WordPress Discourse Reply Count Update Script

discourse-reply-count.php

<?php
// This script will look at ALL of your WordPress blog posts (post type 'post' in this case)
//  and look at the reported number of comments in the post's meta / custom_field, 'pp_discourse_replies'
//
// It will then look at all associated Discourse Topics (as per the WP-Discourse plugin's discourse_topic_id) 
//  custom field and and check the actual number of replies. If they are different, it will update the custom field.
//
// You can then override your WP theme's comment count PHP to display this meta field (pp_discourse_replies)
//  and run this script on cron, so you have regularly-updated comment counts, but are not slowing your site down
//  retrieving them.
//
// This allows you to use embedded JS comments and is a HYBRID solution with WP-Discourse plugin that does NOT
//  need to have the actual comments pulled into WordPress. But we do need the Topic IDs set in the
//  discourse_topic_id custom field for each post.
//  https://meta.discourse.org/t/embedding-discourse-comments-via-javascript/31963
// 
// This script requires cron to call it.  It doesn't run via WP cron
//  or really work inside of any WordPress installation

/*
 * Site and Product Configs
 */
$_SERVER[ 'HTTP_HOST' ] = 'blog.YOURDOMAIN.com';
$wp_load_loc = "/PATH/TO/YOUR/WORDPESS/public_html/wp-load.php";

require_once($wp_load_loc);

//test to make sure we can access database
//echo $wpdb->prefix . "\n";

$discourse_api_key = 'YOUR_API_KEY_FOR_DISCOURSE';
$discourse_api_user = "YOUR_API_USER_FOR_DISCOURSE";

echo "Getting meta values...\n";

// See the get_meta_values function below. If you care about other types of post
//  types, you may need to tweak it
$discourse_posts = get_meta_values('discourse_topic_id','post');

echo "Retrieved " . count($discourse_posts) . " meta values\n";
$update_count = 0;
$error_count = 0;

foreach ($discourse_posts as $post_id => $topic_id) {
  $request_url = "https://forum.priceplow.com/t/" . $topic_id . ".json?api_key=" . $discourse_api_key . '&api_user=' . $discourse_api_user;
  $download_success = FALSE;
  $fail_count = 0;
  while (!$download_success && $fail_count < 5) {
    $topic_data = wp_remote_get($request_url);
    if (is_array($topic_data)) {
      $body_json = $topic_data['body'];
      $data = json_decode($body_json, TRUE);
      $num_replies = $data['posts_count'] - 1; // This is the number of total actual REPLIES a topic has gotten
      
      if($num_replies >= 0) {
        $success = update_post_meta($post_id, 'pp_discourse_replies', $num_replies);
        if($success === TRUE) {
          $update_count++;
          echo " Updated Post " . $post_id . " with " . $num_replies . " replies for https://forum.priceplow.com/t/" . $topic_id . "\n";
        } elseif (isInteger($success)) {
          // When update_post_meta returns something outside of boolean, that means it created a new one, returning its new meta_id
          echo " Added NEW Post " . $post_id . " with " . $num_replies . " replies for https://forum.priceplow.com/t/" . $topic_id . "\n";
          $update_count++;
        }
        $download_success = TRUE;
      } else {
        // Sometimes you get negative replies from Discourse. This means it wasn't a good download.
        echo " Warning: Negative replies for $request_url\n";
        $download_success = FALSE;
        $fail_count++;
        sleep(3);
      }
    } else {
      echo " Warning: Array Not Returned for $request_url\n";
      $fail_count++;
      sleep(3);
    }
    if($fail_count == 5) {
      echo "\n\n\tERROR: FIVE FAILURES FOR $request_url\n\n";
      $error_count++;
    }
  }
}

error_log("Discourse Comment Run: Updated " . $update_count . " posts with " . $error_count . " Unrecoverable Errors");

// Not sure if this matters for cron
if($error_count > 0) {
  return FALSE;
} elseif ($update_count == 0) {
  return TRUE; // Not sure what happens when 0 returned to bash
} else {
  return $update_count;
}


// function to grab all possible meta values of the chosen meta key.
//  Returns as an associative array indexed with the post ID
// If you care about multiple post_types, you may want to change it into an array.
function get_meta_values( $meta_key,  $post_type = 'post' ) {

    $posts = get_posts(
        array(
            'post_type' => $post_type,
            'meta_key' => $meta_key,
            'posts_per_page' => -1,
        )
    );

    $meta_values = array();
    foreach( $posts as $post ) {
        $meta_values[$post->ID] = get_post_meta( $post->ID, $meta_key, true );
    }

    return $meta_values;
}

// From http://php.net/manual/en/function.is-int.php
function isInteger($input) {
    return(ctype_digit(strval($input)));
}
?>