Merge pull request #928 from carstingaxion/feature/fragment-of-pr-831…

…-endpoint-base

new calendar endpoints | part 2/4 | endpoint base

includes/core/classes/class-autoloader.php

@@ -89,6 +89,7 @@ static function ( string $class_string = '' ): void {
 					switch ( $class_type ) {
 						case 'blocks':
 						case 'commands':
+						case 'endpoints':
 						case 'settings':
 						case 'traits':
 							array_pop( $structure );

includes/core/classes/endpoints/class-endpoint-redirect.php

@@ -0,0 +1,94 @@
+<?php
+/**
+ * Class responsible for handling redirect-based endpoints in GatherPress.
+ *
+ * This file defines the `Endpoint_Redirect` class, which extends the base `Endpoint_Type`
+ * class and manages URL redirection for specific endpoints. It safely redirects users
+ * to external URLs based on the logic provided by the callback function, while ensuring
+ * the redirection is secure and follows WordPress's allowed hosts policy.
+ *
+ * @package GatherPress\Core\Endpoints
+ * @since 1.0.0
+ */
+
+namespace GatherPress\Core\Endpoints;
+
+// Exit if accessed directly.
+defined( 'ABSPATH' ) || exit; // @codeCoverageIgnore
+
+use GatherPress\Core\Endpoints\Endpoint;
+
+/**
+ * Handles safe URL redirection for custom endpoints in GatherPress.
+ *
+ * The `Endpoint_Redirect` class extends the `Endpoint_Type` class and is responsible
+ * for managing URL redirection for specific endpoints. It handles:
+ * - Getting the redirect URL through a callback.
+ * - Safely redirecting users using `wp_safe_redirect()`.
+ * - Filtering allowed redirect hosts to ensure security.
+ *
+ * @since 1.0.0
+ */
+class Endpoint_Redirect extends Endpoint_Type {
+
+	/**
+	 * The target URL for the redirection.
+	 *
+	 * This property stores the URL that the user will be redirected to when the endpoint
+	 * is triggered. The URL is generated by calling the callback function provided during
+	 * the endpoint's construction.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @var string
+	 */
+	protected $url;
+
+	/**
+	 * Activate Endpoint_Type by hooking into relevant parts.
+	 *
+	 * Safely redirects the user to the specified URL.
+	 *
+	 * This method gets the target URL by calling the callback function and then
+	 * safely redirects the user to that URL using `wp_safe_redirect()`.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param Endpoint|null $endpoint Class for custom rewrite endpoints and their query handling in GatherPress.
+	 * @return void
+	 */
+	public function activate( ?Endpoint $endpoint = null ): void {
+		$this->url = ( $this->callback )();
+		if ( $this->url ) {
+			// Add the target host to the list of allowed redirect hosts.
+			add_filter( 'allowed_redirect_hosts', array( $this, 'allowed_redirect_hosts' ) );
+			// Perform a safe redirection to the target URL. Defaults to a 302 status code.
+			wp_safe_redirect( $this->url );
+			exit; // Always exit after redirecting.
+		}
+	}
+
+	/**
+	 * Filters the list of allowed hosts to include the redirect target.
+	 *
+	 * This method ensures that the host of the target URL is added to the list of allowed
+	 * redirect hosts, allowing the redirection to proceed safely. It is hooked into the
+	 * `allowed_redirect_hosts` filter, which controls the domains that `wp_safe_redirect()`
+	 * is allowed to redirect to.
+	 *
+	 * @see https://developer.wordpress.org/reference/hooks/allowed_redirect_hosts/
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param string[] $hosts An array of allowed host names.
+	 * @return string[]       The updated array of allowed host names, including the redirect target.
+	 */
+	public function allowed_redirect_hosts( array $hosts ): array {
+		return array_merge(
+			$hosts,
+			array(
+				wp_parse_url( $this->url, PHP_URL_HOST ),
+			)
+		);
+	}
+}

includes/core/classes/endpoints/class-endpoint-template.php

@@ -0,0 +1,210 @@
+<?php
+/**
+ * Class responsible for handling template-based endpoints in GatherPress.
+ *
+ * This file defines the `Endpoint_Template` class, which extends the base `Endpoint_Type` class
+ * and manages custom templates for endpoints. It allows themes to override the default plugin
+ * templates by checking the theme's template directory before falling back to the plugin's template.
+ *
+ * @package GatherPress\Core\Endpoints
+ * @since 1.0.0
+ */
+
+namespace GatherPress\Core\Endpoints;
+
+// Exit if accessed directly.
+defined( 'ABSPATH' ) || exit; // @codeCoverageIgnore
+
+use GatherPress\Core\Endpoints\Endpoint;
+use GatherPress\Core\Utility;
+
+/**
+ * Handles template rendering for custom endpoints in GatherPress.
+ *
+ * The `Endpoint_Template` class extends the `Endpoint_Type` class and is responsible
+ * for loading custom templates for specific endpoints. It allows for theme-based
+ * overrides, giving themes the ability to provide their own template files for the
+ * endpoints instead of using the default plugin templates.
+ *
+ * - It checks if a template exists in the current theme or child theme.
+ * - If not found, it falls back to the template provided by the plugin.
+ *
+ * @since 1.0.0
+ */
+class Endpoint_Template extends Endpoint_Type {
+
+	/**
+	 * Directory path for plugin templates.
+	 *
+	 * @var string
+	 */
+	protected $plugin_template_dir;
+
+	/**
+	 * Class constructor.
+	 *
+	 * Initializes the `Endpoint_Template` object by setting the slug, callback, and
+	 * plugin template directory. The parent constructor initializes the slug and callback,
+	 * while this constructor adds the plugin template default.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param string   $slug                The slug used to identify the endpoint in the URL.
+	 * @param callable $callback            The callback function to retrieve file name and path of the endpoint template.
+	 * @param string   $plugin_template_dir The directory path for the plugin templates.
+	 */
+	public function __construct( string $slug, callable $callback, string $plugin_template_dir = '' ) {
+		parent::__construct( $slug, $callback );
+		$this->plugin_template_dir = ( ! empty( $plugin_template_dir ) ) ? $plugin_template_dir : sprintf(
+			'%s/includes/templates/endpoints',
+			GATHERPRESS_CORE_PATH
+		);
+	}
+
+
+	/**
+	 * Activate Endpoint_Type by hooking into relevant parts.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param Endpoint|null $endpoint Class for custom rewrite endpoints and their query handling in GatherPress.
+	 * @return void
+	 */
+	public function activate( ?Endpoint $endpoint = null ): void {
+
+		// A call to any /feed/ endpoint is handled different by WordPress
+		// and as such the 'Endpoint_Template's template_include hook would fail.
+		$feed_slug = ( null !== $endpoint ) ? $endpoint->has_feed() : false;
+		if ( $feed_slug ) {
+			// Hook into WordPress' feed handling to load the custom feed template.
+			add_action( sprintf( 'do_feed_%s', $feed_slug ), array( $this, 'load_feed_template' ) );
+		} else {
+			// Filters the path of the current template before including it.
+			add_filter( 'template_include', array( $this, 'template_include' ) );
+		}
+	}
+
+	/**
+	 * Load the theme-overridable feed template from the plugin.
+	 *
+	 * This method ensures that a feed template is loaded when a request is made to
+	 * a custom feed endpoint. If the theme provides an override for the feed template,
+	 * it will be used; otherwise, the default template from the plugin is loaded. The
+	 * method ensures that WordPress does not return a 404 for custom feed URLs.
+	 *
+	 * A call to any post types /feed/anything endpoint is handled by WordPress
+	 * prior 'Endpoint_Template's template_include hook would run.
+	 * Therefore WordPress will throw an xml'ed 404 error,
+	 * if nothing is hooked onto the 'do_feed_anything' action.
+	 *
+	 * That's the reason for this method, it delivers what WordPress wants
+	 * and re-uses the parameters provided by the class.
+	 *
+	 * We expect that a endpoint, that contains the /feed/ string, only has one 'Redirect_Template' attached.
+	 * This might be wrong or short sightened, please open an issue in that case: https://github.com/GatherPress/gatherpress/issues
+	 *
+	 * Until then, we *just* use the first of the provided endpoint-types,
+	 * to hook into WordPress, which should be the valid template endpoint.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @return void
+	 */
+	public function load_feed_template() {
+		load_template( $this->template_include() );
+	}
+
+	/**
+	 * Filters the path of the current template before including it.
+	 *
+	 * This method checks if the theme or child theme provides a custom template for the
+	 * current endpoint. If a theme template exists, it will use that; otherwise, it will
+	 * fall back to the default template provided by the plugin. The template information
+	 * is provided by the callback set during the construction of the endpoint.
+	 *
+	 * @since 1.0.0
+	 *
+	 * @param string $template The path of the default template to include,
+	 *                         defaults to '' so that the template loader keeps looking for templates.
+	 * @return string          The path of the template to include, either from the theme or plugin.
+	 */
+	public function template_include( string $template = '' ): string {
+		$presets = $this->get_template_presets();
+
+		$file_name = $presets['file_name'];
+		$dir_path  = $presets['dir_path'] ?? $this->plugin_template_dir;
+
+		// Check if the theme provides a custom template.
+		$theme_template = $this->get_template_from_theme( $file_name );
+		if ( $theme_template ) {
+			return $theme_template;
+		}
+
+		// Check if the plugin has a template file.
+		$plugin_template = $this->get_template_from_plugin( $file_name, $dir_path, );
+		if ( $plugin_template ) {
+			return $plugin_template;
+		}
+
+		// Fallback to the default template.
+		return $template;
+	}
+
+
+	/**
+	 * Retrieve template presets by invoking the callback.
+	 *
+	 * @return array Template preset data including file_name and optional dir_path.
+	 */
+	protected function get_template_presets(): array {
+		return ( $this->callback )();
+	}
+
+	/**
+	 * Locate a template in the theme or child theme.
+	 *
+	 * @todo Maybe better put in the Utility class?
+	 *
+	 * @param string $file_name The name of the template file.
+	 * @return string The path to the theme template or an empty string if not found.
+	 */
+	protected function get_template_from_theme( string $file_name ): string {
+
+		// locate_template() doesn't cares,
+		// but locate_block_template() needs this to be an array.
+		$templates = array( $file_name );
+
+		// First, search for PHP templates, which block themes can also use.
+		$template = locate_template( $templates );
+
+		// Pass the result into the block template locator and let it figure
+		// out whether block templates are supported and this template exists.
+		$template = locate_block_template(
+			$template,
+			pathinfo( $file_name, PATHINFO_FILENAME ), // Name of the file without extension.
+			$templates
+		);
+
+		return $template;
+	}
+
+	/**
+	 * Build the full path to the plugin's template file.
+	 *
+	 * @todo Maybe better put in the Utility class?
+	 *
+	 * @param string $file_name The name of the template file.
+	 * @param string $dir_path  The directory path where the template is stored.
+	 * @return string The full path to the template file or an empty string if file not exists.
+	 */
+	protected function get_template_from_plugin( string $file_name, string $dir_path ): string {
+		// Remove prefix to keep file-names simple,
+		// for templates of core GatherPress.
+		if ( $this->plugin_template_dir === $dir_path ) {
+			$file_name = Utility::unprefix_key( $file_name );
+		}
+
+		$template = trailingslashit( $dir_path ) . $file_name;
+		return file_exists( $template ) ? $template : '';
+	}
+}