lofigui

Latest: v0.17.39

Lofi GUI - A minimalist Go library for creating really simple web-based GUIs for CLI tools and small projects. It provides a print-like interface for building lightweight web UIs with minimal complexity.

The application is where you have a single real object (e.g. machine or long-running process) which then has a number of pages around it to show various aspects of it.

In the spirit of Niklaus Wirth — computer systems should be simpler and more readable. Every dependency, every JavaScript byte, every layer of indirection has to justify itself against the alternative of just printing HTML. See Philosophy for the longer argument.

Overview

lofigui provides a print-like interface for building lightweight web applications with minimal complexity. Perfect for:

• Creating quick GUIs for command-line tools
• Internal tools for small teams (1-10 users)
• Single-process or single-object front-ends
• Rapid prototyping without JavaScript overhead

Key Features

• Simple API: Print-like interface (Print(), Markdown(), HTML(), Table())
• No JavaScript: Pure HTML/CSS using the Bulma framework
• Single binary: Deploy as one executable, no dependencies
• WebAssembly: Same code runs in the browser via WASM
• Responsive layouts: Bulma-based templates with optional base.html inheritance — see example 03 (Style Sampler) for the catalogue

Quick Start

package main

import (
    "net/http"
    "git.bytestone.uk/hum3/lofigui"
)

func model(app *lofigui.App) {
    lofigui.Print("Hello world")
    app.EndAction()
}

func main() {
    ctrl, _ := lofigui.NewControllerWithLayout(lofigui.LayoutNavbar, "My App")
    app := lofigui.NewApp()
    app.SetController(ctrl)
    app.SetDisplayURL("/display")

    http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
        app.HandleRoot(w, r, model, true)
    })
    http.HandleFunc("/display", func(w http.ResponseWriter, r *http.Request) {
        app.HandleDisplay(w, r)
    })
    http.HandleFunc("/favicon.ico", lofigui.ServeFavicon)
    http.ListenAndServe(":8080", nil)
}

Element

Your project is essentially a web site. To make design simple you completely refresh pages so no code for partial refreshes. To make things dynamic it has to be asynchronous, using goroutines for background processing.

Like a normal terminal program you essentially just print things to a screen but now have the ability to print enriched objects.

Model View Controller architecture

All I really want to do is to write the model. The controller and view (in the browser and templating system) are a necessary evil. The controller includes the routing and web server. The controller is split between the app (single instance) and a model-specific controller. The view is the HTML templating (html/template in Go, Jinja2 in Python) and the browser.

Buffer

In order to decouple the display from the output and be able to refresh, you need to buffer the output. It is more efficient to buffer the output in the browser but more complicated. Moving the buffer to the server simplifies the software but requires you to refresh the whole page. lofigui relies on hyperlinks to perform updates. HTMX plays nicely here for improving interactivity (examples 09-10).

Installation

go get git.bytestone.uk/hum3/lofigui

Examples & Documentation

See the documentation site for interactive examples (including WASM demos), research notes, and the roadmap.

To run examples locally, use Task:

task --list              # Show all available tasks
task go-example:09       # Run any Go example by number

Python

A Python implementation also exists with the same API using FastAPI and Jinja2. See Python Notes for installation, API reference, and development instructions.

Roadmap

See ROADMAP.md for planned features and future direction.

Contributing

Contributions are welcome! Please see CONTRIBUTING.md for guidelines.

License

MIT License - see LICENSE file for details.

Author

Humphrey Drummond - hum3@drummond.info

Links

Documentation	https://h3-lofigui.statichost.page/
PyPI	https://pypi.org/project/lofigui/
Source (Codeberg)	https://git.bytestone.uk/hum3/lofigui
Mirror (GitHub)	https://github.com/drummonds/lofigui