command.php

/**
 * Converts single-key metadata into multiple keys.
 *
 * @when before_wp_load
 */
$datagram_convert = function() {
	
	$datagrams		= WP_CLI::runcommand(
		'post list --post_type=datagram --format=json',
		[
		  'return'     => true,  // Return 'STDOUT'; use 'all' for full object.
		  'parse'      => 'json', // Parse captured STDOUT to JSON array.
		  'launch'     => false, // Reuse the current process.
		  'exit_error' => true,  // Halt script execution on error.
		]
	);
	WP_CLI::success( $datagrams );
};
WP_CLI::add_command( 'datagram-convert', $datagram_convert );