File: readme — Documentation by YARD 0.9.37

A lightweight, fast, and modular web framework for Ruby based on Rack. Lennarb supports Ruby (MRI) 3.4+

Features
Installation
Quick Start
Basic Usage
Documentation
Contributing
License

Features

Lightweight and modular architecture
High-performance routing system
Simple and intuitive API
Support for middleware
Flexible configuration options
Two implementation options:
Lennarb::App: Minimalist approach for single applications
Lennarb::Base: Extended version for mounting multiple applications

Installation

Add this line to your application’s Gemfile:

gem 'lennarb'

Or install it directly:

gem install lennarb

Quick Start

Create a simple application with routes:

require "lennarb"

app = Lennarb::App.new do
  get("/") do |req, res|
    res.html("<h1>Welcome to Lennarb!</h1>")
  end

  get("/hello/:name") do |req, res|
     name = req.params[:name]
     res.html("Hello, #{name}!")
  end
end

app.initialize!
run app  # In config.ru

Start with: rackup

Basic Usage

Creating a Simple Application

The Lennarb::App class is the core of the framework:

require "lennarb"

class MyApp < Lennarb::App
  # Define configuration
  config do
    mandatory :database_url, string
    optional :port, int, 9292
  end

  get("/") do |req, res|
    res.html("<h1>Welcome!</h1>")
  end

  post("/users") do |req, res|
    # Access request data
    data = req.body
      res.json({status: "created", data: data})
    end
  end

  # Define hooks
  before do |req, res|
    # Run before every request
    puts "Processing request: #{req.path}"
  end

  after do |req, res|
    # Run after every request
    puts "Completed request: #{req.path}"
  end

  # Define helper methods
  helpers do
    def format_date(date)
      date.strftime("%Y-%m-%d")
    end
  end
end

run MyApp.new.initialize!

Response Types

Lennarb provides various response methods:

# HTML response
res.html("<h1>Hello World</h1>")

# JSON response
res.json({message: "Hello World"})

# Plain text response
res.text("Plain text response")

# Redirect
res.redirect("/new-location")

# Custom status code
res.json({error: "Not found"}, status: 404)

Mounting Applications

For larger applications, use Lennarb::Base to mount multiple apps:

class API < Lennarb::App
  get("/users") do |req, res|
    res.json([{id: 1, name: "Alice"}, {id: 2, name: "Bob"}])
  end
end

class Admin < Lennarb::App  
  get("/dashboard") do |req, res|
    res.html("<h1>Admin Dashboard</h1>")
  end
end

class Application < Lennarb::Base
  # Add common middleware
  middleware do
    use Rack::Session::Cookie, secret: "your_secret"
  end

  # Mount applications at specific paths
  mount(API, at: "/api")
  mount(Admin, at: "/admin")
end

run Application.new.initialize!

Documentation

For more detailed information, please see:

Getting Started - Setup and first steps
Response - Response handling
Mounting Applications - Working with multiple apps
Performance - Benchmarks showing Lennarb’s routing algorithm efficiency

Contributing

Fork the repository
Create your feature branch (git checkout -b feature/amazing-feature)
Commit your changes (git commit -am 'Add amazing feature')
Push to the branch (git push origin feature/amazing-feature)
Open a Pull Request

This project uses the Developer Certificate of Origin and is governed by the Contributor Covenant.

License

MIT License - see the LICENSE file for details.

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