Can I do conditional GET requests from Flash / Flex / AS?

Question

I have a Flex client that loads data from a server to display a chart. This data may change, so the client regularly repeats the request. Since the result may require some work to retrieve, I'm going to have the server detect if the result has changed, and issue a 304 status if it hasn't.

I haven't seen any headers in the Flash Player's requests which would indicate that it's already handling conditional GETs. Also, the HTTPService API doesn't seem to provide anything, either. Does that mean, Flash can't do this, or how can I implement this myself?

With regards to cookies, which aren't supported in Flash, I have heard the suggestion to build my own HTTP client on top of the Socket class. This might solve this issue, too, but frankly, I'm really not keen on doing that.

As an alternative, I could just cache the result page and send it again, but so far, the API tries to utilize semantics that are already built into HTTP, and I'd like to keep it that way.

Answer 1

In my experience Flash has dealt properly with HTTP 304 responses, though I haven't tried to change application behavior based on whether content was new or cached.

You may be able to detect the 304 responses and change your behavior if you use URLLoader instead of HTTPService and listen for the httpStatus event.

Not sure how your cookie question is related. Take a look at CookieUtil for accessing cookies from Flash through Javascript.

Answer 2

Take a look at another SO post:

http://stackoverflow.com/questions/153420/is-it-feasible-to-create-a-rest-client-with-flex#153589

I believe this will clarify some things for you.