Introduction to Japronto

Japronto is one of the fastest Python web frameworks, designed with performance in mind. Its name, derived from the Portuguese word “japronto” (meaning “already done” or “ready”), is a testament to its focus on speed and efficiency. Let’s dive deep into Japronto’s APIs with comprehensive examples to demonstrate its capabilities and usage.

Getting Started

To install Japronto, you can use pip:

  pip install japronto

Here’s a basic example of setting up a simple web application with Japronto:

  from japronto import Application

  def hello(request):
      return request.Response(text="Hello, World!")

  app = Application()
  app.router.add_route('/', hello)
  app.run()

Japronto API Highlights

1. Handling Routes

Japronto provides a powerful and simple way to define routes. Here’s how:

  from japronto import Application

  def welcome(request):
      return request.Response(text="Welcome to my Japronto app!")

  def about(request):
      return request.Response(text="This app is built with Japronto!")

  app = Application()
  app.router.add_route('/', welcome)
  app.router.add_route('/about', about)
  app.run()

2. Query Parameters

You can easily handle query parameters in Japronto:

  def query_handler(request):
      name = request.query.get('name', 'Guest')
      return request.Response(text=f"Hello, {name}!")

  app.router.add_route('/greet', query_handler)
  

3. JSON Responses

Japronto makes it simple to return JSON responses:

  import json

  def json_handler(request):
      data = {"message": "Hello, JSON!"}
      return request.Response(json.dumps(data), mime_type='application/json')

  app.router.add_route('/json', json_handler)

4. Handling POST Requests

Japronto can handle POST requests with ease:

  def post_handler(request):
      name = request.json.get('name', 'Guest')
      return request.Response(text=f"Thanks for posting, {name}!")

  app.router.add_route('/post', post_handler, method='POST')

5. Middleware

Middleware in Japronto lets you process requests before they reach your handlers:

  def middleware(request, handler):
      request.custom = "Hello from middleware!"
      response = handler(request)
      response.text += f" {request.custom}"
      return response

  app.router.add_middleware(middleware)

6. Custom Exception Handling

You can add custom exception handling to manage errors gracefully:

  from japronto.handlers import ErrorHandler

  class MyErrorHandler(ErrorHandler):
      def handle_request_error(self, request, exception):
          return request.Response(text="Custom Error Handling")

  app.error_handler = MyErrorHandler()

Complete Application Example

Let’s build a complete API-based application combining several features of Japronto:

  from japronto import Application
  import json

  def home(request):
      return request.Response(text="Welcome to Japronto API Example!")

  def greet_user(request):
      name = request.query.get('name', 'Guest')
      return request.Response(text=f"Hello, {name}!")

  def json_response(request):
      data = {"status": "success", "message": "Your request was processed"}
      return request.Response(json.dumps(data), mime_type='application/json')

  def post_data(request):
      name = request.json.get('name', 'Unnamed')
      return request.Response(text=f"Received POST data for {name}")

  def middleware(request, handler):
      request.custom = "Processed through middleware"
      response = handler(request)
      response.text += f" | Middleware says: {request.custom}"
      return response

  app = Application()
  app.router.add_route('/', home)
  app.router.add_route('/greet', greet_user)
  app.router.add_route('/json', json_response)
  app.router.add_route('/post_data', post_data, method='POST')
  app.router.add_middleware(middleware)
  app.run()

Conclusion

Japronto is an impressive Python web framework that delivers unparalleled speed and simplicity. Its APIs are intuitive, enabling rapid development for both simple applications and complex projects. Start building with Japronto today!