##filehashDB##

filehashDB stores file hashes that can be checked at a later time to see if they have changed. This can be used, for example, to automatically re-compress CSS or javascript files on a website. See "Hashing Method" below.

By default, filehashDB uses INI files to store the file hashes. To use XML files, change HashDBIni to HashDBXml in filehashDB.php.

###Usage###

####Using filehashDB##### Before using, make sure you have run $ chmod +x filehashDB.php.
The database file will be created automatically when filehashDB is run.

Usage is fairly simple. Execute the following:
    $ filehashDB.php [filename]
and it will add the current file hash.

The exit code will be 0 if the hash was unchanged, and 1 if the hash was different than the previously stored hash (or did not exist in the database).

####Hashing Method####

By default, filehashDB uses SHA1 to hash files. MD5 can be implemented with minor code changes for a ~50% speed increase.
In filehashDB.php, change the new FileHashSHA(... line to new FileHashMD5(....

####Storage#### The BaseHashDB class should be extended to implement a specific storage engine. By default, filehashDB includes INI and XML storage engines.

####Using the filehashDB classes####

By default, filehashDB uses ini files to store the file hash information. To implement a different method of storage, override the BaseHashDB class.

• To use the INI storage engine, use the HashDBIni class.
• To use the XML storage engine, use the HashDBXml class.

###Classes###

• FileHash - Abstract class that calculates the hash for a file.
• FileHashMD5 - MD5 hash implementation.
• FileHashSHA1 - SHA1 hash implementation.
• BaseHashDB - Base Database class, to be extended by child classes that implement various storage engines.
• HashDBIni - Database class, handling loading, saving, and comparing of hashes using ini files.
• HashDBXml - Database class, handling loading, saving, and comparing of hashes using XML files.

####Implementing filehashDB####

To implement filehashDB in a PHP project, use code similar to the following:

include('filehashDB/autoload.php');

$filename = "file-to-hash.txt";
$db = new HashDBXml("db.xml");
$db->load();

$fh = new FileHashSHA1($filename);
$compareHash = $db->compareHash($fh);

echo ($compareHash ? 'unchanged' : 'changed') . PHP_EOL;
if (!$compareHash)
  $db->setHash($fh);

$db->save();

###License### filehashDB is available under the MIT License.