Thank you for your reply. My application requires cookies. All I want to do is display an appropriate message if the user doesn't have cookies enabled.
On Aug 3, 6:16 pm, Branko Vukelić <[email protected]> wrote: > On 2011-08-03 14:15 -0700, webpybuntu wrote: > > > it writes (or attempts to write) a cookie, reads it back, and then > > deletes it. it tests whether it read the correct value. However, using > > code like this, I always get None for val2 despite cookies being > > enabled. Why isn't this working and how can I make it work? > > Thanks. > > Because that's not how HTTP works. Here's how a normal work flow works: > > 1: Browser > Server "Howdy!" > 2: Browser < Server "Oh! Hi, here's a cookie" (cookie attached) > > 3: Browser > Server "I need some stuff. And btw, here's the cookie" > 4: Browser < Server "Hm, yes, that's my cookie. Ok. here's the stuff" > > or, it might go like this: > > 1. Browser > Server "Hello!" > 2. Browser < Server "Hi, man. How about a cookie?" (cookie attacked) > > 3. Browser > Server "I need some things." > 4. Browser < Server "Hm, you don't seem to have the cookie on you..." > > As you can see, there's always a request-response cycle in pairs. With > each request-response, the opportunity to set the cookie is when you are > making a response, and the browser then decides if it wants to show the > cookie next time it talks to the server. So the opportunity to check the > cookie is next response. > > Now the problem is the "next response". There isn't such a thing as next > response (unless you are 100% sure that your web app is only ever used > by one and the same browser that is). The illusion of the next response > is created using cookies and sessions. So if the browser didn't set the > cookie you sent it, you never know when that same browser comes to you > again. > > You don't have to worry about cookies to begin with. You should worry > about the problem you are trying to solve. Are you trying to track the > browser, to see if it's the same one you talked to before? Is there a > need to know if it's the same browser or maybe the operation you are > performing doesn't have to differentiate between different browsers, > etc. Those are the problems you should focus on. > > -- > Branko Vukelic > [email protected] > [email protected] > > Lead Developer > Herd Hound (tm) - Travel that doesn't bitewww.herdhound.com > > Love coffee? You might love Loveffee, too. > loveffee.appspot.com -- You received this message because you are subscribed to the Google Groups "web.py" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/webpy?hl=en.
