[Wordpress] Custom importer class

importer.php

<?php 
/**
 * FM_Importer
 * Author: Mattias Ghodsian
 * Donate a cup of coffee: https://www.buymeacoffee.com/mattiasghodsian
 * Donate Eth: 0xBBB96204E45D11C9799c6B12E6eE6F0d4A071Ef5
 */
if ( ! defined( 'ABSPATH' ) ) { exit; }

if ( ! defined( 'WP_LOAD_IMPORTERS' ) )
    return;

// Load Importer API
require_once ABSPATH . 'wp-admin/includes/import.php';

if ( ! class_exists( 'WP_Importer' ) ) {
	$class_wp_importer = ABSPATH . 'wp-admin/includes/class-wp-importer.php';
	if ( file_exists( $class_wp_importer ) )
		require $class_wp_importer;
}

if ( !class_exists( 'FM_Importer' ) ) {
	class FM_Importer extends WP_Importer {

		var $id;
		var $import_data;
		var $users;

		/**
		 * construct do nothing
		 *
		 * @since 1.0.0
		 * @return html
		 */
		function __construct() { 

		}

		/**
		 * Core of the importer
		 *
		 * @since 1.0.0
		 * @return html
		 */
		function dispatch() {
			$this->header();

			$step = empty( $_GET['step'] ) ? 0 : (int) $_GET['step'];
			switch ( $step ) {
				case 0:
					$this->greet();
					break;
				case 1:
					check_admin_referer( 'import-upload' );
					if ( $this->handle_upload() ){
						$this->get_users();
						$this->import_options();
					}
					break;
				case 2:
					check_admin_referer( 'import-fm-ga' );
					$this->id = (int) $_POST['import_id'];
					$file = get_attached_file( $this->id );
					set_time_limit(0);
					$this->import( $file );
					break;
			}

			$this->footer();
		}

		/**
		 * Display import page title
		 *
		 * @since 1.0.0
		 * @return html
		 */
		function header() {
			echo '<div class="wrap">';
			screen_icon();
			echo '<h2>' . __( 'Import Google Analytics', 'forfragan' ) . '</h2>';
		}

		/**
		 * Close div.wrap
		 *
		 * @since 1.0.0
		 * @return html
		 */
		function footer() {
			echo '</div>';
		}

		/**
		 * Display introductory text and file upload form
		 *
		 * @since 1.0.0
		 * @return html
		 */
		function greet() {
			echo '<div class="narrow">';
			echo '<p>'.__( 'Howdy! Upload your Google Analytics (.csv) file and we&#8217;ll import the data into this site.', 'forfragan' ).'</p>';
			wp_import_upload_form( 'admin.php?import=fm_ga&amp;step=1' );
			echo '</div>';
		}

		/**
		 * Handles the CSV upload and initial parsing of the file to prepare for
		 * displaying author import options
		 *
		 * @return bool
		 */
		function handle_upload() {
			$file = wp_import_handle_upload();

			if ( isset( $file['error'] ) ) {
				echo '<p><strong>' . __( 'Sorry, there has been an error.', 'forfragan' ) . '</strong><br />';
				echo esc_html( $file['error'] ) . '</p>';
				return false;
			} else if ( ! file_exists( $file['file'] ) ) {
				echo '<p><strong>' . __( 'Sorry, there has been an error.', 'forfragan' ) . '</strong><br />';
				printf( __( 'The export file could not be found at <code>%s</code>. It is likely that this was caused by a permissions problem.', 'forfragan' ), esc_html( $file['file'] ) );
				echo '</p>';
				return false;
			}

			$this->id = (int) $file['id'];
			$import_data = $this->parse( $file['file'] );
			$fileParts = pathinfo($file['file']);

			if ( is_wp_error( $import_data ) ) {
				echo '<p><strong>' . __( 'Sorry, there has been an error.', 'forfragan' ) . '</strong><br />';
				echo esc_html( $import_data->get_error_message() ) . '</p>';
				return false;
			}

			if ( $fileParts['extension'] !== "txt" ) {
				echo '<p><strong>' . __( 'Sorry, this is not a CSV file.', 'forfragan' ) . '</strong><br />';
				return false;
			}

			return true;
		}

		/**
		 * Get users with venue slugs
		 *
		 * @since 1.0.0
		 * @return array
		 */
		function get_users(){
			$query = new \WP_User_Query();
		    $meta_query = array(
		        'key'     => 'venue_slugs', // field_5f8d9ff578d40 
		        'value'   => false,
		        'compare' => '!='
		    );

		    $query->prepare_query([
		        'meta_key' => 'venue_slugs', // field_5f8d9ff578d40
		        'meta_query' => $meta_query
		    ]);

		    $query->query();
		    $users = $query->get_results();

		    $u = array_map(function($user) {
		        $data =  get_field('field_5f8d9ff578d40','user_'.$user->ID);
		        $slugs = [];
		        foreach ($data[0] as $key => $row) {
		            $slugs[] = $row;
		        }
		        return ['ID' => $user->ID, 'email' => $user->user_email, 'slugs' => $slugs ];
		    }, $users);

		    $this->users = array_filter($u);
		}

		/**
		 * Parses the CSV file and prepares us for the task of processing parsed data
		 *
		 * @since 1.0.0
		 * @param string $file Path to the CSV file for importing
		 * @return null
		 */
		function import_start( $file ) {
			if ( ! is_file($file) ) {
				echo '<p><strong>' . __( 'Sorry, there has been an error.', 'forfragan' ) . '</strong><br />';
				echo __( 'The file does not exist, please try again.', 'forfragan' ) . '</p>';
				$this->footer();
				die();
			}

			$import_data = $this->parse( $file );

			if ( is_wp_error( $import_data ) ) {
				echo '<p><strong>' . __( 'Sorry, there has been an error.', 'forfragan' ) . '</strong><br />';
				echo esc_html( $import_data->get_error_message() ) . '</p>';
				$this->footer();
				die();
			}

			unset($import_data[0],$import_data[1],$import_data[2],$import_data[3],$import_data[4],$import_data[5],$import_data[6]);

			$this->import_data = $import_data;

			do_action( 'import_start' );
		}

		/**
		 * Parse a CSV file
		 *
		 * @since 1.0.0
		 * @param string $file Path to CSV file for parsing
		 * @return array Information gathered from the CSV file
		 */
		function parse( $file ) {
			$parser = array_map('str_getcsv', file($file));
			return $parser;
		}

		/**
		 * The main controller for the actual import stage.
		 *
		 * @since 1.0.0
		 * @param string $file Path to the CSV file for importing
		 * @return null
		 */
		function import( $file ) {
			add_filter( 'http_request_timeout', array( &$this, 'bump_request_timeout' ) );
			$this->import_start( $file );
			$this->process_posts();
			$this->import_end();
		}

		/**
		 * Performs post-import cleanup of files and the cache
		 *
		 * @since 1.0.0
		 * @return null
		 */
		function import_end() {
			wp_import_cleanup( $this->id );
			wp_cache_flush();

			echo '<p>' . __( 'Import done.', 'forfragan' ) . ' <a href="' . admin_url() . '">' . __( 'Have fun!', 'wordpress-importer' ) . '</a>' . '</p>';
			do_action( 'import_end' );
		}

		/**
		 * Create new posts based on import information
		 *
		 * @since 1.0.0
		 * @return null
		 */
		function process_posts() {
			$success 	= 0;
			$errors 	= 0;
			$data 		= $this->import_data;

			foreach ($data as $key => $row) {
				
				$post = wp_insert_post([
					'post_type' => 'analytics', 
					'post_status' => 'publish', 
					'post_author' => 1 , 
					'post_title' => $row[0]
				]);

				if ($post) {
					update_field('page_views',$row[1], $post);
					update_field('unique_page_views',$row[2], $post);
					update_field('time_on_page',$row[3], $post);
					update_field('entrances',$row[4], $post);
					update_field('bounce_rate',$row[5], $post);
					update_field('exit',$row[6], $post);
					update_field('page_value',str_replace('SEK ', '', $row[7]), $post);
					$success++;
				}else{
					$errors++;
				}

			}

			dump( $data );            
			?>	
			<p><?= __('Imported', 'forfragan');?> <?= $success; ?> <?= __('and', 'forfragan'); ?> <?= $errors; ?> <?= __('rejected', 'forfragan'); ?></p>
			<?php  
		}

		/**
		 * Display pre-import information
		 *
		 * @since 1.0.0
		 * @return null
		 */
		function import_options() {
			?>
			<form action="<?php echo admin_url( 'admin.php?import=fm_ga&amp;step=2' ); ?>" method="post">
				<?php wp_nonce_field( 'import-fm-ga' ); ?>
				<input type="hidden" name="import_id" value="<?php echo $this->id; ?>" />
				<p><?= __('Found:', 'forfragan'); ?> <?= count($this->users); ?> <?= __('user(s)', 'forfragan'); ?></p>
				<p><?= __( 'The imported content will be assign to the user(s) by there venue slug', 'forfragan' ); ?></p>
				<p><?= __( 'Are you sure you want to import the data ?', 'forfragan' ); ?></p>
				<p class="submit"><input type="submit" class="button" value="<?php esc_attr_e( 'Yes, Import!', 'forfragan' ); ?>" /></p>
			</form>
			<?php
		}

	}
}

function fm_ga_importer_init() {
    $GLOBALS['wp_import'] = new FM_Importer();
    register_importer('fm_ga', 
        __('Google Analytics', 'forfragan'), 
        __('Import google analytics data (.csv)', 'forfragan'), 
        array( $GLOBALS['wp_import'], 'dispatch' ) 
    );
}
add_action( 'admin_init', 'fm_ga_importer_init' );