribedEvents()
+    {
+        if (APP_TESTING_MODE) {
+            return [];
+        }
+
+        return [
+            GenerateRawNowPlaying::NAME => [
+                ['loadRawFromFrontend', 10],
+                ['addToRawFromRemotes', 0],
+                ['cleanUpRawOutput', -10],
+            ],
+        ];
+    }
+
+    public function loadRawFromFrontend(GenerateRawNowPlaying $event)
+    {
+        $np_raw = $event->getFrontend()->getNowPlaying($event->getPayload(), $event->includeClients());
+
+        $event->setRawResponse($np_raw);
+    }
+
+    public function addToRawFromRemotes(GenerateRawNowPlaying $event)
+    {
+        $np_raw = $event->getRawResponse();
+
+        // Loop through all remotes and update NP data accordingly.
+        foreach($event->getRemotes() as $remote_adapter) {
+            $remote_adapter->updateNowPlaying($np_raw, $event->includeClients());
+        }
+
+        $event->setRawResponse($np_raw);
+    }
+
+    public function cleanUpRawOutput(GenerateRawNowPlaying $event)
+    {
+        $np_raw = $event->getRawResponse();
+
+        array_walk($np_raw['current_song'], function(&$value) {
+            $value = htmlspecialchars_decode($value);
+            $value = trim($value);
+        });
+
+        $event->setRawResponse($np_raw);
+    }
+
+}

src/EventHandler/DefaultRoutes.php

@@ -0,0 +1,50 @@
+<?php
+namespace App\EventHandler;
+
+use App\Event\BuildRoutes;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+
+class DefaultRoutes implements EventSubscriberInterface
+{
+    public static function getSubscribedEvents()
+    {
+        return [
+            BuildRoutes::NAME => [
+                ['addDefaultMiddleware', 1],
+                ['addDefaultRoutes', 0],
+            ],
+        ];
+    }
+
+    protected $routes_path;
+
+    public function __construct($routes_path)
+    {
+        $this->routes_path = $routes_path;
+    }
+
+    public function addDefaultMiddleware(BuildRoutes $event)
+    {
+        $app = $event->getApp();
+
+        // Get the current user entity object and assign it into the request if it exists.
+        $app->add(\App\Middleware\GetCurrentUser::class);
+
+        // Inject the application router into the request object.
+        $app->add(\App\Middleware\EnableRouter::class);
+
+        // Inject the session manager into the request object.
+        $app->add(\App\Middleware\EnableSession::class);
+
+        // Check HTTPS setting and enforce Content Security Policy accordingly.
+        $app->add(\App\Middleware\EnforceSecurity::class);
+
+        // Remove trailing slash from all URLs when routing.
+        $app->add(\App\Middleware\RemoveSlashes::class);
+    }
+
+    public function addDefaultRoutes(BuildRoutes $event)
+    {
+        call_user_func(include($this->routes_path), $event->getApp());
+    }
+}

src/EventHandler/DefaultView.php

@@ -0,0 +1,76 @@
+<?php
+namespace App\EventHandler;
+
+use App\Event\BuildView;
+use Slim\Container;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+
+class DefaultView implements EventSubscriberInterface
+{
+    public static function getSubscribedEvents()
+    {
+        return [
+            BuildView::NAME => [
+                ['addViewFunctions', 1],
+                ['addViewData', 0],
+            ],
+        ];
+    }
+
+    /** @var Container */
+    protected $di;
+
+    public function __construct(Container $di)
+    {
+        $this->di = $di;
+    }
+
+    public function addViewFunctions(BuildView $event)
+    {
+        $view = $event->getView();
+
+        $view->registerFunction('service', function($service) {
+            return $this->di->get($service);
+        });
+
+        $view->registerFunction('escapeJs', function($string) {
+            return json_encode($string);
+        });
+
+        $view->registerFunction('mailto', function ($address, $link_text = null) {
+            $address = substr(chunk_split(bin2hex(" $address"), 2, ";&#x"), 3, -3);
+            $link_text = $link_text ?? $address;
+
+            return '<a href="mailto:' . $address . '">' . $link_text . '</a>';
+        });
+
+        $view->registerFunction('pluralize', function ($word, $num = 0) {
+            if ((int)$num === 1) {
+                return $word;
+            } else {
+                return \Doctrine\Common\Inflector\Inflector::pluralize($word);
+            }
+        });
+
+        $view->registerFunction('truncate', function ($text, $length = 80) {
+            return \App\Utilities::truncate_text($text, $length);
+        });
+    }
+
+    public function addViewData(BuildView $event)
+    {
+        /** @var \App\Session $session */
+        $session = $this->di[\App\Session::class];
+
+        $event->getView()->addData([
+            'app_settings' => $this->di['app_settings'],
+            'router' => $this->di['router'],
+            'request' => $this->di['request'],
+            'assets' => $this->di[\App\Assets::class],
+            'auth' => $this->di[\App\Auth::class],
+            'acl' => $this->di[\App\Acl::class],
+            'flash' => $session->getFlash(),
+            'customization' => $this->di[\App\Customization::class],
+        ]);
+    }
+}

src/EventHandler/DefaultWebhooks.php

@@ -0,0 +1,137 @@
+<?php
+namespace App\EventHandler;
+
+use App\Entity;
+use App\Event\SendWebhooks;
+use App\Exception;
+use App\Webhook\Connector;
+use Monolog\Handler\TestHandler;
+use Monolog\Logger;
+use Pimple\Psr11\ServiceLocator;
+use Symfony\Component\EventDispatcher\EventSubscriberInterface;
+
+class DefaultWebhooks implements EventSubscriberInterface
+{
+    /** @var Logger */
+    protected $logger;
+
+    /** @var ServiceLocator */
+    protected $connectors;
+
+    public function __construct(Logger $logger, ServiceLocator $connectors)
+    {
+        $this->logger = $logger;
+        $this->connectors = $connectors;
+    }
+
+    public static function getSubscribedEvents()
+    {
+        if (APP_TESTING_MODE) {
+            return [];
+        }
+
+        return [
+            SendWebhooks::NAME => [
+                ['dispatchWebhooks', 0],
+            ],
+        ];
+    }
+
+    public function dispatchWebhooks(SendWebhooks $event)
+    {
+        // Compile list of connectors for the station. Always dispatch to the local websocket receiver.
+        $connectors = [];
+
+        if ($event->isStandalone()) {
+            $connectors[] = [
+                'type' => 'local',
+                'triggers' => [],
+                'config' => [],
+            ];
+        }
+
+        // Assemble list of webhooks for the station
+        $station_webhooks = $event->getStation()->getWebhooks();
+
+        if ($station_webhooks->count() > 0) {
+            foreach($station_webhooks as $webhook) {
+                /** @var Entity\StationWebhook $webhook */
+                if ($webhook->isEnabled()) {
+                    $connectors[] = [
+                        'type' => $webhook->getType(),
+                        'triggers' => $webhook->getTriggers() ?: [],
+                        'config' => $webhook->getConfig() ?: [],
+                    ];
+                }
+            }
+        }
+
+        $this->logger->debug('Triggering events: '.implode(', ', $event->getTriggers()));
+
+        // Trigger all appropriate webhooks.
+        foreach($connectors as $connector) {
+            if (!$this->connectors->has($connector['type'])) {
+                $this->logger->error(sprintf('Webhook connector "%s" does not exist; skipping.', $connector['type']));
+                continue;
+            }
+
+            /** @var Connector\ConnectorInterface $connector_obj */
+            $connector_obj = $this->connectors->get($connector['type']);
+
+            if ($connector_obj->shouldDispatch($event, (array)$connector['triggers'])) {
+                $this->logger->debug(sprintf('Dispatching connector "%s".', $connector['type']));
+
+                $connector_obj->dispatch($event, (array)$connector['config']);
+            }
+        }
+    }
+
+    /**
+     * Send a "test" dispatch of the web hook, regardless of whether it is currently enabled, and
+     * return any logging information this yields.
+     *
+     * @param Entity\Station $station
+     * @param Entity\StationWebhook $webhook
+     * @return TestHandler
+     * @throws Exception
+     */
+    public function testDispatch(Entity\Station $station, Entity\StationWebhook $webhook)
+    {
+        $webhook_type = $webhook->getType();
+        $webhook_config = $webhook->getConfig();
+
+        if (!$this->connectors->has($webhook_type)) {
+            throw new Exception(sprintf('Webhook connector "%s" does not exist; skipping.', $webhook_type));
+        }
+
+        $handler = new TestHandler(Logger::DEBUG, false);
+        $this->logger->pushHandler($handler);
+
+        /** @var Connector\ConnectorInterface $connector_obj */
+        $connector_obj = $this->connectors->get($webhook_type);
+
+        $np = $station->getNowplaying();
+
+        $event = new SendWebhooks($station, $np);
+        $connector_obj->dispatch($event, $webhook_config);
+
+        $this->logger->popHandler();
+
+        return $handler;
+    }
+
+    /**
+     * Directly access a webhook connector of the specified type.
+     *
+     * @param $type
+     * @return Connector\ConnectorInterface
+     */
+    public function getConnector($type): Connector\ConnectorInterface
+    {
+        if ($this->connectors->has($type)) {
+            return $this->connectors->get($type);
+        }
+
+        throw new \InvalidArgumentException('Invalid web hook connector type specified.');
+    }
+}

src/Middleware/EnableView.php

@@ -28,7 +28,6 @@ class EnableView
     {
         $this->view->addData([
             'request' => $request,
-            'user' => $request->getAttribute(Request::ATTRIBUTE_USER),
         ]);
 
         $request = $request->withAttribute(Request::ATTRIBUTE_VIEW, $this->view);

src/Middleware/GetCurrentUser.php

@@ -3,9 +3,11 @@ namespace App\Middleware;
 
 use App\Auth;
 use App\Customization;
+use App\Event\BuildView;
 use App\Http\Request;
 use App\Http\Response;
 use App\Entity;
+use Symfony\Component\EventDispatcher\EventDispatcher;
 
 /**
  * Get the current user entity object and assign it into the request if it exists.
@@ -18,10 +20,14 @@ class GetCurrentUser
     /** @var Customization */
     protected $customization;
 
-    public function __construct(Auth $auth, Customization $customization)
+    /** @var EventDispatcher */
+    protected $dispatcher;
+
+    public function __construct(Auth $auth, Customization $customization, EventDispatcher $dispatcher)
     {
         $this->auth = $auth;
         $this->customization = $customization;
+        $this->dispatcher = $dispatcher;
     }
 
     /**
@@ -39,6 +45,12 @@ class GetCurrentUser
         $this->customization->setUser($user);
         $request = $this->customization->init($request);
 
+        $this->dispatcher->addListener(BuildView::NAME, function(BuildView $event) use ($user) {
+            $event->getView()->addData([
+                'user' => $user,
+            ]);
+        });
+
         $request = $request
             ->withAttribute(Request::ATTRIBUTE_USER, $user)
             ->withAttribute('is_logged_in', ($user instanceof Entity\User));

src/Plugins.php

@@ -0,0 +1,91 @@
+<?php
+namespace App;
+
+use Composer\Autoload\ClassLoader;
+use Slim\Container;
+use Symfony\Component\EventDispatcher\EventDispatcher;
+use Symfony\Component\Finder\Finder;
+use Symfony\Component\Finder\SplFileInfo;
+
+class Plugins
+{
+    /** @var array An array of all plugins and their capabilities. */
+    protected $plugins = [];
+
+    public function __construct($base_dir)
+    {
+        $this->loadDirectory($base_dir);
+    }
+
+    public function loadDirectory($dir): void
+    {
+        $plugins = (new Finder())
+            ->ignoreUnreadableDirs()
+            ->directories()
+            ->in($dir);
+
+        foreach($plugins as $plugin_dir) {
+            /** @var SplFileInfo $plugin_dir */
+            $plugin_prefix = $plugin_dir->getRelativePathname();
+            $plugin_namespace = 'Plugin\\'.\Doctrine\Common\Inflector\Inflector::classify($plugin_prefix).'\\';
+
+            $this->plugins[$plugin_prefix] = [
+                'namespace' => $plugin_namespace,
+                'path' => $plugin_dir->getPathname(),
+            ];
+        }
+    }
+
+    /**
+     * Add plugin namespace classes (and any Composer dependencies) to the global include list.
+     *
+     * @param ClassLoader $autoload
+     */
+    public function registerAutoloaders(ClassLoader $autoload): void
+    {
+        foreach($this->plugins as $plugin) {
+            $plugin_path = $plugin['path'];
+
+            if (file_exists($plugin_path.'/vendor/autoload.php')) {
+                require($plugin_path.'/vendor/autoload.php');
+            }
+
+            $autoload->addPsr4($plugin['namespace'], $plugin_path.'/src');
+        }
+    }
+
+    /**
+     * Register or override any services contained in the global Dependency Injection container.
+     *
+     * @param Container $di
+     * @param array $settings
+     */
+    public function registerServices(Container $di, array $settings): void
+    {
+        foreach($this->plugins as $plugin) {
+            $plugin_path = $plugin['path'];
+
+            if (file_exists($plugin_path . '/services.php')) {
+                call_user_func(include($plugin_path . '/services.php'), $di, $settings);
+            }
+        }
+    }
+
+    /**
+     * Register custom events that the plugin overrides with the Event Dispatcher.
+     *
+     * @param EventDispatcher $dispatcher
+     * @param Container $di
+     * @param array $settings
+     */
+    public function registerEvents(EventDispatcher $dispatcher, Container $di, array $settings): void
+    {
+        foreach($this->plugins as $plugin) {
+            $plugin_path = $plugin['path'];
+
+            if (file_exists($plugin_path . '/events.php')) {
+                call_user_func(include($plugin_path . '/events.php'), $dispatcher, $di, $settings);
+            }
+        }
+    }
+}

src/Provider/MiddlewareProvider.php

@@ -33,7 +33,8 @@ class MiddlewareProvider implements ServiceProviderInterface
         $di[Middleware\GetCurrentUser::class] = function($di) {
             return new Middleware\GetCurrentUser(
                 $di[App\Auth::class],
-                $di[App\Customization::class]
+                $di[App\Customization::class],
+                $di[\Symfony\Component\EventDispatcher\EventDispatcher::class]
             );
         };
 

src/Provider/SyncProvider.php

@@ -57,8 +57,8 @@ class SyncProvider implements ServiceProviderInterface
                 $di[\App\Radio\AutoDJ::class],
                 $di[\App\Cache::class],
                 $di[\InfluxDB\Database::class],
-                $di[\App\Webhook\Dispatcher::class],
                 $di[\Doctrine\ORM\EntityManager::class],
+                $di[\Symfony\Component\EventDispatcher\EventDispatcher::class],
                 $di[\Monolog\Logger::class]
             );
         };

src/Sync/Task/NowPlaying.php

@@ -2,15 +2,17 @@
 namespace App\Sync\Task;
 
 use App\Cache;
+use App\Event\GenerateRawNowPlaying;
+use App\Event\SendWebhooks;
 use App\Radio\AutoDJ;
 use App\ApiUtilities;
 use App\Radio\Adapters;
-use App\Radio\Frontend\FrontendAbstract;
 use App\Webhook\Dispatcher;
 use Doctrine\ORM\EntityManager;
 use InfluxDB\Database;
 use App\Entity;
 use Monolog\Logger;
+use Symfony\Component\EventDispatcher\EventDispatcher;
 
 class NowPlaying extends TaskAbstract
 {
@@ -32,8 +34,8 @@ class NowPlaying extends TaskAbstract
     /** @var Logger */
     protected $logger;
 
-    /** @var Dispatcher */
+    /** @var EventDispatcher */
-    protected $webhook_dispatcher;
+    protected $event_dispatcher;
 
     /** @var ApiUtilities */
     protected $api_utils;
@@ -54,14 +56,15 @@ class NowPlaying extends TaskAbstract
     protected $analytics_level;
 
     /**
-     * @param EntityManager $em
-     * @param Database $influx
-     * @param Cache $cache
      * @param Adapters $adapters
-     * @param Dispatcher $webhook_dispatcher
      * @param ApiUtilities $api_utils
      * @param AutoDJ $autodj
+     * @param Cache $cache
+     * @param Database $influx
+     * @param EntityManager $em
+     * @param EventDispatcher $event_dispatcher
      * @param Logger $logger
+     *
      * @see \App\Provider\SyncProvider
      */
     public function __construct(
@@ -70,8 +73,8 @@ class NowPlaying extends TaskAbstract
         AutoDJ $autodj,
         Cache $cache,
         Database $influx,
-        Dispatcher $webhook_dispatcher,
         EntityManager $em,
+        EventDispatcher $event_dispatcher,
         Logger $logger)
     {
         $this->adapters = $adapters;
@@ -79,9 +82,9 @@ class NowPlaying extends TaskAbstract
         $this->autodj = $autodj;
         $this->cache = $cache;
         $this->em = $em;
+        $this->event_dispatcher = $event_dispatcher;
         $this->influx = $influx;
         $this->logger = $logger;
-        $this->webhook_dispatcher = $webhook_dispatcher;
 
         $this->history_repo = $this->em->getRepository(Entity\SongHistory::class);
         $this->song_repo = $this->em->getRepository(Entity\Song::class);
@@ -198,27 +201,13 @@ class NowPlaying extends TaskAbstract
         /** @var Entity\Api\NowPlaying|null $np_old */
         $np_old = $station->getNowplaying();
 
+        // Build the new "raw" NowPlaying data.
+        $event = new GenerateRawNowPlaying($station, $frontend_adapter, $remote_adapters, $payload, $include_clients);
+        $this->event_dispatcher->dispatch(GenerateRawNowPlaying::NAME, $event);
+        $np_raw = $event->getRawResponse();
+
         $np = new Entity\Api\NowPlaying;
         $np->station = $station->api($frontend_adapter, $remote_adapters);
-
-        // Build the new "raw" NowPlaying data from the adapters.
-        if (APP_TESTING_MODE) {
-            $np_raw = \NowPlaying\Adapter\AdapterAbstract::NOWPLAYING_EMPTY;
-        } else {
-            $np_raw = $frontend_adapter->getNowPlaying($payload, $include_clients);
-
-            // Loop through all remotes and update NP data accordingly.
-            foreach($remote_adapters as $remote_adapter) {
-                $remote_adapter->updateNowPlaying($np_raw, $include_clients);
-            }
-
-            array_walk($np_raw['current_song'], function(&$value) {
-                $value = htmlspecialchars_decode($value);
-                $value = trim($value);
-            });
-        }
-
-        // Start to convert the "raw" NowPlaying data into the proper API entities.
         $np->listeners = new Entity\Api\NowPlayingListeners($np_raw['listeners']);
 
         if (empty($np_raw['current_song']['text'])) {
@@ -295,8 +284,9 @@ class NowPlaying extends TaskAbstract
         $this->em->persist($station);
         $this->em->flush();
 
-        $np_old = ($np_old instanceof Entity\Api\NowPlaying) ? $np_old : $np;
+        // Trigger the dispatching of webhooks.
-        $this->webhook_dispatcher->dispatch($station, $np_old, $np, ($payload !== null));
+        $webhook_event = new SendWebhooks($station, $np, $np_old, ($payload !== null));
+        $this->event_dispatcher->dispatch(SendWebhooks::NAME, $webhook_event);
 
         $this->logger->popProcessor();
 

src/Webhook/Connector/AbstractConnector.php

@@ -2,6 +2,7 @@
 namespace App\Webhook\Connector;
 
 use App\Entity;
+use App\Event\SendWebhooks;
 use App\Utilities;
 use GuzzleHttp\Client;
 use Monolog\Logger;
@@ -20,14 +21,14 @@ abstract class AbstractConnector implements ConnectorInterface
         $this->http_client = $http_client;
     }
 
-    public function shouldDispatch(array $current_events, array $triggers): bool
+    public function shouldDispatch(SendWebhooks $event, array $triggers): bool
     {
         if (empty($triggers)) {
             return true;
         }
 
         foreach($triggers as $trigger) {
-            if (in_array($trigger, $current_events)) {
+            if ($event->hasTrigger($trigger)) {
                 return true;
             }
         }

src/Webhook/Connector/ConnectorInterface.php

@@ -1,7 +1,7 @@
 <?php
 namespace App\Webhook\Connector;
 
-use App\Entity;
+use App\Event\SendWebhooks;
 
 interface ConnectorInterface
 {
@@ -9,18 +9,17 @@ interface ConnectorInterface
      * Return a boolean indicating whether this connector should dispatch, given the current events
      * that are set to be triggered, and the configured triggers for this connector.
      *
-     * @param array $current_events The events that are currently being triggered.
+     * @param SendWebhooks $event The current webhook dispatching event being evaluated.
      * @param array|null $triggers The configured triggers for this connector.
      * @return bool
      */
-    public function shouldDispatch(array $current_events, array $triggers): bool;
+    public function shouldDispatch(SendWebhooks $event, array $triggers): bool;
 
     /**
      * Trigger the webhook for the specified station, now playing entry, and specified configuration.
      *
-     * @param Entity\Station $station
+     * @param SendWebhooks $event The details of the event that triggered the webhook.
-     * @param Entity\Api\NowPlaying $np_new
+     * @param array $config The specific settings associated with this webhook.
-     * @param array $config
      */
-    public function dispatch(Entity\Station $station, Entity\Api\NowPlaying $np_new, array $config): void;
+    public function dispatch(SendWebhooks $event, array $config): void;
 }

src/Webhook/Connector/Discord.php

@@ -2,6 +2,7 @@
 namespace App\Webhook\Connector;
 
 use App\Entity;
+use App\Event\SendWebhooks;
 use GuzzleHttp\Exception\TransferException;
 use Monolog\Logger;
 
@@ -60,12 +61,7 @@ use Monolog\Logger;
 
 class Discord extends AbstractConnector
 {
-    /**
+    public function dispatch(SendWebhooks $event, array $config): void
-     * @param Entity\Station $station
-     * @param Entity\Api\NowPlaying $np
-     * @param array $config
-     */
-    public function dispatch(Entity\Station $station, Entity\Api\NowPlaying $np, array $config): void
     {
         $webhook_url = $this->_getValidUrl($config['webhook_url'] ?? '');
 
@@ -84,7 +80,7 @@ class Discord extends AbstractConnector
             'footer' => $config['footer'] ?? '',
         ];
 
-        $vars = $this->_replaceVariables($raw_vars, $np);
+        $vars = $this->_replaceVariables($raw_vars, $event->getNowPlaying());
 
         // Compose webhook
         $embed = [

src/Webhook/Connector/Generic.php

@@ -2,17 +2,13 @@
 namespace App\Webhook\Connector;
 
 use App\Entity;
+use App\Event\SendWebhooks;
 use GuzzleHttp\Exception\TransferException;
 use Monolog\Logger;
 
 class Generic extends AbstractConnector
 {
-    /**
+    public function dispatch(SendWebhooks $event, array $config): void
-     * @param Entity\Station $station
-     * @param Entity\Api\NowPlaying $np
-     * @param array $config
-     */
-    public function dispatch(Entity\Station $station, Entity\Api\NowPlaying $np, array $config): void
     {
         $webhook_url = $this->_getValidUrl($config['webhook_url'] ?? '');
 
@@ -26,7 +22,7 @@ class Generic extends AbstractConnector
                 'headers' => [
                     'Content-Type' => 'application/json',
                 ],
-                'json' => $np,
+                'json' => $event->getNowPlaying(),
             ];
 
             if (!empty($config['basic_auth_username']) && !empty($config['basic_auth_password'])) {

src/Webhook/Connector/Local.php

@@ -3,6 +3,7 @@ namespace App\Webhook\Connector;
 
 use App\Cache;
 use App\Entity;
+use App\Event\SendWebhooks;
 use GuzzleHttp\Client;
 use InfluxDB\Database;
 use Monolog\Logger;
@@ -27,33 +28,21 @@ class Local extends AbstractConnector
         $this->settings_repo = $settings_repo;
     }
 
-    /**
+    public function shouldDispatch(SendWebhooks $event, array $triggers): bool
-     * @param array $current_events
-     * @param array|null $triggers
-     * @return bool
-     */
-    public function shouldDispatch(array $current_events, array $triggers): bool
     {
         return true;
     }
 
-    /**
+    public function dispatch(SendWebhooks $event, array $config): void
-     * @param Entity\Station $station
-     * @param Entity\Api\NowPlaying $np
-     * @param array $config
-     * @throws Database\Exception
-     * @throws \InfluxDB\Exception
-     */
-    public function dispatch(Entity\Station $station, Entity\Api\NowPlaying $np, array $config): void
     {
         $this->logger->debug('Writing entry to InfluxDB...');
 
         // Post statistics to InfluxDB.
         $influx_point = new \InfluxDB\Point(
-            'station.' . $station->getId() . '.listeners',
+            'station.' . $event->getStation()->getId() . '.listeners',
             (int)$np->listeners->current,
             [],
-            ['station' => $station->getId()],
+            ['station' => $event->getStation()->getId()],
             time()
         );
 
@@ -67,7 +56,7 @@ class Local extends AbstractConnector
         if ($np_full) {
             foreach($np_full as &$np_row) {
                 /** @var Entity\Api\NowPlaying $np_row */
-                if ($np_row->station->id === $station->getId()) {
+                if ($np_row->station->id === $event->getStation()->getId()) {
                     $np_row = $np;
                 }
 

src/Webhook/Connector/Telegram.php

@@ -1,7 +1,7 @@
 <?php
 namespace App\Webhook\Connector;
 
-use App\Entity;
+use App\Event\SendWebhooks;
 use GuzzleHttp\Exception\TransferException;
 
 /**
@@ -11,12 +11,7 @@ use GuzzleHttp\Exception\TransferException;
  */
 class Telegram extends AbstractConnector
 {
-    /**
+    public function dispatch(SendWebhooks $event, array $config): void
-     * @param Entity\Station $station
-     * @param Entity\Api\NowPlaying $np
-     * @param array $config
-     */
-    public function dispatch(Entity\Station $station, Entity\Api\NowPlaying $np, array $config): void
     {
         $bot_token = $config['bot_token'] ?? '';
         $chat_id = $config['chat_id'] ?? '';
@@ -28,7 +23,7 @@ class Telegram extends AbstractConnector
 
         $messages = $this->_replaceVariables([
             'text' => $config['text'],
-        ], $np);
+        ], $event->getNowPlaying());
 
         try {
             $api_url = (!empty($config['api'])) ? rtrim($config['api'], '/') : 'https://api.telegram.org';

src/Webhook/Connector/TuneIn.php

@@ -2,27 +2,18 @@
 namespace App\Webhook\Connector;
 
 use App\Entity;
+use App\Event\SendWebhooks;
 use GuzzleHttp\Exception\TransferException;
 use Monolog\Logger;
 
 class TuneIn extends AbstractConnector
 {
-    /**
+    public function shouldDispatch(SendWebhooks $event, array $triggers): bool
-     * @param array $current_events
-     * @param array|null $triggers
-     * @return bool
-     */
-    public function shouldDispatch(array $current_events, array $triggers): bool
     {
-        return in_array('song_changed', $current_events);
+        return $event->hasTrigger('song_changed');
     }
 
-    /**
+    public function dispatch(SendWebhooks $event, array $config): void
-     * @param Entity\Station $station
-     * @param Entity\Api\NowPlaying $np
-     * @param array $config
-     */
-    public function dispatch(Entity\Station $station, Entity\Api\NowPlaying $np, array $config): void
     {
         if (empty($config['partner_id']) || empty($config['partner_key']) || empty($config['station_id'])) {
             $this->logger->error('Webhook '.$this->_getName().' is missing necessary configuration. Skipping...');
@@ -32,6 +23,8 @@ class TuneIn extends AbstractConnector
         $this->logger->debug('Dispatching TuneIn AIR API call...');
 
         try {
+            $np = $event->getNowPlaying();
+
             $response = $this->http_client->get('http://air.radiotime.com/Playing.ashx', [
                 'query' => [
                     'partnerId' => $config['partner_id'],

src/Webhook/Connector/Twitter.php

@@ -2,18 +2,14 @@
 namespace App\Webhook\Connector;
 
 use App\Entity;
+use App\Event\SendWebhooks;
 use GuzzleHttp\Exception\TransferException;
 use GuzzleHttp\HandlerStack;
 use Monolog\Logger;
 
 class Twitter extends AbstractConnector
 {
-    /**
+    public function dispatch(SendWebhooks $event, array $config): void
-     * @param Entity\Station $station
-     * @param Entity\Api\NowPlaying $np
-     * @param array $config
-     */
-    public function dispatch(Entity\Station $station, Entity\Api\NowPlaying $np, array $config): void
     {
         if (empty($config['consumer_key'])
             || empty($config['consumer_secret'])
@@ -40,7 +36,7 @@ class Twitter extends AbstractConnector
             'message' => $config['message'] ?? '',
         ];
 
-        $vars = $this->_replaceVariables($raw_vars, $np);
+        $vars = $this->_replaceVariables($raw_vars, $event->getNowPlaying());
 
         // Dispatch webhook
         $this->logger->debug('Posting to Twitter...');

src/Webhook/Dispatcher.php

@@ -3,6 +3,7 @@ namespace App\Webhook;
 
 use App\Config;
 use App\Entity;
+use App\Event\SendWebhooks;
 use App\Exception;
 use App\Provider\WebhookProvider;
 use Monolog\Handler\TestHandler;
@@ -31,12 +32,9 @@ class Dispatcher
     /**
      * Determine which webhooks to dispatch for a given change in Now Playing data, and dispatch them.
      *
-     * @param Entity\Station $station
+     * @param SendWebhooks $event
-     * @param Entity\Api\NowPlaying $np_old
-     * @param Entity\Api\NowPlaying $np_new
-     * @param boolean $is_standalone
      */
-    public function dispatch(Entity\Station $station, Entity\Api\NowPlaying $np_old, Entity\Api\NowPlaying $np_new, $is_standalone = true): void
+    public function dispatch(SendWebhooks $event): void
     {
         if (APP_TESTING_MODE) {
             $this->logger->info('In testing mode; no webhooks dispatched.');
@@ -46,7 +44,7 @@ class Dispatcher
         // Compile list of connectors for the station. Always dispatch to the local websocket receiver.
         $connectors = [];
 
-        if ($is_standalone) {
+        if ($event->isStandalone()) {
             $connectors[] = [
                 'type' => 'local',
                 'triggers' => [],
@@ -55,7 +53,7 @@ class Dispatcher
         }
 
         // Assemble list of webhooks for the station
-        $station_webhooks = $station->getWebhooks();
+        $station_webhooks = $event->getStation()->getWebhooks();
 
         if ($station_webhooks->count() > 0) {
             foreach($station_webhooks as $webhook) {
@@ -70,26 +68,7 @@ class Dispatcher
             }
         }
 
-        // Determine which events should be triggered as a result of this change.
+        $this->logger->debug('Triggering events: '.implode(', ', $event->getTriggers()));
-        $to_trigger = ['all'];
-
-        if ($np_old->now_playing->song->id !== $np_new->now_playing->song->id) {
-            $to_trigger[] = 'song_changed';
-        }
-
-        if ($np_old->listeners->current > $np_new->listeners->current) {
-            $to_trigger[] = 'listener_lost';
-        } elseif ($np_old->listeners->current < $np_new->listeners->current) {
-            $to_trigger[] = 'listener_gained';
-        }
-
-        if ($np_old->live->is_live === false && $np_new->live->is_live === true) {
-            $to_trigger[] = 'live_connect';
-        } elseif ($np_old->live->is_live === true && $np_new->live->is_live === false) {
-            $to_trigger[] = 'live_disconnect';
-        }
-
-        $this->logger->debug('Triggering events: '.implode(', ', $to_trigger));
 
         // Trigger all appropriate webhooks.
         foreach($connectors as $connector) {
@@ -101,10 +80,10 @@ class Dispatcher
             /** @var Connector\ConnectorInterface $connector_obj */
             $connector_obj = $this->connectors->get($connector['type']);
 
-            if ($connector_obj->shouldDispatch($to_trigger, (array)$connector['triggers'])) {
+            if ($connector_obj->shouldDispatch($event, (array)$connector['triggers'])) {
                 $this->logger->debug(sprintf('Dispatching connector "%s".', $connector['type']));
 
-                $connector_obj->dispatch($station, $np_new, (array)$connector['config']);
+                $connector_obj->dispatch($event, (array)$connector['config']);
             }
         }
     }
@@ -135,7 +114,8 @@ class Dispatcher
 
         $np = $station->getNowplaying();
 
-        $connector_obj->dispatch($station, $np, $webhook_config);
+        $event = new SendWebhooks($station, $np);
+        $connector_obj->dispatch($event, $webhook_config);
 
         $this->logger->popHandler();