Restrict specific private page to a specific user

Question

Each user has a user meta called profile_url chosen during registration. After user creation, a page with that slug is created and made private (the author of the page is the admin). The user in his front-end dashboard has the possibility to make this page public or private. When the page is private, the owner user cannot see it.

I would like to make the private page visible to the owner user.

The only way that came to mind is to add capabilities, like:

$ user = new WP_User ($ user_id);
$ user-> add_cap ('read_private_pages');

but I'd like to specify the page id, and I don't know if it's possible.

Thank you

Answer 1

I assume you're using wp_insert_post() to create the private page for the user. The function returns the ID of the created page. You can use this ID as part of a custom capability you grant to the user.

// create the new $user

// create private page
$private_page_id = wp_insert_post( $postarr, $wp_error = false ); // returns id on success, 0 on failure
if ( $private_page_id ) {
  // grant custom cap
  $user->add_cap("can_access_{$private_page_id}", true);
}

When user tries to access the private page, use user_has_cap filter to check, if the user has the required custom cap and dynamically grant the private page reading capability.

add_filter('user_has_cap', 'user_can_access', 10, 4);
function user_can_access($allcaps, $caps, $args, $user) {
  $object = get_queried_object();
  // make sure we're on a post
  if ( ! is_a($object, 'WP_Post') ) {
    return $allcaps;
  }
  // it should be a private page post 
  if ( 'page' !== $object->post_type || 'private' !== $object->post_status ) {
    return $allcaps;
  }
  // does the user have the required access cap?
  $can_access = 'can_access_' . $object->ID;
  if ( isset( $allcaps[$can_access] ) && true === $allcaps[$can_access] ) {
    // if so, allow user to access the private content
    $allcaps['read_private_pages'] = true;
  }
  return $allcaps;
}

Answer 2

New answer

OK another way round would be to use WP_Query.

You could create a page called Profile and create a file called page-profile.php

Then use the code below to get the current users page data (assuming you are just saving the post name, not the complete user url in the meta)

// if user is not logged in then return or redirect to login page
if(!is_user_logged_in()) wp_safe_redirect(wp_login_url());

// get the user id
$user_id = get_current_user_id();

// get the current user profile url
$profile_url = get_user_meta($user_id, 'profile_url');

// page query args
$args = [
    'post_status' => ['publish','private'],
    'pagename' => $profile_url
];

// create the query
$page = new WP_Query( $args );

get_header();

?>

<?php if ( $page->have_posts() ): ?>

    <?php while($page->have_posts()): $page->the_post() ?>

        <?php the_title()?>

    <?php endwhile; ?>

<?php endif; ?>

<?php

get_footer();

This means the user would always got to the url http://yoursite.com/profile to view their page.

User pagename if page but use name if custom post type in the WP Query.