WordPress Deployments: Example of Database Changes in Code

/*
Plugin Name: Deployment routines
Description: Runs update routines allowing code based database updates.
Author: Andy Mantell
Version: 1.0
*/
add_action( 'admin_init', 'deployment_admin_init' );
 
/**
 * Attached to init. Runs any necessary update routines
 */
function deployment_admin_init() {
 
  // What is the current version of this plugin?
  $deployment_version = 1;
 
  // What is the current version in the db
  $db_version = get_option( 'deployment_version', 0 );
 
  // Is the db out of date?
  if ( $db_version < $deployment_version ) {
 
    // If so, loop over all subsequent version numbers and attempt to run corresponding deployment_update_N functions
    for ( $version = $db_version + 1; $version <= $deployment_version; $version ++ ) {
      if ( function_exists( 'deployment_update_' . $version ) ) {
        $success = call_user_func( 'deployment_update_' . $version );
 
        // If the function returns a boolean false, log an error and bail out. Subsequent updates may rely on this update
        // so we shouldn't proceed any further.
        if ( $success === FALSE ) {
          // @TODO: log error here
          break;
        }
      }
 
      // If we've reached this far without error, update the db version
      update_option( 'deployment_version', $version );
    }
 
    // @TODO: output update summary on success
  }
}
 
/**
 * Update functions.
 */
 
/**
 * Disable the wordpress-meta-description plugin.
 * Enable and configure the add-meta-tags plugin
 */
function deployment_update_1() {
 
  // Include the plugin.php file so you have access to the activate_plugin() function
  require_once( ABSPATH . '/wp-admin/includes/plugin.php' );
 
  deactivate_plugins( WP_PLUGIN_DIR . '/wordpress-meta-description/wp-meta-description.php' );
  activate_plugins( WP_PLUGIN_DIR . '/add-meta-tags/add-meta-tags.php' );
 
  update_option( 'add_meta_tags_opts', array(
    'settings_version' => 2,
    'site_description' => 'Site description here',
    'site_keywords' => 'site, keywords, here',
    'global_keywords' => 'global, keywords, here',
    'site_wide_meta' => '',
    'auto_description' => '1',
    'auto_keywords' => '1',
    'auto_opengraph' => '0',
    'auto_dublincore' => '0',
    'noodp_description' => '0',
    'noindex_search_results' => '1',
    'noindex_date_archives' => '0',
    'noindex_category_archives' => '0',
    'noindex_tag_archives' => '0',
    'noindex_author_archives' => '0',
    'copyright_url' => '',
    'default_image_url' => '',
    'i_have_donated' => '0',
  ) );
 
  return TRUE;
}

/*
Plugin Name: MTM WordPress Deployment Updates
Description: Runs update routines allowing code based database updates.
Author: Metal Toad Media
Version: 1.0
*/
add_action( 'admin_init', 'deployment_admin_init' );
 
/**
 * Attached to init. Runs any necessary update routines
 */
function deployment_admin_init() {
 
  // What is the current version of this plugin?
  $deployment_version = 3;
 
  // What is the current version in the db
  $db_version = get_option( 'deployment_version', 0 );
 
  // Is the db out of date?
  if ( $db_version < $deployment_version ) {
 
    // If so, loop over all subsequent version numbers and attempt to run corresponding deployment_update_N functions
    for ( $version = $db_version + 1; $version <= $deployment_version; $version ++ ) {
      if ( function_exists( 'deployment_update_' . $version ) ) {
        $success = call_user_func( 'deployment_update_' . $version );
 
        // If the function returns a boolean false, log an error and bail out. Subsequent updates may rely on this update
        // so we shouldn't proceed any further.
        if ( $success === FALSE ) {
          // @TODO: log error here
          break;
        }
      }
 
      // If we've reached this far without error, update the db version
      update_option( 'deployment_version', $version );
    }
 
    // @TODO: output update summary on success
  }
}
 
/**
 * Update functions.
 */
 
/**
 * Disable the wordpress-meta-description plugin.
 * Enable and configure the add-meta-tags plugin
 */
function deployment_update_1() {
 
  // Include the plugin.php file so you have access to the activate_plugin() function
  require_once( ABSPATH . '/wp-admin/includes/plugin.php' );
 
  deactivate_plugins( WP_PLUGIN_DIR . '/wordpress-meta-description/wp-meta-description.php' );
  activate_plugins( WP_PLUGIN_DIR . '/add-meta-tags/add-meta-tags.php' );
 
  update_option( 'add_meta_tags_opts', array(
    'settings_version' => 2,
    'site_description' => 'Metal Toad Media',
    'site_keywords' => 'Phylum‎: ‎Chordata, Kingdom‎: ‎Animalia, Class‎: ‎Amphibia',
    'global_keywords' => 'boreal, arroyo, amargosa',
    'site_wide_meta' => '',
    'auto_description' => '1',
    'auto_keywords' => '1',
    'auto_opengraph' => '0',
    'auto_dublincore' => '0',
    'noodp_description' => '0',
    'noindex_search_results' => '1',
    'noindex_date_archives' => '0',
    'noindex_category_archives' => '0',
    'noindex_tag_archives' => '0',
    'noindex_author_archives' => '0',
    'copyright_url' => '',
    'default_image_url' => '',
    'i_have_donated' => '0',
  ) );
 
  return TRUE;
}
 
// Add another user
function deployment_update_2() {
 
  wp_create_user( 'trevor', 'thefr0g', 'trevor@nospam.dev' );
 
  return TRUE;
}
 
// Add table to the database
// https://codex.wordpress.org/Creating_Tables_with_Plugins
function deployment_update_3() {
 
  global $mtm_db_version;
  $mtm_db_version = '1.0';
 
    global $wpdb;
    global $mtm_db_version;
 
    $table_name = $wpdb->prefix . 'mtm_toads';
 
    $charset_collate = $wpdb->get_charset_collate();
 
    $sql = "CREATE TABLE $table_name (
      id mediumint(9) NOT NULL AUTO_INCREMENT,
      time datetime DEFAULT '0000-00-00 00:00:00' NOT NULL,
      name tinytext NOT NULL,
      text text NOT NULL,
      url varchar(55) DEFAULT '' NOT NULL,
      UNIQUE KEY id (id)
    ) $charset_collate;";
 
    require_once( ABSPATH . 'wp-admin/includes/upgrade.php' );
    dbDelta( $sql );
 
    add_option( 'mtm_db_version', $mtm_db_version );
}