(use awful spiffy extras data-structures)

(enable-sxml #t)

(debug-log "debug.log")
(error-log "error.log")

(define-page "/test"
  (lambda ()
    (add-javascript
     "var source = new EventSource('/sse');                                                                                                                             
      source.onmessage = function (event) {                                                                                                                             
          document.body.innerHTML = event.data;                                                                                                                         
      };")
    ""))

(define (send-sse-headers)
  (let ((resp (update-response (current-response)
                               code: 200
                               reason: "OK"
                               headers: (headers '((content-type text/event-stream)
                                                   (cache-control no-cache)
                                                   (connection keep-alive)
                                                   (transfer-encoding chunked))
                                                 (response-headers (current-response))))))
    (parameterize ((current-response resp))
      (write-logged-response))))

(define (send-sse-data data)
  (display (conc "data: " data "\n\n")
           (response-port (current-response)))
  (finish-response-body (current-response)))

(define-page "/sse"
  (lambda ()
    (send-sse-headers)
    (let loop ()
      (send-sse-data (random 10))
      (thread-sleep! 5)
      (loop))))


;;; Firefox developer console
;; GET http://zion:8080/test [HTTP/1.1 200 OK 16 ms]
;; GET http://zion:8080/sse [HTTP/1.1 500 Internal server error 51 ms]
;; Firefox could not establish connection with server http://zion:8080/sse
;; URL: http:/zion:8080/sse
;; Method: GET
;; Status code: HTTP/1.1 500 Internal server error
;; Response headers:
;; Server:	Spiffy/5.2 (Running on Chicken 4.8.0.5)
;; Date:	Tue, 24 Jun 2014 01:19:03 GMT
;; Content-Type:	text/html
;; Content-Length:	62

;;; debug-log
;; thread131: Incoming request from 192.168.1.2
;; thread131: Handling request from 192.168.1.2
;; thread131: Kept alive
;; thread131: Handling request from 192.168.1.2
;; thread131: Kept alive
;; thread131: Error:
;; read operation timed out
;; 60000
;; 5

;;         Call history:

;;         spiffy.scm:181: with-output-to-file
;;         spiffy.scm:187: newline
;;         spiffy.scm:611: handle-next-request
;;         spiffy.scm:467: call-with-current-continuation
;;         spiffy.scm:467: with-exception-handler
;;         spiffy.scm:467: ##sys#call-with-values
;;         spiffy.scm:467: ##sys#call-with-values
;;         spiffy.scm:475: call/cc
;;         spiffy.scm:475: intarweb#read-request
;;         intarweb.scm:613: safe-read-line
;;         intarweb.scm:140: http-line-limit
;;         intarweb.scm:141: http-line-limit
;;         intarweb.scm:141: read-line
;;         spiffy.scm:467: k657
;;         spiffy.scm:467: g661
;;         spiffy.scm:469: with-output-to-string           <--


;; thread131: Closing off
;; thread132: Incoming request from 192.168.1.2
;; thread132: Handling request from 192.168.1.2
;; thread132: Kept alive
;; thread132: Handling request from 192.168.1.2
;; thread132: Kept alive

;;; error-log - none written