NGINX Unit

Universal Web App Server

NGINX Unit is a lightweight and versatile open-source server that has two primary capabilities:

• serves static media assets,
• runs application code in seven languages.

Unit compresses several layers of the modern application stack into a potent, coherent solution with a focus on performance, low latency, and scalability. It is intended as a universal building block for any web architecture regardless of its complexity, from enterprise-scale deployments to your pet's homepage.

Its native RESTful JSON API enables dynamic updates with zero interruptions and flexible configuration, while its out-of-the-box productivity reliably scales to production-grade workloads. We achieve that with a complex, asynchronous, multithreading architecture comprising multiple processes to ensure security and robustness while getting the most out of today's computing platforms.

Installation

macOS

Run the following command to install both unitd (the Unit daemon) and unitctl (the control tool).

$ brew install nginx/unit/unit

For details and available language packages, see the docs.

Docker

$ docker pull unit:<TAG>
$ mkdir /tmp/unit-control # customize as needed.
$ docker run -d \
      --mount type=bind,src=/tmp/unit-control,dst=/var/run \
      --mount type=bind,src=.,dst=/www \
      --network host \
      unit

For a description of image tags, see the docs.

WARNING: latest image tag may not provide support for specific language modules, do check the available image tags from the link above before pulling your image.

Your current working directory will now be mounted to the Unit image at /www. You can reach its socket at /tmp/unit-control/control.unit.sock assuming no further customizations have been made.

Debian, Ubuntu, Amazon Linux, Fedora, Red Hat

This helper script configures the correct package repositories for system.

$ wget https://raw.githubusercontent.com/nginx/unit/master/tools/setup-unit && chmod +x setup-unit
# ./setup-unit repo-config

Debian derivatives:

# apt install unit

Fedora derivatives:

# yum install unit

For details and available language packages, see the docs.

Getting Started with unitctl

unitctl streamlines the management of NGINX Unit processes through an easy-to-use command line interface. To get started with unitctl, download it from the official GitHub releases or Homebrew.

Installation

Note

If you installed Unit with Homebrew, you can skip this step as unitctl is included by default.

Download the appropriate unitctl binary for your system from the NGINX Unit releases.

$ tar xzvf unitctl-master-x86_64-unknown-linux-gnu.tar.gz
# mv unitctl /usr/local/bin/

Launch Unit using Docker

If you have Docker installed on your machine, and then you can effortlessly spin up one of Unit's official Docker images alongside your application.

Tip

How-to and configuration guides are available on unit.nginx.org for web application frameworks built with Python, PHP, WebAssembly, Node.js, Ruby, and more.

Here's an example using the unit:python Docker image:

$ unitctl instances new 127.0.0.1:8001 /path/to/app 'unit:python'

/path/to/app will mount to /www in the Docker filesystem.

Save this to /path/to/app/wsgi.py:

def application(environ, start_response):
    start_response("200 OK", [("Content-Type", "text/plain")])
    return (b"Hello, Python on Unit!")

You can then interactively edit the currently active configuration:

$ unitctl edit

{
  "listeners": {
    "*:8000": {
      // Point listener to new application
      "pass": "applications/python"
    }
  },

  // Add an application definition
  "applications": {
    "python": {
        "type": "python",
        "path": "/www/",
        "module": "wsgi"
    }
  }
}

Valid configurations will be applied upon save and close.

$ curl localhost:8000

Hello, Python on Unit!

More Python configuration examples can be found in the Unit docs.

Hello World with PHP and curl

Unit runs apps in a variety of languages. Let's explore the configuration of a simple PHP app on Unit with curl.

Suppose you saved a PHP script as /www/helloworld/index.php:

<?php echo "Hello, PHP on Unit!"; ?>

To run it on Unit with the unit-php module installed, first set up an application object. Let's store our first config snippet in a file called config.json:

{
    "helloworld": {
        "type": "php",
        "root": "/www/helloworld/"
    }
}

Saving it as a file isn't necessary, but can come in handy with larger objects.

Now, PUT it into the /config/applications section of Unit's control API, usually available by default via a Unix domain socket:

# curl -X PUT --data-binary @config.json --unix-socket  \
       /path/to/control.unit.sock http://localhost/config/applications

{
	"success": "Reconfiguration done."
}

Next, reference the app from a listener object in the /config/listeners section of the API. This time, we pass the config snippet straight from the command line:

# curl -X PUT -d '{"127.0.0.1:8080": {"pass": "applications/helloworld"}}'  \
       --unix-socket /path/to/control.unit.sock http://localhost/config/listeners

{
    "success": "Reconfiguration done."
}

Now Unit accepts requests at the specified IP and port, passing them to the application process. Your app works!

$ curl 127.0.0.1:8080

      Hello, PHP on Unit!

Finally, query the entire /config section of the control API:

# curl --unix-socket /path/to/control.unit.sock http://localhost/config/

Unit's output should contain both snippets, neatly organized:

{
    "listeners": {
        "127.0.0.1:8080": {
            "pass": "applications/helloworld"
        }
    },

    "applications": {
        "helloworld": {
            "type": "php",
            "root": "/www/helloworld/"
        }
    }
}

WebAssembly

Unit supports running WebAssembly Components (WASI 0.2). For more information see the Unit Configuration Docs.

OpenAPI Specification

Our OpenAPI specification aims to simplify configuring and integrating NGINX Unit deployments and provide an authoritative source of knowledge about the control API.

Community

• The go-to place to start asking questions and share your thoughts is GitHub Discussions.

• Our GitHub issues page offers space for a more technical discussion at your own pace.

• The project map on GitHub sheds some light on our current work and plans for the future.

• Our official website may provide answers not easily found otherwise.

• Get involved with the project by contributing! See the contributing guide for details.

• To reach the team directly, subscribe to the mailing list.

• For security issues, email us, mentioning NGINX Unit in the subject and following the CVSS v3.1 spec.