Path Hasher

Description

Path Hasher is a PHP library for deterministically serializing and hashing filesystem objects (files, directories, and symlinks) using the NAR (Nix ARchive) format designed by Eelco Dolstra for the Nix ecosystem.

This library enables you to:

• Serialize any filesystem path into the NAR format, ensuring consistent and reproducible results across platforms.
• Compute cryptographic hashes of paths in multiple encodings (hex, SRI, Nix base32), matching the output of the nix hash path <path> command.
• Extract or reconstruct filesystem trees from NAR archives.

See chapter 5 of Eelco Dolstra’s PhD thesis for technical details about the NAR format.

Installation

composer require loophp/path-hasher

Usage

Basic Example

<?php

use Loophp\PathHasher\NAR;

$path = '/path/to/your/file_or_directory';

$hash = (new NAR())->hash($path);

echo $hash; // Outputs the SRI hash (e.g., sha256-<base64>)

The equivalent CLI command is:

nix hash path /path/to/your/file_or_directory

The two outputs will match.

To generate a NAR archive from a given path:

<?php

use Loophp\PathHasher\NAR;

$nar = new NAR();

$handle = fopen('vendor.nar', 'w');
foreach ($nar->stream('./vendor') as $chunk) {
    fwrite($handle, $chunk);
}
fclose($handle);

Methods available are:

• hash: Compute the SRI hash of a given path.
• extract: Extract a NAR archive to a specified directory.
• stream: Get a stream generator of the NAR archive.
• computeHashes: Compute hashes of the NAR archive with different algorithms.

Code quality, tests, benchmarks

Every time changes are introduced into the library, Github runs the tests.

The library has tests written with PHPUnit. Feel free to check them out in the tests directory.

Before each commit, some inspections are executed with GrumPHP; run composer grumphp to check manually.

Contributing

Feel free to contribute by sending pull requests. We are a usually very responsive team and we will help you going through your pull request from the beginning to the end.

For some reasons, if you can't contribute to the code and willing to help, sponsoring is a good, sound and safe way to show us some gratitude for the hours we invested in this package.

Sponsor me on Github and/or any of the contributors.