MyShaarli/application/ApplicationUtils.php
ArthurHoaro bfe4f536bb Add a version hash for asset loading to prevent browser's cache issue
The hash is generated using the same salt as the one used for credentials (1 salt per instance)  in order to avoid exposing the instance version.

Fixes #965
2017-10-01 11:10:37 +02:00

238 lines
8.2 KiB
PHP

<?php
/**
* Shaarli (application) utilities
*/
class ApplicationUtils
{
/**
* @var string File containing the current version
*/
public static $VERSION_FILE = 'shaarli_version.php';
private static $GIT_URL = 'https://raw.githubusercontent.com/shaarli/Shaarli';
private static $GIT_BRANCHES = array('latest', 'stable');
private static $VERSION_START_TAG = '<?php /* ';
private static $VERSION_END_TAG = ' */ ?>';
/**
* Gets the latest version code from the Git repository
*
* The code is read from the raw content of the version file on the Git server.
*
* @param string $url URL to reach to get the latest version.
* @param int $timeout Timeout to check the URL (in seconds).
*
* @return mixed the version code from the repository if available, else 'false'
*/
public static function getLatestGitVersionCode($url, $timeout=2)
{
list($headers, $data) = get_http_response($url, $timeout);
if (strpos($headers[0], '200 OK') === false) {
error_log('Failed to retrieve ' . $url);
return false;
}
return $data;
}
/**
* Retrieve the version from a remote URL or a file.
*
* @param string $remote URL or file to fetch.
* @param int $timeout For URLs fetching.
*
* @return bool|string The version or false if it couldn't be retrieved.
*/
public static function getVersion($remote, $timeout = 2)
{
if (startsWith($remote, 'http')) {
if (($data = static::getLatestGitVersionCode($remote, $timeout)) === false) {
return false;
}
} else {
if (! is_file($remote)) {
return false;
}
$data = file_get_contents($remote);
}
return str_replace(
array(self::$VERSION_START_TAG, self::$VERSION_END_TAG, PHP_EOL),
array('', '', ''),
$data
);
}
/**
* Checks if a new Shaarli version has been published on the Git repository
*
* Updates checks are run periodically, according to the following criteria:
* - the update checks are enabled (install, global config);
* - the user is logged in (or this is an open instance);
* - the last check is older than a given interval;
* - the check is non-blocking if the HTTPS connection to Git fails;
* - in case of failure, the update file's modification date is updated,
* to avoid intempestive connection attempts.
*
* @param string $currentVersion the current version code
* @param string $updateFile the file where to store the latest version code
* @param int $checkInterval the minimum interval between update checks (in seconds
* @param bool $enableCheck whether to check for new versions
* @param bool $isLoggedIn whether the user is logged in
* @param string $branch check update for the given branch
*
* @throws Exception an invalid branch has been set for update checks
*
* @return mixed the new version code if available and greater, else 'false'
*/
public static function checkUpdate($currentVersion,
$updateFile,
$checkInterval,
$enableCheck,
$isLoggedIn,
$branch='stable')
{
// Do not check versions for visitors
// Do not check if the user doesn't want to
// Do not check with dev version
if (! $isLoggedIn || empty($enableCheck) || $currentVersion === 'dev') {
return false;
}
if (is_file($updateFile) && (filemtime($updateFile) > time() - $checkInterval)) {
// Shaarli has checked for updates recently - skip HTTP query
$latestKnownVersion = file_get_contents($updateFile);
if (version_compare($latestKnownVersion, $currentVersion) == 1) {
return $latestKnownVersion;
}
return false;
}
if (! in_array($branch, self::$GIT_BRANCHES)) {
throw new Exception(
'Invalid branch selected for updates: "' . $branch . '"'
);
}
// Late Static Binding allows overriding within tests
// See http://php.net/manual/en/language.oop5.late-static-bindings.php
$latestVersion = static::getVersion(
self::$GIT_URL . '/' . $branch . '/' . self::$VERSION_FILE
);
if (! $latestVersion) {
// Only update the file's modification date
file_put_contents($updateFile, $currentVersion);
return false;
}
// Update the file's content and modification date
file_put_contents($updateFile, $latestVersion);
if (version_compare($latestVersion, $currentVersion) == 1) {
return $latestVersion;
}
return false;
}
/**
* Checks the PHP version to ensure Shaarli can run
*
* @param string $minVersion minimum PHP required version
* @param string $curVersion current PHP version (use PHP_VERSION)
*
* @throws Exception the PHP version is not supported
*/
public static function checkPHPVersion($minVersion, $curVersion)
{
if (version_compare($curVersion, $minVersion) < 0) {
throw new Exception(
'Your PHP version is obsolete!'
.' Shaarli requires at least PHP '.$minVersion.', and thus cannot run.'
.' Your PHP version has known security vulnerabilities and should be'
.' updated as soon as possible.'
);
}
}
/**
* Checks Shaarli has the proper access permissions to its resources
*
* @param ConfigManager $conf Configuration Manager instance.
*
* @return array A list of the detected configuration issues
*/
public static function checkResourcePermissions($conf)
{
$errors = array();
// Check script and template directories are readable
foreach (array(
'application',
'inc',
'plugins',
$conf->get('resource.raintpl_tpl'),
$conf->get('resource.raintpl_tpl').'/'.$conf->get('resource.theme'),
) as $path) {
if (! is_readable(realpath($path))) {
$errors[] = '"'.$path.'" directory is not readable';
}
}
// Check cache and data directories are readable and writable
foreach (array(
$conf->get('resource.thumbnails_cache'),
$conf->get('resource.data_dir'),
$conf->get('resource.page_cache'),
$conf->get('resource.raintpl_tmp'),
) as $path) {
if (! is_readable(realpath($path))) {
$errors[] = '"'.$path.'" directory is not readable';
}
if (! is_writable(realpath($path))) {
$errors[] = '"'.$path.'" directory is not writable';
}
}
// Check configuration files are readable and writable
foreach (array(
$conf->getConfigFileExt(),
$conf->get('resource.datastore'),
$conf->get('resource.ban_file'),
$conf->get('resource.log'),
$conf->get('resource.update_check'),
) as $path) {
if (! is_file(realpath($path))) {
# the file may not exist yet
continue;
}
if (! is_readable(realpath($path))) {
$errors[] = '"'.$path.'" file is not readable';
}
if (! is_writable(realpath($path))) {
$errors[] = '"'.$path.'" file is not writable';
}
}
return $errors;
}
/**
* Returns a salted hash representing the current Shaarli version.
*
* Useful for assets browser cache.
*
* @param string $currentVersion of Shaarli
* @param string $salt User personal salt, also used for the authentication
*
* @return string version hash
*/
public static function getVersionHash($currentVersion, $salt)
{
return hash_hmac('sha256', $currentVersion, $salt);
}
}