Hi all,
Using 6.0.1
I was under the (maybe mistaken) impression that calling response/...
terminated the servlet thread. It seems though that it doesn't. I was
hoping to use response as an early exit, so that my servlets look like:
e.g.,
(define (user/exists request)
(let* [
(params (request-bindings request))
(username (exists-binding? 'username params))
(response (make-hash))
]
; validate request
(unless username
(response/json (hasheq 'success #f 'msg "missing username" ))
; get request parameters
(set! username (extract-binding/single 'username params))
:
; send a real response
(response/json response )
))
(define (response/json obj . cookies )
(response/output
(λ (op) (write-json obj op))
#:code 200
#:message #"OK"
#:seconds (current-seconds)
#:mime-type #"application/javascript"
#:headers (map cookie->header cookies)
))
I expected that unless would bail out if the test fails. However,
execution charges ahead into code that extracts post parameters and/or
cookie values and then I get a contract error that terminates the
servlet ... usually before my own error response is sent.
Is response supposed to terminate the servlet? If not, can I wrap a
let/ec around the whole servlet and do something like:
(define (user/exists request)
(let/ec fail
(let* [
(params (request-bindings request))
(username (exists-binding? 'username params))
(response (make-hash))
]
; validate request
(unless username
(response/json (hasheq 'success #f 'msg "missing username" )
(fail))
; get request parameters
(set! username (extract-binding/single 'username params))
:
; send a real response
(response/json response )
)))
or do I have to arrange that the response always is the last value produced?
Thanks,
George
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