How to use WordPress Rewrite API?

Complete tutorial – Coming Soon

function custom_rewrite_basic() {
	add_rewrite_rule('^products/([^/]*)/reviews/([^/]*)', 'index.php?product-slug=$matches[1]&product-child=reviews&product-comment-key=$matches[2]', 'top');
	}
	add_action('init', 'custom_rewrite_basic');

	function prefix_register_query_var( $vars ) {
	$vars[] = 'product-slug';
	$vars[] = 'product-child';
	$vars[] = 'product-comment-key';
	return $vars;
	}

	add_filter( 'query_vars', 'prefix_register_query_var' );

	function prefix_url_rewrite_templates() {

	if ( get_query_var( 'product-slug' ) && get_query_var( 'product-child' ) == 'reviews' && get_query_var( 'product-comment-key' )) {

	$product_slug = get_query_var( 'product-slug' );
	$product_page = get_page_by_path($product_slug, OBJECT, 'product' );
	$product_id = $product_page->ID;

	$product_comment_key = get_query_var( 'product-comment-key' );
	$product_comment_meta = explode('-', $product_comment_key);
	$comment_id = end($product_comment_meta);

	$comment_data = get_comment( $comment_id);
	$comment_status = wp_get_comment_status($comment_id);
	if ($comment_status == 'approved'):

	$other_comments = array();
	$other_comments = get_comments(array(
	'post_id'=> $product_page->ID,
	'number' => '',
	'status' => 'approve',
	'orderby' => 'rand'
	));
	shuffle($other_comments);
	$GLOBALS['comments'] = $other_comments;

	$other_comment_data = $other_comments[0];
	$other_comment_id = $other_comment_data->comment_ID;
	$other_comment = get_comment($other_comment_id, OBJECT);
	$comment_content = strip_tags($comment_data->comment_content . $comment->comment_content);

	if (count($comment_count) < 160){ $comment_content.= ' ' . $other_comment->comment_content;
	}

	$comment_content = strip_tags($comment_content);
	$comment_content = substr($comment_content,0,155);

	if (count($comment_content) < 160){ $other_comment_data = $other_comments[1]; $other_comment_id = $other_comment_data->comment_ID;
	$other_comment = get_comment($other_comment_id, OBJECT);
	$comment_content.= ' ' . $other_comment->comment_content;
	}

	$comment_content = strip_tags($comment_content);
	$comment_content = substr($comment_content,0,155);

	$GLOBALS['seo_title'] = $product_page->post_title . ' - Review #' . $comment_id . ' By ' . $comment_data->comment_author;
	$GLOBALS['seo_description'] = substr($comment_data->comment_content,0,155);
	$GLOBALS['seo_keyword'] = $product_page->post_title . ' - Review #' . $comment_id;
	$GLOBALS['current_url'] = get_permalink($product_id) . 'reviews/' . get_query_var( 'product-comment-key' );
	$GLOBALS['seo_image'] = get_the_post_thumbnail_url($product_id,'full');;

	add_filter('wpseo_title', function($seo_title){
	return $GLOBALS['seo_title'];
	},100);

	add_filter('wpseo_metadesc', function($seo_title){
	return $GLOBALS['seo_description'];
	},100);

	add_filter('wpseo_metakey', function($seo_title){
	return $GLOBALS['seo_keyword'];
	},100);

	add_filter('wpseo_opengraph_url', function($seo_title){
	return $GLOBALS['current_url'];
	},100);

	add_filter('wpseo_opengraph_image',function(){
	return $GLOBALS['seo_image'] ;
	},100);

	add_filter('wpseo_twitter_image',function(){
	return $GLOBALS['seo_image'] ;
	},100);

	add_filter( 'template_include', function() {
	return get_template_directory() . '/page-templates/page-product-comments-single.php';
	});

	else:
	add_filter( 'template_include', function() {
	return get_template_directory() . '/404.php';
	});
	endif;
	}
}

add_action( 'template_redirect', 'prefix_url_rewrite_templates' );