A simple Pico plugin to create redirection pages to arbitrary URLs.

PicoRedirect.php

<?php

/**
 * Pico redirect plugin
 *
 * Adds a `Redirect` meta header to redirect to other URLs. The meta header
 * supports URL substitution variables, namely %base_url%, %plugins_url%,
 * %themes_url%, %assets_url% and %theme_url%.
 *
 * Example:
 *
 * ```markdown
 * ---
 * Redirect: %base_url%?sub/page
 * ---
 * ```
 *
 * This plugin requires Pico 2.1+ and PHP 7.2.
 *
 * @author  Daniel Rudolf
 * @link    http://picocms.org
 * @license http://opensource.org/licenses/MIT The MIT License
 * @version 0.0.1
 */
class PicoRedirect extends AbstractPicoPlugin
{
    const API_VERSION = 3;

    public function onMetaHeaders(array &$headers)
    {
        $headers['Redirect'] = 'redirect';
    }

    public function onMetaParsed(array &$meta)
    {
        if ($meta['redirect']) {
            $redirectUrl = $this->getPico()->substituteUrl($meta['redirect']);
            $redirectUrl = $this->getPico()->getAbsoluteUrl($redirectUrl, null, false);

            $serverProtocol = $_SERVER['SERVER_PROTOCOL'] ?? 'HTTP/1.1';
            header($serverProtocol . ' 302 Found');
            header('Location: ' . $redirectUrl);
            exit();
        }
    }
}

@notakoder You can add hidden: true to your page's YAML Frontmatter. However, not all themes respect this header, but adding support for it is pretty easy ({% if not page.hidden %}).

Oh my theme already has that condition. In fact it was because of this condition, I searched the doc on hiding the page and came across the _ hiding method. Didn't know that it can be done using YAML frontmatter too. Thank you.