Question

In a link in a web page I want to pass a GET parameter to a GAE web app in Python. So, if someone access the web app through this link, one form with some input fields will show up. If someone access the web app, i.e. by typing the web app url, another form with more input fields will show up.
Does someone know the best way to do this?
I tried the following but it didn’t work:

 def get(self): 
    q=self.request.get("q") 
    if q is None: 
     #show form with all fields 
    else: 
     #show form without all fields 
  def post(self): 
     #here I care about the added fields only if nothing was passed as a GET parameter

Answer 1

By default, get() returns the empty string (”) if the requested argument is not in the request (see documentation).

So for checking if an argument is missing, use

if q == '':

or

if len(q) == 0: