Learn SINATRA with Real Code Examples

Sinatra provides a DSL for defining HTTP routes and their handlers in Ruby.

Ideal for small web applications, microservices, and APIs.

Supports multiple request types (GET, POST, PUT, DELETE) out of the box.

Integrates easily with Rack-compatible middleware and libraries.

Encourages convention over configuration for rapid development.

Routing - map HTTP methods and paths to Ruby blocks

Middleware support - use Rack-compatible middleware

Request/Response objects - access headers, params, and body

Template rendering - embed Ruby in HTML views

Error handling and filters - before, after, and error blocks

Route - defines an endpoint and HTTP method

Handler - block of code executed when route is matched

Request - object representing HTTP request data

Response - object representing HTTP response

Middleware - optional layer for processing requests/responses

app.rb - main Sinatra application file

config.ru - Rack configuration file

views/ - template files (ERB, Haml, Slim)

public/ - static assets

Gemfile - gem dependencies

Define HTTP routes with corresponding handlers

Access query parameters and request body

Render templates for responses if needed

Use filters for pre/post-processing

Deploy app via Rack server or container

Beginner: Single-file web app with GET/POST routes

Intermediate: Multi-route app with templates and static assets

Advanced: RESTful API with middleware and authentication

Expert: Modular Sinatra app with multiple files and helpers

Architect: Service-oriented microservices architecture using Sinatra

Sinatra vs Rails: Lightweight, minimal vs full-featured MVC

Sinatra vs Hanami: Minimal DSL vs structured framework

Sinatra vs Grape: General web apps vs API-focused DSL

Sinatra vs Roda: Simplicity vs performance and routing focus

Sinatra vs Padrino: Minimal vs feature-rich extension of Sinatra

Route - maps HTTP request to handler

Handler - block executed for route

Middleware - pre/post-processing of requests/responses

Template - file for generating HTML

Rack - Ruby interface between web server and app