"""
Python's bundled WSGI server
Source code taken and improvements from the
"WSGI Tutorial" by Clodoaldo Pinto Neto at
https://wsgi.tutorial.codepoint.net/parsing-the-request-post
"""
import logging
from urllib.parse import parse_qs
from html import escape
logging.basicConfig(level=logging.INFO)
# Server IP
HOST_NAME = "localhost"
# Server port
PORT_NUMBER = 8080
html = """
Age: %(age)s
Hobbies: %(hobbies)s
\n"""
def application(environ, start_response):
# the environment variable CONTENT_LENGTH may be empty or missing
try:
request_body_size = int(environ.get("CONTENT_LENGTH", 0))
except ValueError:
request_body_size = 0
request_body = (
environ.get("wsgi.input").read(request_body_size)
if environ.get("wsgi.input")
else b""
)
# in the HTTP request body which is passed by the WSGI server
# in the file like wsgi.input environment variable.
if request_body:
environ_vars = parse_qs(request_body.decode())
else:
environ_vars = {}
age = environ_vars.get("age", [""])[0] # Returns the first age value.
hobbies = environ_vars.get("hobbies", []) # Returns a list of hobbies.
# Always escape user input to avoid script injection
age = escape(age)
hobbies = [escape(hobby) for hobby in hobbies]
response_body = html % { # Fill the above html template in
"checked-software": ("", "checked")["software" in hobbies],
"checked-tunning": ("", "checked")["tunning" in hobbies],
"age": age or "Empty",
"hobbies": ", ".join(hobbies or ["No Hobbies?"]),
}
# HTTP Status
STATUS = "200 OK"
# Now content type is text/html
RESPONSE_HEADERS = [
("Content-Type", "text/html"),
("Content-Length", str(len(response_body))),
]
# Start the response
try:
start_response(STATUS, RESPONSE_HEADERS)
except Exception as e:
logging.error(f"Error starting response: {e}")
start_response("500 Internal Server Error", [("Content-Type", "text/plain")])
return [b"Internal Server Error"]
return [response_body.encode("utf-8")]
server = None
try:
from wsgiref.simple_server import make_server
# Instantiate the server
server = make_server(
HOST_NAME, # The host name
PORT_NUMBER, # A port number where to wait for the request
application, # The application object name, in this case a function
)
logging.info(
f" WSGI Server running on http://{HOST_NAME}:{PORT_NUMBER}/ use to stop."
)
# Server serve forever
server.serve_forever()
except KeyboardInterrupt:
logging.error(" entered, stopping WSGI Server...")
if server:
# Close the server
server.socket.close()