mmo-project/lisp/server/server.lisp

(load "~/quicklisp/setup.lisp")
(ql:quickload '(clack websocket-driver alexandria))

(defvar *connections* (make-hash-table))

(defun broadcast-to-room (connection message)
  (let ((message (format nil "{\"uid\":\"~a\", \"msg\":~a}"
                         (gethash connection *connections*)
                         message)))
    (loop :for con :being :the :hash-key :of *connections* :do
          (websocket-driver:send con message))))

(defun handle-new-connection (con)
  (let ((user (format nil "~a" (random 100000))))
  (setf (gethash con *connections*) user)
    (websocket-driver:send con (format nil "{\"uid\":\"~a\",\"msg\":{\"cmd\":\"login\"}}" user))))

(defun handle-close-connection (connection)
  (let ((message (format nil "{ \"uid\":\"~a\",\"msg\":{\"cmd\":\"login\"}}"
                         (gethash connection *connections*))))
    (remhash connection *connections*)
    (loop :for con :being :the :hash-key :of *connections* :do
          (websocket-driver:send con message))))

(defun chat-server (env)
  (let ((ws (websocket-driver:make-server env)))
    (websocket-driver:on :open ws
                         (lambda () (handle-new-connection ws)))

    (websocket-driver:on :message ws
                         (lambda (msg)
                           (broadcast-to-room ws msg)))

    (websocket-driver:on :error ws
			 (lambda (msg)
			   (format t "~a" msg)))

    (websocket-driver:on :close ws
                         (lambda (&key code reason)
                           (declare (ignore code reason))
                           (handle-close-connection ws)))
    (lambda (responder)
      (declare (ignore responder))
      (websocket-driver:start-connection ws))))

(defvar *chat-handler* (clack:clackup #'chat-server :port 5000))