Jinja PHP

A minimalistic zero-dependency PHP implementation of the Jinja templating engine, specifically designed for parsing and rendering machine learning (ML) chat templates. This project is heavily inspired by HuggingFace's Jinja template engine in JavaScript, intended primarily for ML chat templates, but is versatile enough to be used for general purposes of parsing most Jinja templates.

Installation

Install Jinja PHP through Composer:

composer require codewithkyrian/jinja-php

Usage

Here’s how you can use Jinja PHP to render a template:

$sourceString = "{{ bos_token }}{% for message in messages %}{% if (message['role'] == 'user') != (loop.index0 % 2 == 0) %}{{ raise_exception('Conversation roles must alternate user/assistant/user/assistant/...') }}{% endif %}{% if message['role'] == 'user' %}{{ '[INST] ' + message['content'] + ' [/INST]' }}{% elif message['role'] == 'assistant' %}{{ message['content'] + eos_token + ' ' }}{% else %}{{ raise_exception('Only user and assistant roles are supported!') }}{% endif %}{% endfor %}";
$args = [
    'messages' => [
        ['role' => 'user', 'content' => 'Hello!'],
        ['role' => 'assistant', 'content' => 'Hi! How are you?'],
        ['role' => 'user', 'content' => 'I am doing great.'],
        ['role' => 'assistant', 'content' => 'That is great to hear.'],
    ],
    "add_generation_prompt" => true,
    "bos_token" => "<s>",
    "eos_token" => "</s>",
    "unk_token" => "<unk>",
];

$template = new Template($sourceString);

$rendered = $template->render($args);
// <s>[INST] Hello! [/INST]Hi! How are you?</s> [INST] I am doing great. [/INST]That is great to hear.</s> 

Advanced Usage

Jinja PHP supports various control structures from Jinja templates. Here are some examples:

Conditional Statements:

{% if user.isActive %}
  "Hello," {{ user.name }}!
{% else %}
  "Hello, Guest!"
{% endif %}

For Loops

<ul>
{% for user in users %}
  <li>{{ user.name }}</li>
{% else %}
  <li>No users found.</li>
{% endfor %}
</ul>

{% for user in users %}
  {{ loop.index }} - {{ user.name }}
{% endfor %}

Variable Filters

{{ "Hello World!"|lower }}

Comprehensive Feature Support

Jinja PHP is designed to be robust and feature-rich, offering support for a wide range of functionalities beyond the basics of templating. This includes handling exceptions, using default string methods like strip() or upper(), working with dictionaries, and much more. If there's a feature you need that isn't currently implemented in Jinja PHP, we encourage you to request it. Additionally, if you're proficient with PHP and understand the internals of templating engines, consider contributing to the project by submitting a pull request with your proposed feature.

Testing

Jinja PHP comes with a suite of tests to ensure functionality remains consistent and reliable. To run the tests:

composer test

Contributors

• Kyrian Obikwelu
• Other contributors are welcome.

Acknowledgements

• Hugging Face for their work on ML chat templates.
• The Jinja template engine for Python, which served as the primary inspiration for this project.

Support

If you find any issues or have a question, feel free to open an issue in the repo.

License

This project is licensed under the MIT License. See the LICENSE file for more information.