When migrating from basecamp classic to the new basecamp project IDs change. This quick & dirty script will identify projects by name and update the project IDs in your database.

update_bc_project_ids.php

<?php

ob_start();

//
// Config
// 

// Old Basecamp
$bc_old = array(
	'address' => 'https://XXXXXX.basecamphq.com/projects.xml',
	'username' => 'user_api_token',
	'password' => 'X',
	'format' => 'xml'
);

// New Basecamp
$bc_new = array(
	'address' => 'https://basecamp.com/XXXXXX/api/v1/projects.json',
	'username' => '',
	'password' => '',
	'format' => 'json'
 );

// database
$host = 'localhost';
$database = '';
$user = '';
$pass = '';

mysql_connect( $host, $user, $pass ) or die( 'Count not connect: ' . mysql_error() );
mysql_select_db( $database ) or die( "Could not select database: " . mysql_error() );


//
// Make update
//

function get_data( $instance ) {
	$ch = curl_init();
	curl_setopt( $ch, CURLOPT_URL, $instance['address'] );
	curl_setopt( $ch, CURLOPT_TIMEOUT, 30 );
	curl_setopt( $ch, CURLOPT_RETURNTRANSFER, 1);
	curl_setopt( $ch, CURLOPT_USERAGENT, 'Migrate Project IDs (http://gradybritton.com)' );
	curl_setopt( $ch, CURLOPT_USERPWD, $instance['username'] . ':' . $instance['password'] );
	curl_setopt( $ch, CURLOPT_FOLLOWLOCATION, 1);
	curl_setopt( $ch, CURLOPT_UNRESTRICTED_AUTH, 1);
	$info = curl_getinfo( $ch );
	$data = curl_exec( $ch );
	curl_close($ch);
	$data = ( $instance['format'] == 'xml' ? new SimpleXMLElement( $data ) : json_decode( $data ) ); // convert xml/json to php array or object
	return $data;
}

// old project ids
echo '<p>Getting projects from basecamp classic&hellip; '; ob_flush(); flush();
$old = get_data($bc_old);
foreach ( $old->project as $k => $v) {
	$old_projects[] = array(
		'name' => (string)$v->name,
		'id' => (string)$v->id
	);
}
sort($old_projects);
echo '<span style="color:#0a0">Success!</span></p>'; ob_flush(); flush();

// new project ids
echo '<p>Getting projects from new basecamp&hellip; '; ob_flush(); flush();
$new = get_data($bc_new);
foreach ( $new as $k => $v) {
	$new_projects[] = array(
		'name' => str_replace(': ','',strstr($v->name,':')), // new basecamp prefixes company names to migrated projects. strip company name
		'id' => $v->id
	);
}
sort($new_projects);
echo '<span style="color:#0a0">Success!</span></p>'; ob_flush(); flush();

// loop through projects comparing by project name to u
foreach( $old_projects as $old ) {
	$old_name = $old['name'];
	$old_id = $old['id'];

	foreach( $new_projects as $new) {
		$new_name = $new['name'];
		$new_id = $new['id'];
		if ($old_name === $new_name) {

			echo '<p>Updating ' .$old_name . ' (' . $old_id . ') &rarr; ' . $new_name . ' (' . $new_id . ')&hellip; '; ob_flush(); flush();

			$u = mysql_query("UPDATE projects SET id = '$new_id' WHERE project_id = '$old_id'") or die(mysql_error());
			echo ( $u ? '<span style="color:#0a0;">Success!</span>':'<span style="color:#a00;">Failed</span>') . '</p>'; ob_flush(); flush();
		}
	}
}

// done!
die( '<p style="font-weight: bold;">Done!</p>' );