src/rofl.lisp

   1 (in-package :lisp-on-lines)
   2
   3 ;;;; NB: These could really be in upstream
   4
   5 ;;;; * A PLIST reader for postmodern.
   6 (postmodern::def-row-reader symbol-plist-row-reader (fields)
   7   (let ((symbols (map 'list (lambda (desc)
   8                    (postmodern::from-sql-name (postmodern::field-name desc))) fields)))
   9     (loop :while (postmodern::next-row)
  10           :collect (loop :for field :across fields
  11                          :for symbol :in symbols
  12                          :nconc (list symbol (postmodern::next-field field))))))
  13
  14 (s-sql::def-sql-op :between (n start end)
  15   `(,@(s-sql::sql-expand n) " BETWEEN " ,@(s-sql::sql-expand start) " AND " ,@(s-sql::sql-expand end)))
  16
  17 (s-sql::def-sql-op :case (&rest clauses)
  18   `("CASE " ,@(loop for (test expr) in clauses collect (format nil "WHEN ~A THEN ~A " (s-sql::sql-expand test) (s-sql::sql-expand expr))) "END"))
  19
  20
  21 ;;;; now the rofl code itself
  22 (defun %query (query)
  23   (cl-postgres:exec-query *database* (sql-compile query) 'symbol-plist-row-reader))
  24
  25 (defun select (&rest query)
  26   (%query (cons :select query)))
  27
  28 (defun select-only (num &rest query)
  29   (let ((results (%query `(:limit ,(cons :select query) ,num))))
  30     (if (eql 1 num)
  31         (first results)
  32         results)))
  33
  34 (defun insert-into (table &rest values-plist)
  35   (postmodern:execute
  36    (postmodern:sql-compile `(:insert-into ,table :set ,@values-plist))))
  37
  38
  39 (defclass db-access-slot-definition ()
  40   ((column-name  :initform nil
  41                  :initarg :db-name
  42                  :initarg :column
  43                  :accessor slot-definition-column-name
  44                :documentation
  45               "If non-NIL, contains the name of the column this slot is representing.")
  46    (primary-key :initform nil
  47                 :initarg :primary-key
  48                 :accessor slot-definition-primary-key-p)
  49    (transient  :initform nil :initarg :transient :accessor slot-definition-transient-p
  50                :documentation
  51               "If non-NIL, this slot should be treated as transient and
  52 ignored in all database related operations.")
  53    (not-null :initform nil :initarg :not-null :accessor slot-definition-not-null-p
  54              :documentation "If non-NIL, a NON NULL database
  55 constrained will be introduced.")
  56    (foreign-type
  57     :initform nil
  58     :initarg :foreign-type
  59     :initarg :references
  60     :accessor slot-definition-foreign-type)
  61    (unique :initform nil :initarg :unique :accessor slot-definition-unique)
  62
  63
  64    (on-delete :initform :cascade :initarg :on-delete :accessor slot-definition-on-delete
  65               :documentation "Action to be performed for this slot
  66 when the refering row in the database ceases to exist. Possible
  67 values: :CASCADE, :RESTRICT, :SET-NULL, :SET-DEFAULT. If this slot is
  68 not a foreign key, it does nothing.")
  69    (delayed-constraint :initform nil :accessor slot-definition-delayed-constraint
  70                         :documentation "Closures adding constraints
  71 that, for some reason, could not be executed. If there's a slot with
  72 this attribute not-NIL in a class definition, then there's something
  73 wrong with its SQL counterpart.")))
  74
  75
  76 (defclass db-access-class (standard-class)
  77   ((table-name :initarg :table-name :initform nil :accessor class-table-name)
  78    (indices :initarg :indices :initform () :reader class-indices)
  79    (unique :initarg :unique :initform () :reader class-unique)
  80    #+not!(connection-spec :initarg :connection-spec :initform nil :reader db-class-connection-spec)
  81
  82    (unfinished-classes :initform nil :allocation :class :accessor class-unfinished-classes
  83                        :documentation "A class allocated slot
  84 containing classes for whom not all the constraints could be
  85 applied.")
  86    (foreign-keys :initform nil :accessor class-foreign-keys
  87                  :documentation "List of foreign-key slots.")
  88    (unique-keys :initform nil :accessor class-unique-keys
  89                 :documentation "List of slots whose value should be unique."))
  90   (:documentation "Metaclass for PostgreSQL aware classes. It takes
  91 two additional arguments in DEFTABLE: :INDICES (which slots are used
  92 as indices) and :CONNECTION-SPEC, which specifies how the class should
  93 connect to the database (its format is the same as in
  94 POSTMODERN:CONNECT-TOPLEVEL). If :CONNECTION-SPEC is not provided,
  95 SUBMARINE assumes it is a class created just for the sake of
  96 inheritance and does not create any tables for it."))
  97
  98 (defmethod validate-superclass
  99            ((class db-access-class)
 100             (superclass standard-class))
 101   t)
 102
 103
 104 (defclass db-access-direct-slot-definition (standard-direct-slot-definition
 105                                             db-access-slot-definition)
 106   ())
 107
 108 (defmethod direct-slot-definition-class
 109            ((class db-access-class) &key &allow-other-keys)
 110   (find-class 'db-access-direct-slot-definition))
 111
 112 (defclass db-access-effective-slot-definition
 113     (standard-effective-slot-definition
 114      db-access-slot-definition)
 115   ())
 116
 117 (defmethod effective-slot-definition-class
 118            ((class db-access-class) &key &allow-other-keys)
 119   (find-class 'db-access-effective-slot-definition))
 120
 121 (defmethod compute-effective-slot-definition
 122            ((class db-access-class) name direct-slot-definitions)
 123   (declare (ignore name))
 124   (let ((slotd (call-next-method)))
 125     (setf (slot-definition-primary-key-p slotd)
 126           (some #'slot-definition-primary-key-p direct-slot-definitions)
 127           (slot-definition-column-name slotd)
 128           (or (let ((slot (find-if #'slot-definition-column-name direct-slot-definitions)))
 129                 (when slot
 130                   (slot-definition-column-name slot)))
 131               name)
 132           (slot-definition-transient-p slotd)
 133           (every #'slot-definition-transient-p direct-slot-definitions)
 134           (slot-definition-foreign-type slotd)
 135           (slot-definition-foreign-type (car direct-slot-definitions))
 136           (slot-definition-not-null-p slotd)
 137           (slot-definition-not-null-p (car direct-slot-definitions))
 138           (slot-definition-unique slotd) (slot-definition-unique (car direct-slot-definitions))
 139           (slot-definition-type slotd) (slot-definition-type (car direct-slot-definitions)))
 140     slotd))
 141
 142 (defun class-id-slot-definition (class)
 143   (find-if #'slot-definition-primary-key-p
 144            (class-slots class)))
 145
 146 (defmethod class-table-name :around (class)
 147   (or (call-next-method)
 148       (class-name class)))
 149
 150 (defclass standard-db-access-class (db-access-class)
 151   ())
 152
 153 (defmethod ensure-class-using-class :around ((class standard-db-access-class) name &rest args &key direct-slots &allow-other-keys)
 154        (let ((direct-slots (loop for slot in direct-slots
 155                               collect (let* ((sname (getf slot :name))
 156                                              (readers (getf slot :readers))
 157                                              (writers (getf slot :writers)))
 158                                         (setf (getf slot :readers)
 159                                               (cons (intern (format nil "~A.~A"
 160                                                                     name sname)) readers))
 161                                         (setf (getf slot :writers)
 162                                               (cons `(setf ,(intern (format nil "~A.~A"
 163                                                                     name sname))) writers))
 164                                         slot))))
 165
 166
 167        (apply #'call-next-method class name :direct-slots direct-slots args)))
 168
 169 (defun dao-id-column-name (class)
 170   (slot-definition-column-name
 171    (or (class-id-slot-definition class)
 172        (error "No ID slot (primary key) for ~A" class))))
 173
 174 (defclass described-db-access-class (standard-db-access-class described-class)
 175   ())
 176
 177 (defmethod initialize-instance :around ((class standard-db-access-class) &rest initargs &key (direct-superclasses '()))
 178   (declare (dynamic-extent initargs))
 179   (if (loop for direct-superclass in direct-superclasses
 180          thereis (ignore-errors (subtypep direct-superclass 'standard-db-access-object)))
 181       (call-next-method)
 182       (apply #'call-next-method
 183              class
 184              :direct-superclasses
 185              (append direct-superclasses
 186                      (list (find-class 'standard-db-access-object)))
 187              initargs)))
 188
 189 (defmethod reinitialize-instance :around ((class standard-db-access-class) &rest initargs &key (direct-superclasses '() direct-superclasses-p))
 190   (declare (dynamic-extent initargs))
 191   (if (or (not direct-superclasses-p)
 192           (loop for direct-superclass in direct-superclasses
 193              thereis (ignore-errors (subtypep direct-superclass 'standard-db-access-object))))
 194       (call-next-method)
 195       (apply #'call-next-method
 196              class
 197              :direct-superclasses
 198              (append direct-superclasses
 199                      (list (find-class 'standard-db-access-object)))
 200              initargs)))
 201
 202 (defclass standard-db-access-object (standard-object)
 203   ())
 204
 205 (defun %select-objects (type select-fn query)
 206   (mapcar (curry 'make-object-from-plist type)
 207           (apply select-fn (intern (format nil "*"))
 208                  (if (string-equal (first query) :from)
 209                      query
 210                      (append `(:from ,type) query)))))
 211
 212 (defun select-objects (type &rest query)
 213   (%select-objects type #'select query))
 214
 215 (defun select-only-n-objects (n type &rest query)
 216   (let ((fields (if (eq :fields (car query))
 217                     (loop
 218                        :for cons :on (cdr query)
 219                        :if (not (keywordp (car cons)))
 220                        :collect (car cons) into fields
 221                        :else :do
 222                          (setf query cons)
 223                          (return (nreverse (print fields)))
 224                        :finally
 225                          (setf query cons)
 226                          (return (nreverse (print fields))))
 227
 228                     (list (intern "*")))))
 229     (let ((results
 230            (%query
 231             (print `(:limit (:select
 232                       ,@fields
 233                       ,@(if (string-equal (first query) :from)
 234                             (print query)
 235                             (append `(:from ,type) query)))
 236                      ,n)))))
 237     (if (eql 1 n)
 238         (make-object-from-plist type (first results))
 239         (mapcar (curry 'make-object-from-plist type) results)))))
 240
 241 (defun make-object-from-plist (type plist)
 242   (let* ((class (find-class type))
 243          (object (make-instance class))
 244          (slotds (class-slots class)))
 245
 246     (loop
 247        :for (key val) :on plist :by #'cddr
 248        :do
 249        (dolist (slotd (remove key slotds
 250                               :key #'slot-definition-column-name
 251                               :test-not #'string-equal))
 252
 253              (setf (slot-value-using-class class object slotd) val))
 254        :finally (return (reinitialize-instance object)))))
 255
 256 (defun make-object (type &rest plist)
 257   (make-object-from-plist type plist))
 258
 259
 260
 261 (defun find-dao (type id
 262                  &key (table (class-table-name (find-class type)))
 263                       id-column-name)
 264
 265   "Get the dao corresponding to the given primary key,
 266 or return nil if it does not exist."
 267   (let ((plist
 268               (select-only 1 '*
 269                :from table
 270                :where (list ':= id (or id-column-name
 271                                  (dao-id-column-name
 272                                   (find-class type)))))))
 273     (make-object-from-plist type plist)))
 274
 275 (defmethod shared-initialize :after ((dao standard-db-access-object)
 276                                      slots &rest initargs)
 277   (let ((class (class-of dao))
 278         (foreign-key))
 279     (dolist (slotd (class-slots class))
 280       (with-slots (foreign-type) slotd
 281         (when foreign-type
 282           (when (consp foreign-type)
 283             (setf foreign-key (cdr foreign-type)
 284                   foreign-type (car foreign-type)))
 285           (if (slot-boundp-using-class class dao slotd)
 286               (let ((value (slot-value-using-class class dao slotd)))
 287                 (unless (typep value foreign-type)
 288                   (if (connected-p *database*)
 289                       (setf (slot-value-using-class class dao slotd)
 290                             (find-dao foreign-type value))
 291                       (let ((obj (make-instance foreign-type)))
 292                         (setf (slot-value-using-class
 293                                (class-of obj)
 294                                obj
 295                                (class-id-slot-definition (class-of obj)))
 296                               value)))))))))))
 297
 298 (defgeneric dao-id (dao)
 299   (:method ((dao standard-db-access-object))
 300     (let ((class (class-of dao)))
 301
 302       (slot-value-using-class class dao (class-id-slot-definition class)))))
 303
 304 (defun make-dao-from-row (type row &key slots)
 305   (let* ((class (find-class type))
 306          (dao (make-instance class))
 307          (slotds (class-slots class)))
 308     (loop
 309          :for val :in row
 310          :for slotd
 311        :in (or
 312             (loop
 313                :for slot :in slots
 314                :collect (find slot slotds
 315                               :key #'slot-definition-name))
 316             slotds)
 317          :do (setf (slot-value-using-class class dao slotd) val)
 318          :finally (return (reinitialize-instance dao)))))
 319
 320 ;(defgeneric make-dao (type &rest initargs)
 321 #+nil(defun make-dao (type initargs)
 322   "Create a DAO of the given `TYPE' and initialize it according
 323   to the values of the alist `INITARGS'. `Initargs' may contain
 324   additional values, not used in the initialization proccess."
 325   (let ((instance (make-instance type)))
 326     (iter (for slot in (slots-of instance))
 327           (setf (slot-value instance (slot-definition-name slot))
 328                 (let ((the-value (cdr (assoc (intern (symbol-name (slot-definition-name slot)) 'keyword) initargs))))
 329                   (if (foreign-type-p slot)
 330                       (make-instance (sb-pcl:slot-definition-type slot) :id the-value)
 331                       the-value))))
 332     instance))
 333
 334
 335
 336
 337