Lightbug

🐝 A Mojo HTTP framework with wings 🔥

Overview

Lightbug is a simple and sweet HTTP framework for Mojo that builds on best practice from systems programming, such as the Golang FastHTTP and Rust may_minihttp.

This is not production ready yet. We're aiming to keep up with new developments in Mojo, but it might take some time to get to a point when this is safe to use in real-world applications.

Lightbug currently has the following features:

• Pure Mojo networking! No dependencies on Python by default
• TCP-based server and client implementation
• Assign your own custom handler to a route
• Craft HTTP requests and responses with built-in primitives
• Everything is fully typed, with no def functions used

We're working on support for the following (contributors welcome!):

• SSL/HTTPS support
• UDP support
• Better error handling, improved form/multipart and JSON support
• Multiple simultaneous connections, parallelization and performance optimizations
• WebSockets, HTTP 2.0/3.0 support
• ASGI spec conformance

The test coverage is also something we're working on.

The plan is to get to a feature set similar to Python frameworks like Starlette, but with better performance.

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Getting Started

The only hard dependencies for lightbug_http are Mojo and Git. Learn how to get up and running with Mojo on the Modular website. The Docker installation was removed with the changes in Modular CLI. It will be available once Modular provides needed functionality for Docker setups.

Once you have Mojo set up locally,

1. Clone the repo

   git clone https://github.com/saviorand/lightbug_http.git

2. Switch to the project directory:

   cd lightbug_http

   then run:

   mojo lightbug.🔥

   Open localhost:8080 in your browser. You should see a welcome screen.

   Congrats 🥳 You're using Lightbug!

3. Add your handler in lightbug.🔥 by passing a struct that satisfies the following trait:

   trait HTTPService:
    fn func(self, req: HTTPRequest) raises -> HTTPResponse:
        ...

   For example, to make a Printer service that simply prints the request to console:

   @value
   struct Printer(HTTPService):
      fn func(self, req: HTTPRequest) raises -> HTTPResponse:
         var body = req.body_raw
         print(String(body))
   
         return OK(body)

   Routing is not in scope for this library, but you can easily set up routes yourself:

   @value
   struct ExampleRouter(HTTPService):
      fn func(self, req: HTTPRequest) raises -> HTTPResponse:
         var body = req.body_raw
         var uri = req.uri()
   
         if uri.path() == "/":
               print("I'm on the index path!")
         if uri.path() == "/first":
               print("I'm on /first!")
         elif uri.path() == "/second":
               print("I'm on /second!")
         elif uri.path() == "/echo":
               print(String(body))
   
         return OK(body)

   We plan to add routing in a future library called lightbug_api, see Roadmap for more details.

4. Run mojo lightbug.🔥. This will start up a server listening on localhost:8080. Or, if you prefer to import the server into your own app:

   from lightbug_http.sys.server import SysServer
   from lightbug_http.service import Printer
   
   
   fn main() raises:
      var server = SysServer()
      var handler = Printer()
      server.listen_and_serve("0.0.0.0:8080", handler)

   Feel free to change the settings in listen_and_serve() to serve on a particular host and port.

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Serving static files

The default welcome screen shows an example of how to serve files like images or HTML using Lightbug. Mojo has built-in open, read and read_bytes methods that you can use to read files from e.g. a static directory and serve them on a route:

@value
struct Welcome(HTTPService):
    fn func(self, req: HTTPRequest) raises -> HTTPResponse:
        var uri = req.uri()

        if uri.path() == "/":
            var html: Bytes
            with open("static/lightbug_welcome.html", "r") as f:
                html = f.read_bytes()
            return OK(html, "text/html; charset=utf-8")
        
        if uri.path() == "/logo.png":
            var image: Bytes
            with open("static/logo.png", "r") as f:
                image = f.read_bytes()
            return OK(image, "image/png")
        
        return NotFound(uri.path())

Using the client

Create a file, e.g client.mojo with the following code. Run mojo client.mojo to execute the request to a given URL.

fn test_request(inout client: MojoClient) raises -> None:
    var uri = URI("http://httpbin.org/status/404")
    var request = HTTPRequest(uri)
    var response = client.do(request)

    # print status code
    print("Response:", response.header.status_code())

    # print raw headers
    # print("Headers:", response.header.headers())

    # print parsed headers (only some are parsed for now)
    print("Content-Type:", String(response.header.content_type()))
    print("Content-Length", response.header.content_length())
    print("Connection:", response.header.connection_close())
    print("Server:", String(response.header.server()))

    # print body
    print(String(response.get_body()))

Pure Mojo-based client is available by default. This client is also used internally for testing the server.

Switching between pure Mojo and Python implementations

By default, Lightbug uses the pure Mojo implementation for networking. To use Python's socket library instead, just import the PythonServer instead of the SysServer with the following line:

from lightbug_http.python.server import PythonServer

You can then use all the regular server commands in the same way as with the default server.

Roadmap

Our vision is to develop three libraries, with lightbug_http (this repo) as a starting point:

• lightbug_http - HTTP infrastructure and basic API development
• lightbug_api - (coming later in 2024!) Tools to make great APIs fast, with support for OpenAPI spec and domain driven design
• lightbug_web - (release date TBD) Full-stack web framework for Mojo, similar to NextJS or SvelteKit

The idea is to get to a point where the entire codebase of a simple modern web application can be written in Mojo.

We don't make any promises, though -- this is just a vision, and whether we get there or not depends on many factors, including the support of the community.

See the open issues and submit your own to help drive the development of Lightbug.

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Contributing

Contributions are what make the open source community such an amazing place to learn, inspire, and create. Any contributions you make are greatly appreciated. See CONTRIBUTING.md for more details on how to contribute.

If you have a suggestion that would make this better, please fork the repo and create a pull request. You can also simply open an issue with the tag "enhancement". Don't forget to give the project a star!

1. Fork the Project
2. Create your Feature Branch (git checkout -b feature/AmazingFeature)
3. Commit your Changes (git commit -m 'Add some AmazingFeature')
4. Push to the Branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

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License

Distributed under the MIT License. See LICENSE.txt for more information.

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Contact

Valentin Erokhin

Project Link: https://github.com/saviorand/mojo-web

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Acknowledgments

We were drawing a lot on the following projects:

• FastHTTP (Golang)
• may_minihttp (Rust)
• FireTCP (One of the earliest Mojo TCP implementations!)

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Contributors

Want your name to show up here? See CONTRIBUTING.md!

_{Made with contrib.rocks.}