[racket] #lang web-server

Correct. Almost no one needs to worry about this.

serve/servlet takes a function, not a module, and so that function
runs in the module namespace is came from (which is the same one for
the server and probably everything else). serve/servlet effectively
bundles your servlet into the server and they share everything.

Servlets only come from modules if they are read from the disk by a
running server in response to a request. With serve/servlet, this is
if they are in servlets-root. If you use the command-line tool or the
"standard dispatcher sequence", then it is much more relevant. I don't
recommend using that basically ever.

Jay

On Fri, Mar 16, 2012 at 8:29 AM, Robby Findler
<robby at eecs.northwestern.edu> wrote:
> Wait: I don't understand. I do 'racket main.rkt'. That file contains a
> call to serve/servlet (with #:stateless? #t) and passes a function
> 'start' that gets called with requests. I think that maybe what you're
> saying below is that what I'm doing is not "servlets" and what happens
> is just what I would expect: there is no fancy monkey business with
> namespaces (unless my code does it).
>
> Is that right?
>
> Robby
>
> On Fri, Mar 16, 2012 at 9:22 AM, Jay McCarthy <jay.mccarthy at gmail.com> wrote:
>> Servlets do *not* share the same module instantiations. Each is in a
>> different unique one. They only shared web-server/http and net/url (so
>> that structs can communicate between the server and them.) However, if
>> you use serve/servlet, this is irrelevant because you probably are not
>> instantiating different servlets anyways.
>>
>> It is possible to explicitly share any number of modules:
>>
>> http://docs.racket-lang.org/web-server-internal/dispatch-servlets.html?q=make-servlet-namespace#(mod-path._web-server/configuration/namespace)
>>
>> and the #:servlet-namespace argument to serve/servlet
>>
>> As I mentioned above, this is most useful for sharing structs and states.
>>
>> Jay
>>
>> On Thu, Mar 15, 2012 at 8:33 PM, Robby Findler
>> <robby at eecs.northwestern.edu> wrote:
>>> Another question: do all servlets (in a single running server) share
>>> the same module instantiations?
>>>
>>> I ask because I want to store some data that the user of the web
>>> server is supplying (on the disk) and I want to be sure that only one
>>> thread reads and writes the data. So if all servlets share the same
>>> module instantiations, I'm set. But if they don't, then I'm in
>>> trouble.
>>>
>>> Robby
>>
>>
>>
>> --
>> Jay McCarthy <jay at cs.byu.edu>
>> Assistant Professor / Brigham Young University
>> http://faculty.cs.byu.edu/~jay
>>
>> "The glory of God is Intelligence" - D&C 93



-- 
Jay McCarthy <jay at cs.byu.edu>
Assistant Professor / Brigham Young University
http://faculty.cs.byu.edu/~jay

"The glory of God is Intelligence" - D&C 93