Future standard GUI library

[Frank Millman]

"Chris Angelico" <rosuav at gmail.com> wrote in message 
news:CAPTjJmq_m4y0UXXt3JqYThJj9CKbsvp+Z2PGF5v_31xLrgfr4Q at mail.gmail.com...
> On Fri, Jun 14, 2013 at 3:39 PM, Frank Millman <frank at chagford.com> wrote:
>>
>> In my case, it is either-or. I do not just do field-by-field validation, 
>> I
>> do field-by-field submission. The server builds up a record of the data
>> entered while it is being entered. When the user selects 'Save', it does 
>> not
>> resend the entire form, it simply sends a message to the server telling 
>> it
>> to process the data it has already stored.
>
> Ah, I see what you mean. What I was actually saying was that it's
> mandatory to check on the server, at time of form submission, and
> optional to pre-check (either on the client itself, for simple
> syntactic issues, or via AJAX or equivalent) for faster response.
>
> As a general rule, I would be inclined to go with a more classic
> approach for reasons of atomicity. What happens if the user never gets
> around to selecting Save? Does the server have a whole pile of data
> that it can't do anything with? Do you garbage-collect that
> eventually? The classic model allows you to hold off inserting
> anything into the database until it's fully confirmed, and then do the
> whole job in a single transaction.
>

The data is just stored in memory in a 'Session' object. I have a 
'keep-alive' feature that checks if the client is alive, and removes the 
session with all its data if it detects that the client has gone away. 
Timeout is configurable, but I have it set to 30 seconds at the moment.

The session is removed immediately if the user logs off. He is warned if 
there is unsaved data.

Frank