Restirct WordPress post or page to logged in users

post-page-user-log-in-required-twentynineteen

<?php
/**
 * Single post and page template for restricting the title and content unless the user is logged in
 * Sources: 
 * https://www.wpbeginner.com/wp-themes/create-custom-single-post-templates-for-specific-posts-or-sections-in-wordpress/
 * https://codex.wordpress.org/Conditional_Tags
 *
 * @link https://developer.wordpress.org/themes/basics/template-hierarchy/#single-post
 *
 * @package WordPress
 * @subpackage Twenty_Nineteen
 * @since 1.0.0
 *
 * License: GPL 2 or later
 *
 * Template Name: Log in Required
 * Template Post Type: post, page
 *
 */

get_header();
?>

	<div id="primary" class="content-area">
		<main id="main" class="site-main">

<?php
	if ( is_user_logged_in() ) {  // check if user is logged in

/* * 
 * Start the Loop 
 * This example  uses TwentyNineteen for the loop, if using a different theme subsitute that loop here.
 * */
		while ( have_posts() ) :
			the_post();

			get_template_part( 'template-parts/content/content', 'single' );

			if ( is_singular( 'attachment' ) ) {
				// Parent post navigation.
				the_post_navigation(
					array(
						/* translators: %s: parent post link */
						'prev_text' => sprintf( __( '<span class="meta-nav">Published in</span><span class="post-title">%s</span>', 'twentynineteen' ), '%title' ),
					)
				);
			} elseif ( is_singular( 'post' ) ) {
				// Previous/next post navigation.
				the_post_navigation(
					array(
						'next_text' => '<span class="meta-nav" aria-hidden="true">' . __( 'Next Post', 'twentynineteen' ) . '</span> ' .
							'<span class="screen-reader-text">' . __( 'Next post:', 'twentynineteen' ) . '</span> <br/>' .
							'<span class="post-title">%title</span>',
						'prev_text' => '<span class="meta-nav" aria-hidden="true">' . __( 'Previous Post', 'twentynineteen' ) . '</span> ' .
							'<span class="screen-reader-text">' . __( 'Previous post:', 'twentynineteen' ) . '</span> <br/>' .
							'<span class="post-title">%title</span>',
					)
				);
			}

			// If comments are open or we have at least one comment, load up the comment template.
			if ( comments_open() || get_comments_number() ) {
				comments_template();
			}

		endwhile; // End of the TwentyNineteen  loop.
    
	} else { // If not logged in present a link to log into the site
		echo '<p style="text-align: center;"><a href="' .  wp_login_url( get_permalink() ) . '" title="Login">Log in to view this post</a></p>';
	}
		?>

		</main><!-- #main -->
	</div><!-- #primary -->

<?php
get_footer();

post-page-user-log-in-required.php

<?php
/**
 * Single post and page template for restricting the title and content unless the user is logged in
 * Sources: 
 * https://www.wpbeginner.com/wp-themes/create-custom-single-post-templates-for-specific-posts-or-sections-in-wordpress/
 * https://codex.wordpress.org/Conditional_Tags
 *
 * @link https://developer.wordpress.org/themes/basics/template-hierarchy/#single-post
 *
 * License: GPL 2 or later
 *
 * Template Name: Log in Required
 * Template Post Type: post, page
 *
 */

get_header();
?>

	<div id="primary" class="content-area">
		<main id="main" class="site-main">

<?php
	if ( is_user_logged_in() ) {  // check if user is logged in

    // You will want to edit the following loop to match your child theme design for single.php ando page.php etc.
    while ( have_posts() ) :
			the_post();

			the_title();
		
			the_content();

			// If comments are open or we have at least one comment, load up the comment template.
			if ( comments_open() || get_comments_number() ) :
				comments_template();
			endif;

			endwhile; // End of the loop.
    
	} else { // If not logged in present a link to log into the site
		echo '<p style="text-align: center;"><a href="' .  wp_login_url( get_permalink() ) . '" title="Login">Log in to view this post</a></p>';
	}
		?>

		</main><!-- #main -->
	</div><!-- #primary -->

<?php
get_footer();