Create index.php

Author: orthagonal

index.php

@@ -0,0 +1,145 @@
+<?php
+/**
+ * @package Unique_WP_Query
+ * @version 1.0.0
+ */
+/*
+Plugin Name: Unique WP Query
+Plugin URI: https://github.com/firstandthird/unique_wp_query
+Description: A plugin for doing unique WP_Query
+Author: firstandthird
+Version: 1.0.0
+*/
+// adapted & taken from from https://gist.github.com/jameswburke/d0776d742ab74c469cd8af8dacd916fc
+
+/**
+ * Wrapper for WP_Query
+ * Interacts directly with WP_Query_Manager to ensure
+ * only unique posts are ever returned.
+ *
+ * Known issues:
+ * Won't work with offset values
+ */
+class Unique_WP_Query extends WP_Query {
+	function __construct($args) {
+		// Act as a flag for pre_get_posts
+		$args['unique_wp_query'] = true;
+
+		// Initialize the WP_Query object like normal
+		parent::__construct($args);
+
+		// Track used posts, and remove duplicates
+		Unique_WP_Query_Manager::process_posts($this->posts, $this->post_count, $this->get('original_posts_per_page'));
+	}
+}
+
+/**
+ * Keeps track of which posts have already appeared and
+ * removes them from future Unique_WP_Query objects.
+ */
+class Unique_WP_Query_Manager {
+
+	/**
+	 * Keep track of which post_ids have already been used
+	 * @var array
+	 */
+	public static $used_post_ids = [];
+
+	/**
+	 * Keeps track of how many used_posts_ids exist
+	 * @var integer
+	 */
+	public static $used_post_count = 0;
+
+  /**
+   * Helper to make sure no duplicate ids are added
+   * useful for content outside of the normal query
+   */
+  public static function add_post_id($id) {
+    if (!in_array($id, Unique_WP_Query_Manager::$used_post_ids, true)) {
+      Unique_WP_Query_Manager::$used_post_ids[] = $id;
+      Unique_WP_Query_Manager::$used_post_count = count(Unique_WP_Query_Manager::$used_post_ids);
+    }
+  }
+
+	/**
+	 * Takes the posts and post count of a WP_Query object and
+	 * ensures that it removes posts that have already been used,
+	 * and then trims it to the necessary size.
+	 *
+	 * @param array &$posts
+	 * @param integer &$post_count
+	 */
+	public static function process_posts(&$posts, &$post_count, $original_posts_per_page) {
+
+		// Keep track of how many posts are acceptable to return
+		$current_accepted_post_count = 0;
+
+		// Make sure we have posts
+		if (empty((array) $posts)) {
+			return;
+		}
+
+		// Loop through all the found posts
+		foreach ((array) $posts as $key => $post) {
+
+			// If we have enough acceptable posts, break the loop
+			// Otherwise, determine if we've already used this post
+			if ($original_posts_per_page > $current_accepted_post_count) {
+
+				// Has this post already been used?
+				if (in_array($post->ID, Unique_WP_Query_Manager::$used_post_ids, true)) {
+					// Remove from $posts
+					unset($posts[$key]);
+
+					// And update count
+					$post_count--;
+				} else {
+					// If not, add it to the list of used ids
+					Unique_WP_Query_Manager::$used_post_ids[] = $post->ID;
+
+					// Update how many accepted posts we have
+					$current_accepted_post_count++;
+				}
+			} else {
+				// If we have enough acceptable posts, break the foreach
+				// This prevents extra results from accidently being added to $used_post_ids
+				break;
+			}
+		}
+
+		// Reindex the array correctly
+		$posts = array_values($posts);
+
+		// Update the $used_post_count
+		Unique_WP_Query_Manager::$used_post_count = count(Unique_WP_Query_Manager::$used_post_ids);
+
+		// Trim any excess posts and update $post_count
+		if (count($posts) > $original_posts_per_page) {
+
+			// Remove extra posts
+			$posts = array_slice($posts, 0, $original_posts_per_page);
+
+			// Update post count to our new value
+			$post_count = $original_posts_per_page;
+		}
+	}
+}
+
+if (!function_exists('unique_wp_query_pre_get_posts')) {
+	/**
+	 * Increase the posts_per_page value by the number of posts that have
+	 * already been used. Executes as the last pre_get_posts action.
+	 */
+	function unique_wp_query_pre_get_posts(&$query) {
+		if (true === $query->get('unique_wp_query')) {
+			$posts_per_page = $query->get('posts_per_page');
+
+      // Increase posts_per_page by the amount of used post_ids
+      $query->set('original_posts_per_page', min($posts_per_page, 200));
+      $query->set('posts_per_page', min($posts_per_page + Unique_WP_Query_Manager::$used_post_count, 200));
+		}
+	}
+
+	add_action('pre_get_posts', 'unique_wp_query_pre_get_posts', PHP_INT_MAX);
+}