-(in-package "SPECIALIZABLE")
-
-(defstruct accept-node
- (name (error "missing name"))
- (children nil)
- (q nil))
-(defun print-accept-tree (tree stream)
- (let (*stack*)
- (declare (special *stack*))
- (labels ((walk (fun node)
- (let ((*stack* (cons node *stack*)))
- (declare (special *stack*))
- (mapc (lambda (x) (walk fun x)) (accept-node-children node)))
- (funcall fun node))
- (stringify (node)
- (case (length *stack*)
- (0 "*/*")
- (1 (format nil "~A/*" (accept-node-name node)))
- (2 (format nil "~A/~A" (accept-node-name (car *stack*)) (accept-node-name node))))))
- (let ((first t))
- (walk
- (lambda (x)
- (let ((q (accept-node-q x)))
- (when q
- (format stream "~:[, ~;~]" first)
- (format stream "~A~:[;q=~A~;~]" (stringify x) (= q 1.0) q)
- (setf first nil))))
- tree)))))
-(defmethod print-object ((o accept-node) s)
- (if (accept-node-name o)
- (call-next-method)
- (pprint-logical-block (s nil)
- (print-unreadable-object (o s :type t)
- (print-accept-tree o s)))))
-
-(defun q (media-type accept-tree)
- (let* ((pos (position #\/ media-type))
- (type (subseq media-type 0 pos))
- (subtype (subseq media-type (1+ pos)))
- (type-node (find type (accept-node-children accept-tree) :key #'accept-node-name :test #'string=))
- (subtype-node (and type-node (find subtype (accept-node-children type-node) :key #'accept-node-name :test #'string=))))
- (or (and subtype-node (accept-node-q subtype-node))
- (and type-node (accept-node-q type-node))
- (accept-node-q accept-tree))))
-
-(defun q-ok (media-type accept-tree)
- (let ((q (q media-type accept-tree)))
- (and q (> q 0) q)))
-
-(defun insert (range q tree)
- (labels ((ensure-node (range tree)
- (cond
- ((null range) tree)
- (t (ensure-node (cdr range)
- (or (find (car range) (accept-node-children tree)
- :key #'accept-node-name :test #'string=)
- (car (push
- (make-accept-node :name (car range))
- (accept-node-children tree)))))))))
- (let ((node (ensure-node range tree)))
- ;; we could choose different behaviour here
- (setf (accept-node-q node) q))
- tree))
-
-(defun parse-accept-string (string)
- (flet ((whitespacep (x)
- (member x '(#\Space #\Tab))))
- (let ((string (remove-if #'whitespacep string))
- (result (make-accept-node :name nil)))
- (cl-ppcre:do-register-groups (type subtype qp q)
- ;; not desperately error-proof
- ("([a-z]*|\\*)/([a-z0-9]*|\\*)(;q=([01]\\.[0-9]*))?(,|$)" string result)
- (if qp
- (setf q (float (+ (digit-char-p (char q 0))
- (/ (parse-integer q :start 2)
- (expt 10 (- (length q) 2))))))
- (setf q 1.0))
- (let ((range (and (string/= type "*")
- (cons type (and (string/= subtype "*")
- (list subtype))))))
- (insert range q result))))))
-\f
-;;; FIXME: tiebreaker predicate (maybe defaulting to string<)?
-(defclass accept-specializer (extended-specializer)
- ((media-type :initarg :media-type :type string :reader media-type)))
-(defmethod print-object ((o accept-specializer) s)
- (print-unreadable-object (o s :type t)
- (format s "~S" (media-type o))))
-;;; FIXME: would be cute to have sb-pcl:generalizer to inherit from.
-;;; Or maybe specializable:extended-generalizer could handle the NEXT
-;;; functionality?
-(defclass accept-generalizer ()
- ((header :initarg :header :reader header)
- (tree)
- (next :initarg :next :reader next)))
-(defmethod print-object ((o accept-generalizer) s)
- (print-unreadable-object (o s :type t)
- (print-accept-tree (tree o) s)))
-(defmethod tree ((x accept-generalizer))
- (if (slot-boundp x 'tree)
- (slot-value x 'tree)
- (setf (slot-value x 'tree) (parse-accept-string (header x)))))
-(defclass accept-generic-function (specializable-generic-function)
- ()
- (:metaclass sb-mop:funcallable-standard-class))
-
-(define-extended-specializer accept (gf arg)
- (declare (ignore gf))
- (make-instance 'accept-specializer :media-type arg))
-(defmethod sb-pcl:unparse-specializer-using-class
- ((gf accept-generic-function) (specializer accept-specializer))
- `(accept ,(media-type specializer)))
-(defmethod sb-pcl::same-specializer-p
- ((s1 accept-specializer) (s2 accept-specializer))
- (string= (media-type s1) (media-type s2)))
-
-(defmethod generalizer-of-using-class ((gf accept-generic-function) (arg tbnl:request))
- (make-instance 'accept-generalizer
- :header (tbnl:header-in :accept arg)
- :next (call-next-method)))
-(defmethod generalizer-equal-hash-key
- ((gf accept-generic-function) (g accept-generalizer))
- `(accept-generalizer ,(header g)))
-(defmethod specializer-accepts-generalizer-p ((gf accept-generic-function) (s accept-specializer) (generalizer accept-generalizer))
- (values (q-ok (media-type s) (tree generalizer)) t))
-(defmethod specializer-accepts-generalizer-p ((gf accept-generic-function) (s accept-specializer) generalizer)
- (values nil t))
-(defmethod specializer-accepts-generalizer-p ((gf accept-generic-function) (s sb-mop:specializer) (generalizer accept-generalizer))
- (specializer-accepts-generalizer-p gf s (next generalizer)))
-
-(defmethod specializer-accepts-p ((specializer accept-specializer) obj)
- nil)
-(defmethod specializer-accepts-p ((specializer accept-specializer) (obj tbnl:request))
- (q-ok (media-type specializer) (parse-accept-string (tbnl:header-in :accept obj))))
-
-(defmethod specializer< ((gf accept-generic-function) (s1 accept-specializer) (s2 accept-specializer) generalizer)
- (cond
- ((string= (media-type s1) (media-type s2)) '=)
- (t (let ((q1 (q (media-type s1) (tree generalizer)))
- (q2 (q (media-type s2) (tree generalizer))))
- (cond
- ((= q1 q2) '=)
- ((< q1 q2) '>)
- (t '<))))))
-(defmethod specializer< ((gf accept-generic-function) (s1 accept-specializer) (s2 class) generalizer)
- '<)
-(defmethod specializer< ((gf accept-generic-function) (s1 accept-specializer) (s2 sb-mop:eql-specializer) generalizer)
- '>)
-(defmethod specializer< ((gf accept-generic-function) (s1 sb-mop:specializer) (s2 accept-specializer) generalizer)
- (ecase (specializer< gf s2 s1 generalizer)
- ((>) '<)
- ((<) '>)))
-(defmethod specializer< ((gf accept-generic-function) (s1 sb-mop:specializer) (s2 sb-mop:specializer) (g accept-generalizer))
- (specializer< gf s1 s2 (next g)))
-\f
-(defvar *actual-content-type*)
-(defgeneric handle-content-type (x))
-(define-method-combination content-negotiation ()
- ((around (:around))
- (before (:before))
- (primary () :required t)
- (after (:after)))
- (:arguments request)
- (labels ((call-methods (methods)
- (mapcar #'(lambda (method)
- `(call-method ,method))
- methods))
- (transform (primaries)
- (let ((method (car primaries))
- (nexts (cdr primaries)))
- `(make-method
- (progn
- (let ((request-specializer (car (sb-mop:method-specializers ,method))))
- (when (typep request-specializer 'accept-specializer)
- (setf *actual-content-type* (media-type request-specializer))))
- (throw 'content-negotiation (call-method ,method ,@(and nexts `((,(transform nexts))))))))))
- (wrap (form)
- `(let ((*actual-content-type*))
- (multiple-value-prog1
- ,form
- (handle-content-type ,request)))))
- (let ((form (if (or before after (rest primary))
- `(multiple-value-prog1
- (progn ,@(call-methods before)
- (catch 'content-negotiation (call-method ,(transform primary))))
- ,@(call-methods (reverse after)))
- `(catch 'content-negotiation (call-method ,(transform primary))))))
- (if around
- (wrap `(call-method ,(first around)
- (,@(rest around) (make-method ,form))))
- (wrap form)))))
-(define-method-combination content-negotiation/or ()
- ((around (:around))
- (primary () :required t))
- (:arguments request)
- (labels ((transform/1 (method)
- `(make-method
- (progn
- (let ((s (car (sb-mop:method-specializers ,method))))
- (when (typep s 'accept-specializer)
- (setf *actual-content-type* (media-type s))))
- (call-method ,method))))
- (transform (primaries)
- (mapcar #'(lambda (x) `(call-method ,(transform/1 x)))
- primaries))
- (wrap (form)
- `(let ((*actual-content-type*))
- (multiple-value-prog1
- ,form
- (handle-content-type ,request)))))
- (let ((form (if (rest primary)
- `(or ,@(transform primary))
- `(call-method ,(transform/1 (car primary))))))
- (if around
- (wrap `(call-method ,(first around)
- (,@(rest around) (make-method ,form))))
- (wrap form)))))
-
-(defmethod generalizer-of-using-class ((gf accept-generic-function) (s string))
- (make-instance 'accept-generalizer
- :header s
- :next (call-next-method)))
-(defmethod specializer-accepts-p ((s accept-specializer) (string string))
- (q-ok (media-type s) (parse-accept-string string)))
-
-(defmethod handle-content-type ((x tbnl:request))
- (setf (tbnl:content-type*) *actual-content-type*))
-(defmethod handle-content-type ((x string))
- (format t "~&Content-Type: ~A" *actual-content-type*))
-
-(defgeneric respond (request)
- (:generic-function-class accept-generic-function)
- (:method-combination list))
-(defmethod respond list (request)
- t)
-(defmethod respond list ((s string))
- 'string)
-(defmethod respond list ((s (accept "text/html")))
- "text/html")
-(defmethod respond list ((s (accept "audio/mp3")))
- "audio/mp3")
-
-(defgeneric cn-test (request)
- (:generic-function-class accept-generic-function)
- (:method-combination content-negotiation))
-(defmethod cn-test ((request (accept "text/html")))
- 'html)
-(defmethod cn-test ((request (accept "text/plain")))
- 'plain)
-(defmethod cn-test ((request (accept "image/webp")))
- 'webp)
-(defmethod cn-test ((request (accept "audio/mp3")))
- (call-next-method)
- 'mp3)
-(defmethod cn-test :after (request)
- (print 'after))
-
-(defgeneric cn/or-test (request)
- (:generic-function-class accept-generic-function)
- (:method-combination content-negotiation/or))
-
-(defmethod cn/or-test or ((request (accept "audio/mp3")))
- 'mp3)
-(defmethod cn/or-test or ((request (accept "image/webp")))
- 'webp)
-(defmethod cn/or-test :around ((request t))
- (print :around)
- (call-next-method))
projects / specializable.git / blobdiff