Example of the request object

The requests instance of the Request class contains information about... requests.

from pycnic.core import Handler, WSGI
from pycnic.errors import HTTP_400

class UsersHandler(Handler):

    def post(self):

        if not self.request.data.get("username"):
            raise HTTP_400("Yo dawg, you need to provide a username")

        return { 
            "username":self.request.data["username"],
            "authID":self.request.cookies.get("auth_id"),
            "yourIp":self.request.ip,
            "rawBody":self.request.body,
            "method":self.request.method,
            "json":self.request.data,
            "args":self.request.args,
            "jsonArgs":self.request.json_args,
            # Alternatively, self.request.environ.get("HTTP_X_FORWARDED_FOR")
            "xForwardedFor":self.request.get_header("X-Forwarded-For")
        }

class app(WSGI):
    routes = [ ("/user", UserHandler()) ]

In the above example, several request properties are accessed.

1. self.request.method - One of GET, POST, PUT, DELETE, OPTIONS.
2. self.request.data - When this property is read, it attempts to read the request body into a Python dictionary by way of JSON. If a body exists and it can't be read as JSON, then this sends an HTTP 400 JSON error to the client.
3. self.request.cookies - A dictionary of client cookies available for this domain.
4. self.request.ip - The IP address of the user. Pycnic attempts to use HTTP_X_FORWARDED_FOR if it's available, otherwise it settles on REMOTE_ADDR.
5. self.request.body - This is the raw deal. The body contains everything that's not a header, read from wsgi.input. This assumes CONTENT_LENGTH header was set.
6. self.request.args - This is a dictionary of query string parameters.
7. self.request.json_args - This is a dictionary of a loaded json string from the query parameters. For example, a request to /myurl?json=%7B%22foo%22%3A%22bar%22%7D would populate json_args with {"foo": "bar"}.