Download all your file from Basecamp Classic

basecamp-classic-files.php

<?php
define('BASE', './basecamp'); // Folder to store files (must be writable)
define('BASECAMP_URL', '[YOUR BASECAMP URL HERE]'); // e.g. https://stelabouras.basecamphq.com/ (Don't forget the trailing slash!)
define('BASECAMP_KEY', '[YOUR API KEY HERE]'); // e.g. one huge string (found in 'My info' in the Authentication tokens section)

define('COOKIE', tempnam(sys_get_temp_dir(), uniqid()));

function curl($url, $prefix = true)
{
    $url = ($prefix ? BASECAMP_URL : '').$url;

    $curl = curl_init();

    curl_setopt($curl, CURLOPT_HTTPAUTH, CURLAUTH_BASIC);
    curl_setopt($curl, CURLOPT_HTTPGET, true);
    curl_setopt($curl, CURLOPT_HEADER, false);
    curl_setopt($curl, CURLOPT_FOLLOWLOCATION, true);

    if ($prefix) {
        curl_setopt($curl, CURLOPT_HTTPHEADER, ['Accept: application/xml', 'Content-Type: application/xml']);
    }

    curl_setopt($curl, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($curl, CURLOPT_USERPWD, BASECAMP_API.':X');
    curl_setopt($curl, CURLOPT_SSL_VERIFYPEER, false);
    curl_setopt($curl, CURLOPT_COOKIESESSION, true);
    curl_setopt($curl, CURLOPT_COOKIEJAR, COOKIE);
    curl_setopt($curl, CURLOPT_COOKIEFILE, COOKIE);
    curl_setopt($curl, CURLOPT_AUTOREFERER, true);
    curl_setopt($curl, CURLOPT_REFERER, $url);

    echo "Downloading {$url}\n";

    curl_setopt($curl, CURLOPT_URL, $url);

    $response = curl_exec($curl);

    return $prefix ? simplexml_load_string($response) : $response;
}

function remote($project, array $file, array $files)
{
    $location = BASE.'/'.$project->name.'/'.$file['filename'];

    if (in_array($file['filename'], $files)) {
        $location .= '-'.uniqid(rand());
    }

    if (!empty($file['extension'])) {
        $location .= '.'.$file['extension'];
    }

    return $location;
}

$projects = curl('projects.xml');
$projectsTotal = count($projects);
$projectsCounter = 0;

foreach ($projects->project as $project) {
    echo "\nSaving attachments for project {$project->name} (".(++$projectsCounter)."/{$projectsTotal})\n";

    if (!is_dir(BASE.'/'.$project->name)) {
        mkdir(BASE.'/'.$project->name, 0755, true);
    }

    $files = array();
    $page = 0;

    do {
        $attachments = curl('projects/'.$project->id.'/attachments.xml?n='.$page);

        if (empty($attachments->attachment)) {
            continue;
        }

        $attachmentsTotal = count($attachments->attachment);
        $attachmentsCounter = 0;
        $page += 100;

        foreach ($attachments->attachment as $attachment) {
            $file = pathinfo($attachment->name);
            $storage = remote($project, $file, $files);

            if (is_file($storage)) {
                echo "Already downloaded file {$attachment->name} on {$storage} (".(++$attachmentsCounter)."/{$attachmentsTotal})\n";
                continue;
            }

            file_put_contents($storage, curl($attachment->{'download-url'}, false));

            $files[] = $file['filename'];

            echo "Saving file {$attachment->name} on {$storage} (".(++$attachmentsCounter)."/{$attachmentsTotal})\n";
        }
    } while (count($attachments->attachment) === 100);
}