WordPress script for doing a .csv export of misc data

bbg-csv-export.php

<?php

function bbg_csv_export() {
	if ( ! is_super_admin() ) {
		return;
	}

	if ( ! isset( $_GET['bbg_export'] ) ) {
		return;
	}

	$filename = 'mcnrc-members-' . time() . '.csv';

	$header_row = array(
		0 => 'Display Name',
		1 => 'Email',
		2 => 'Institution',
		3 => 'Registration Date',
	);

	$data_rows = array();

	global $wpdb, $bp;
	$users = $wpdb->get_results( "SELECT ID, user_email, user_registered FROM {$wpdb->users} WHERE user_status = 0" );

	foreach ( $users as $u ) {
		$row = array();
		$row[0] = bp_core_get_user_displayname( $u->ID );
		$row[1] = $u->user_email;
		$row[2] = xprofile_get_field_data( 2, $u->ID );
		$row[3] = $u->user_registered;

		$data_rows[] = $row;
	}

	$fh = @fopen( 'php://output', 'w' );

	fprintf( $fh, chr(0xEF) . chr(0xBB) . chr(0xBF) );

	header( 'Cache-Control: must-revalidate, post-check=0, pre-check=0' );
	header( 'Content-Description: File Transfer' );
	header( 'Content-type: text/csv' );
	header( "Content-Disposition: attachment; filename={$filename}" );
	header( 'Expires: 0' );
	header( 'Pragma: public' );

	fputcsv( $fh, $header_row );

	foreach ( $data_rows as $data_row ) {
		fputcsv( $fh, $data_row );
	}

	fclose( $fh );
	die();
}
add_action( 'admin_init', 'bbg_csv_export' );

how can i call this function inside wp?

Hi, this is a great snippet. I got it working on local server but on production server it gives me Header already send by output started on line 40. Havent you have same problem?

This is difficult to maintain. Can you please suggest dynamic way?

Fatal error: Uncaught TypeError: fputcsv(): Argument #2 ($fields) must be of type array, string given in