-! Copyright (C) 2004 Chris Double.
-! Copyright (C) 2006, 2008 Slava Pestov.
-! See http://factorcode.org/license.txt for BSD license.
-USING: http http.server io kernel math namespaces
-continuations calendar sequences assocs hashtables
-accessors arrays alarms quotations combinators fry
-http.server.redirection furnace assocs.lib urls ;
-IN: furnace.callbacks
-
-SYMBOL: responder
-
-TUPLE: callback-responder responder callbacks ;
-
-: <callback-responder> ( responder -- responder' )
- H{ } clone callback-responder boa ;
-
-TUPLE: callback cont quot expires alarm responder ;
-
-: timeout 20 minutes ;
-
-: timeout-callback ( callback -- )
- [ alarm>> cancel-alarm ]
- [ dup responder>> callbacks>> delete-at ]
- bi ;
-
-: touch-callback ( callback -- )
- dup expires>> [
- dup alarm>> [ cancel-alarm ] when*
- dup '[ , timeout-callback ] timeout later >>alarm
- ] when drop ;
-
-: <callback> ( cont quot expires? -- callback )
- f callback-responder get callback boa
- dup touch-callback ;
-
-: invoke-callback ( callback -- response )
- [ touch-callback ]
- [ quot>> request get exit-continuation get 3array ]
- [ cont>> continue-with ]
- tri ;
-
-: register-callback ( cont quot expires? -- id )
- <callback> callback-responder get callbacks>> set-at-unique ;
-
-: forward-to-url ( url -- * )
- ! When executed inside a 'show' call, this will force a
- ! HTTP 302 to occur to instruct the browser to forward to
- ! the request URL.
- <temporary-redirect> exit-with ;
-
-: cont-id "factorcontid" ;
-
-: forward-to-id ( id -- * )
- ! When executed inside a 'show' call, this will force a
- ! HTTP 302 to occur to instruct the browser to forward to
- ! the request URL.
- <url>
- swap cont-id set-query-param forward-to-url ;
-
-: restore-request ( pair -- )
- first3 exit-continuation set request set call ;
-
-SYMBOL: post-refresh-get?
-
-: redirect-to-here ( -- )
- ! Force a redirect to the client browser so that the browser
- ! goes to the current point in the code. This forces an URL
- ! change on the browser so that refreshing that URL will
- ! immediately run from this code point. This prevents the
- ! "this request will issue a POST" warning from the browser
- ! and prevents re-running the previous POST logic. This is
- ! known as the 'post-refresh-get' pattern.
- post-refresh-get? get [
- [
- [ ] t register-callback forward-to-id
- ] callcc1 restore-request
- ] [
- post-refresh-get? on
- ] if ;
-
-SYMBOL: current-show
-
-: store-current-show ( -- )
- ! Store the current continuation in the variable 'current-show'
- ! so it can be returned to later by 'quot-id'. Note that it
- ! recalls itself when the continuation is called to ensure that
- ! it resets its value back to the most recent show call.
- [ current-show set f ] callcc1
- [ restore-request store-current-show ] when* ;
-
-: show-final ( quot -- * )
- [ redirect-to-here store-current-show ] dip
- call exit-with ; inline
-
-: resuming-callback ( responder request -- id )
- url>> cont-id query-param swap callbacks>> at ;
-
-M: callback-responder call-responder* ( path responder -- response )
- '[
- , ,
-
- [ callback-responder set ]
- [ request get resuming-callback ] bi
-
- [
- invoke-callback
- ] [
- callback-responder get responder>> call-responder
- ] ?if
- ] with-exit-continuation ;
-
-: show-page ( quot -- )
- [ redirect-to-here store-current-show ] dip
- [
- [ ] t register-callback swap call exit-with
- ] callcc1 restore-request ; inline
-
-: quot-id ( quot -- id )
- current-show get swap t register-callback ;
-
-: quot-url ( quot -- url )
- quot-id f swap cont-id associate derive-url ;