;;; Code:
(require 'emacs-web-server-status-codes)
-(require 'mail-parse)
+(require 'mail-parse) ; to parse multipart data in headers
+(require 'mm-encode) ; to look-up mime types for files
+(require 'url-util) ; to decode url-encoded params
(require 'eieio)
+(eval-when-compile (require 'cl))
(require 'cl-lib)
(defclass ews-server ()
(port :initarg :port :accessor port :initform nil)
(clients :initarg :clients :accessor clients :initform nil)))
+(defclass ews-client ()
+ ((leftover :initarg :leftover :accessor leftover :initform "")
+ (boundary :initarg :boundary :accessor boundary :initform nil)
+ (headers :initarg :headers :accessor headers :initform (list nil))))
+
(defvar ews-servers nil
"List holding all ews servers.")
(defvar ews-time-format "%Y.%m.%d.%H.%M.%S.%N"
"Logging time format passed to `format-time-string'.")
-(defun ews-start (handler port &optional log-buffer host)
+(defun ews-start (handler port &optional log-buffer &rest network-args)
"Start a server using HANDLER and return the server object.
HANDLER should be a list of cons of the form (MATCH . ACTION),
then the function ACTION is called with two arguments, the
process and the request object.
+Any supplied NETWORK-ARGS are assumed to be keyword arguments for
+`make-network-process' to which they are passed directly.
+
For example, the following starts a simple hello-world server on
port 8080.
8080)
"
- (let ((server (make-instance 'ews-server :handler handler :port port)))
+ (let ((server (make-instance 'ews-server :handler handler :port port))
+ (log (when log-buffer (get-buffer-create log-buffer))))
(setf (process server)
- (make-network-process
+ (apply
+ #'make-network-process
:name "ews-server"
:service (port server)
:filter 'ews-filter
- :server 't
- :nowait 't
+ :server t
+ :nowait t
:family 'ipv4
- :host host
- :plist (list :server server)
- :log (when log-buffer
- (lexical-let ((buf log-buffer))
- (lambda (server client message)
- (let ((c (process-contact client)))
- (with-current-buffer buf
- (goto-char (point-max))
- (insert (format "%s\t%s\t%s\t%s"
- (format-time-string ews-time-format)
- (first c) (second c) message)))))))))
+ :plist (append (list :server server)
+ (when log (list :log-buffer log)))
+ :log (when log
+ (lambda (proc client message)
+ (let ((c (process-contact client))
+ (buf (plist-get (process-plist proc) :log-buffer)))
+ (with-current-buffer buf
+ (goto-char (point-max))
+ (insert (format "%s\t%s\t%s\t%s"
+ (format-time-string ews-time-format)
+ (first c) (second c) message))))))
+ network-args))
(push server ews-servers)
server))
(mapc #'delete-process (append (mapcar #'car (clients server))
(list (process server)))))
-(defun ews-parse (string)
- (cond
- ((string-match "^GET \\([^[:space:]]+\\) \\([^[:space:]]+\\)$" string)
- (list (cons :GET (match-string 1 string))
- (cons :TYPE (match-string 2 string))))
- ((string-match "^\\([^[:space:]]+\\): \\(.*\\)$" string)
- (list (cons (intern (concat ":" (upcase (match-string 1 string))))
- (match-string 2 string))))
- (:otherwise (message "[ews] bad header: %S" string) nil)))
+(defvar ews-http-common-methods '(GET HEAD POST PUT DELETE TRACE)
+ "HTTP methods from http://www.w3.org/Protocols/rfc2616/rfc2616-sec9.html.")
+
+(defvar ews-http-method-rx
+ (format "^\\(%s\\) \\([^[:space:]]+\\) \\([^[:space:]]+\\)$"
+ (mapconcat #'symbol-name ews-http-common-methods "\\|")))
+
+(defun ews-parse (proc string)
+ (cl-flet ((to-keyword (s) (intern (concat ":" (upcase (match-string 1 s))))))
+ (cond
+ ((string-match ews-http-method-rx string)
+ (let ((method (to-keyword (match-string 1 string)))
+ (url (match-string 2 string)))
+ (if (string-match "?" url)
+ (cons (cons method (substring url 0 (match-beginning 0)))
+ (url-parse-query-string (url-unhex-string
+ (substring url (match-end 0))) ))
+ (list (cons method url)))))
+ ((string-match "^\\([^[:space:]]+\\): \\(.*\\)$" string)
+ (list (cons (to-keyword string) (match-string 2 string))))
+ (:otherwise (ews-error proc "bad header: %S" string) nil))))
+
+(defun ews-trim (string)
+ (while (and (> (length string) 0)
+ (or (and (string-match "[\r\n]" (substring string -1))
+ (setq string (substring string 0 -1)))
+ (and (string-match "[\r\n]" (substring string 0 1))
+ (setq string (substring string 1))))))
+ string)
+
+(defun ews-parse-multipart/form (string)
+ ;; ignore empty and non-content blocks
+ (when (string-match "Content-Disposition:[[:space:]]*\\(.*\\)\r\n" string)
+ (let ((dp (mail-header-parse-content-disposition (match-string 1 string))))
+ (cons (cdr (assoc 'name (cdr dp)))
+ (ews-trim (substring string (match-end 0)))))))
(defun ews-filter (proc string)
- ;; TODO: parse post DATA, see the relevent test, and use these
- ;; - mail-header-parse-content-disposition
- ;; - mail-header-parse-content-type
(with-slots (handler clients) (plist-get (process-plist proc) :server)
- ;; register new client
- (unless (assoc proc clients) (push (list proc "") clients))
- (let* ((client (assoc proc clients)) ; clients are (proc pending headers)
- (pending (concat (cadr client) string))
- (last-index 0) index in-post)
+ (unless (assoc proc clients)
+ (push (cons proc (make-instance 'ews-client)) clients))
+ (let ((c (cdr (assoc proc clients))))
+ (when (not (eq (catch 'close-connection
+ (if (ews-do-filter proc c string)
+ (ews-call-handler proc (cdr (headers c)) handler)
+ :keep-open))
+ :keep-open))
+ (setq clients (assq-delete-all proc clients))
+ (delete-process proc)))))
+
+(defun ews-do-filter (proc client string)
+ "Return non-nil when finished and the client may be deleted."
+ (with-slots (leftover boundary headers) client
+ (let ((pending (concat leftover string))
+ (delimiter (if boundary
+ (regexp-quote (concat "\r\n--" boundary))
+ "\r\n"))
+ (last-index 0) index tmp-index)
(catch 'finished-parsing-headers
;; parse headers and append to client
- (while (setq index (string-match "\r\n" pending last-index))
- ;; double \r\n outside of post data -> done w/headers, call handler
- (when (and (not in-post) (= last-index index))
- (throw 'finished-parsing-headers
- (when (ews-call-handler proc (cddr client) handler)
- (setq clients (assq-delete-all proc clients))
- (delete-process proc))))
- (if in-post
- ;; build up post data, maybe set in-post to boundary
- (error "TODO: handle POST data")
- (let ((this (ews-parse (substring pending last-index index))))
- (if (eql (caar this) :CONTENT-TYPE)
- (error "TODO: handle POST data")
- (setcdr (last client) this))))
- (setq last-index (+ index 2)))
- (setcar (cdr client) (substring pending last-index))))))
+ (while (setq index (string-match delimiter pending last-index))
+ (let ((tmp (+ index (length delimiter))))
+ (cond
+ ;; Double \r\n outside of post data means we are done
+ ;; w/headers and should call the handler.
+ ((and (not boundary) (= last-index index))
+ (throw 'finished-parsing-headers t))
+ ;; Parse a URL
+ ((eq boundary :application/x-www-form-urlencoded)
+ (mapc (lambda (pair) (setcdr (last headers) (list pair)))
+ (url-parse-query-string
+ (ews-trim (substring pending last-index))))
+ (throw 'finished-parsing-headers t))
+ ;; Build up multipart data.
+ (boundary
+ (setcdr (last headers)
+ (list (ews-parse-multipart/form
+ (ews-trim
+ (substring pending last-index index)))))
+ ;; a boundary suffixed by "--" indicates the end of the headers
+ (when (and (> (length pending) (+ tmp 2))
+ (string= (substring pending tmp (+ tmp 2)) "--"))
+ (throw 'finished-parsing-headers t)))
+ ;; Standard header parsing.
+ (:otherwise
+ (let ((this (ews-parse proc (substring pending last-index index))))
+ (if (and (caar this) (eql (caar this) :CONTENT-TYPE))
+ (cl-destructuring-bind (type &rest data)
+ (mail-header-parse-content-type (cdar this))
+ (cond
+ ((string= type "multipart/form-data")
+ (when (assoc 'boundary data)
+ (setq boundary (cdr (assoc 'boundary data)))
+ (setq delimiter (concat "\r\n--" boundary))))
+ ((string= type "application/x-www-form-urlencoded")
+ (setq boundary (intern (concat ":" (downcase type)))))
+ (:otherwise
+ (ews-error proc "TODO: handle content type: %S" type))))
+ (setcdr (last headers) this)))))
+ (setq last-index tmp)))
+ (setq leftover (ews-trim (substring pending last-index)))
+ nil))))
(defun ews-call-handler (proc request handler)
(catch 'matched-handler
(string-match (cdr match)
(cdr (assoc (car match) request))))
(and (functionp match) (funcall match request)))
- (throw 'matched-handler (funcall function proc request)))))
+ (throw 'matched-handler
+ (condition-case e
+ (funcall function proc request)
+ (error (ews-error proc "Caught Error: %S" e)))))))
handler)
- (error "[ews] no handler matched request:%S" request)))
+ (ews-error proc "no handler matched request: %S" request)))
+
+(defun ews-error (proc msg &rest args)
+ (let ((buf (plist-get (process-plist proc) :log-buffer))
+ (c (process-contact proc)))
+ (when buf
+ (with-current-buffer buf
+ (goto-char (point-max))
+ (insert (format "%s\t%s\t%s\tEWS-ERROR: %s"
+ (format-time-string ews-time-format)
+ (first c) (second c)
+ (apply #'format msg args)))))
+ (apply #'ews-send-500 proc msg args)))
\f
;;; Convenience functions to write responses
(setcdr (last headers) (list "" ""))
(process-send-string proc (mapconcat #'identity headers "\r\n"))))
+(defun ews-send-500 (proc &rest msg-and-args)
+ "Send 500 \"Internal Server Error\" to PROC with an optional message."
+ (ews-response-header proc 500
+ '("Content-type" . "text/plain"))
+ (process-send-string proc (if msg-and-args
+ (apply #'format msg-and-args)
+ "500 Internal Server Error"))
+ (throw 'close-connection nil))
+
+(defun ews-send-404 (proc &rest msg-and-args)
+ "Send 404 \"Not Found\" to PROC with an optional message."
+ (ews-response-header proc 404
+ '("Content-type" . "text/plain"))
+ (process-send-string proc (if msg-and-args
+ (apply #'format msg-and-args)
+ "404 Not Found"))
+ (throw 'close-connection nil))
+
+(defun ews-send-file (proc path &optional mime-type)
+ "Send PATH to PROC.
+Optionally explicitly set MIME-TYPE, otherwise it is guessed by
+`mm-default-file-encoding'."
+ (let ((mime (or mime-type
+ (mm-default-file-encoding path)
+ "application/octet-stream")))
+ (ews-response-header proc 200 (cons "Content-type" mime))
+ (process-send-string proc
+ (with-temp-buffer
+ (insert-file-contents-literally path)
+ (buffer-string)))))
+
(provide 'emacs-web-server)
;;; emacs-web-server.el ends here