Python Servlets

The motivation for Python Servlets comes from the Java programming language and related technologies that were designed at the end of the past century. The Java Servlet API has evolved with over 20 years of contribution from millions of software developers. The API is fast, efficient, and secure. It is also full featured, providing a standard interface for common services which include access mechanisms, session management, and application security.

An Exciting Example

The HelloServlet example is useful for introducing the mechanisms integrating a Python Servlet into a Web Application.

HelloServlet.py
from pythonx.servlet.http.HttpServlet import HttpServlet

class HelloServlet(HttpServlet):
    def doGet(self, request, response):
        response.setContentType("text/plain")
        response.getWriter().println("Hello, World!")

An application developer has some flexibility regarding where this file is located in the filesystem.

Returning Binary Data

The ImageServlet example demonstrates how to return non-textual data.

ImageServlet.py

from pythonx.servlet.http.HttpServlet import HttpServlet

class ImageServlet(HttpServlet):

    def doGet(self, request, response):
        # Set response content type
        response.setContentType("image/png")

        # Get file contents
        file = open("website/icons/paige-450.png", "rb")
        contents = file.read()
        file.close()

        # Return file contents
        outputStream = response.getOutputStream()
        outputStream.write(contents)

Sample Servlet Executions

Several servlets are available to demonstrate their execution.

Hello	A trivial first servlet that generates a simple message
Image	An example of a servlet that returns binary data (an image file).
BMI Form	This example presents a simple page containing a form that is passed to a servlet when the form is submitted to the server. The example was scraped from the Internet from an instructional site to teach Java Servlets.
Redirect	The redirect servlet demonstrates how a servlet passes control to a PSP. This is a useful trick that developers can use if they would like to use servlets to process logic and yield control to PSP to render the output returned to the client.