(in-package :lisp-on-lines) (defclass db-access-slot-definition () ((column-name :initform nil :initarg :db-name :accessor slot-definition-column-name :documentation "If non-NIL, contains the name of the column this slot is representing.") (primary-key :initform nil :initarg :primary-key :accessor slot-definition-primary-key-p) (transient :initform nil :initarg :transient :accessor slot-definition-transient-p :documentation "If non-NIL, this slot should be treated as transient and ignored in all database related operations.") (not-null :initform nil :initarg :not-null :accessor slot-definition-not-null-p :documentation "If non-NIL, a NON NULL database constrained will be introduced.") (foreign-type :initform nil :initarg :foreign-type :initarg :references :accessor slot-definition-foreign-type) (unique :initform nil :initarg :unique :accessor slot-definition-unique) (on-delete :initform :cascade :initarg :on-delete :accessor slot-definition-on-delete :documentation "Action to be performed for this slot when the refering row in the database ceases to exist. Possible values: :CASCADE, :RESTRICT, :SET-NULL, :SET-DEFAULT. If this slot is not a foreign key, it does nothing.") (delayed-constraint :initform nil :accessor slot-definition-delayed-constraint :documentation "Closures adding constraints that, for some reason, could not be executed. If there's a slot with this attribute not-NIL in a class definition, then there's something wrong with its SQL counterpart."))) (defmethod slot-definition-column-name :around (slotd) (or (call-next-method) (slot-definition-name slotd))) (defclass db-access-class (standard-class) ((table-name :initarg :table-name :initform nil :accessor class-table-name) (indices :initarg :indices :initform () :reader class-indices) (unique :initarg :unique :initform () :reader class-unique) #+not!(connection-spec :initarg :connection-spec :initform nil :reader db-class-connection-spec) (unfinished-classes :initform nil :allocation :class :accessor class-unfinished-classes :documentation "A class allocated slot containing classes for whom not all the constraints could be applied.") (foreign-keys :initform nil :accessor class-foreign-keys :documentation "List of foreign-key slots.") (unique-keys :initform nil :accessor class-unique-keys :documentation "List of slots whose value should be unique.")) (:documentation "Metaclass for PostgreSQL aware classes. It takes two additional arguments in DEFTABLE: :INDICES (which slots are used as indices) and :CONNECTION-SPEC, which specifies how the class should connect to the database (its format is the same as in POSTMODERN:CONNECT-TOPLEVEL). If :CONNECTION-SPEC is not provided, SUBMARINE assumes it is a class created just for the sake of inheritance and does not create any tables for it.")) (defmethod validate-superclass ((class db-access-class) (superclass standard-class)) t) (defclass db-access-direct-slot-definition (standard-direct-slot-definition db-access-slot-definition) ()) (defmethod direct-slot-definition-class ((class db-access-class) &key &allow-other-keys) (find-class 'db-access-direct-slot-definition)) (defclass db-access-effective-slot-definition (standard-effective-slot-definition db-access-slot-definition) ()) (defmethod effective-slot-definition-class ((class db-access-class) &key &allow-other-keys) (find-class 'db-access-effective-slot-definition)) (defmethod compute-effective-slot-definition ((class db-access-class) name direct-slot-definitions) (declare (ignore name)) (let ((slotd (call-next-method))) (setf (slot-definition-primary-key-p slotd) (some #'slot-definition-primary-key-p direct-slot-definitions) (slot-definition-transient-p slotd) (every #'slot-definition-transient-p direct-slot-definitions) (slot-definition-foreign-type slotd) (slot-definition-foreign-type (car direct-slot-definitions)) (slot-definition-not-null-p slotd) (slot-definition-not-null-p (car direct-slot-definitions)) (slot-definition-unique slotd) (slot-definition-unique (car direct-slot-definitions)) (slot-definition-type slotd) (slot-definition-type (car direct-slot-definitions))) slotd)) (defun class-id-slot-definition (class) (find-if #'slot-definition-primary-key-p (class-slots class))) (defmethod class-table-name :around (class) (or (call-next-method) (class-name class))) (defclass standard-db-access-class (db-access-class) ()) (defun dao-id-column-name (class) (slot-definition-column-name (or (class-id-slot-definition class) (error "No ID slot (primary key) for ~A" class)))) (defclass described-db-access-class (standard-db-access-class described-class) ()) (defmethod initialize-instance :around ((class standard-db-access-class) &rest initargs &key (direct-superclasses '())) (declare (dynamic-extent initargs)) (if (loop for direct-superclass in direct-superclasses thereis (ignore-errors (subtypep direct-superclass 'standard-db-access-object))) (call-next-method) (apply #'call-next-method class :direct-superclasses (append direct-superclasses (list (find-class 'standard-db-access-object))) initargs))) (defmethod reinitialize-instance :around ((class standard-db-access-class) &rest initargs &key (direct-superclasses '() direct-superclasses-p)) (declare (dynamic-extent initargs)) (if (or (not direct-superclasses-p) (loop for direct-superclass in direct-superclasses thereis (ignore-errors (subtypep direct-superclass 'standard-db-access-object)))) (call-next-method) (apply #'call-next-method class :direct-superclasses (append direct-superclasses (list (find-class 'standard-db-access-object))) initargs))) (defclass standard-db-access-object (standard-object) ()) (defun find-dao (type id &key (table (class-table-name (find-class type))) id-column-name) "Get the dao corresponding to the given primary key, or return nil if it does not exist." (let ((row (first (query (:select '* :from table :where (:= id (or id-column-name (dao-id-column-name (find-class type))))))))) (make-dao-from-row type row))) (defmethod shared-initialize :after ((dao standard-db-access-object) slots &rest initargs) (let ((class (class-of dao))) (dolist (slotd (class-slots class)) (with-slots (foreign-type) slotd (when foreign-type (if (slot-boundp-using-class class dao slotd) (let ((value (slot-value-using-class class dao slotd))) (unless (typep value foreign-type) (if (connected-p *database*) (setf (slot-value-using-class class dao slotd) (find-dao foreign-type value)) (let ((obj (make-instance foreign-type))) (setf (slot-value-using-class (class-of obj) obj (class-id-slot-definition (class-of obj))) value))))))))))) (defgeneric dao-id (dao) (:method ((dao standard-db-access-object)) (let ((class (class-of dao))) (slot-value-using-class class dao (class-id-slot-definition class))))) (defun make-dao-from-row (type row &key slots) (let* ((class (find-class type)) (dao (make-instance class)) (slotds (class-slots class))) (loop :for val :in row :for slotd :in (or (loop :for slot :in slots :collect (find slot slotds :key #'slot-definition-name)) slotds) :do (setf (slot-value-using-class class dao slotd) val) :finally (return (reinitialize-instance dao))))) ;(defgeneric make-dao (type &rest initargs) #+nil(defun make-dao (type initargs) "Create a DAO of the given `TYPE' and initialize it according to the values of the alist `INITARGS'. `Initargs' may contain additional values, not used in the initialization proccess." (let ((instance (make-instance type))) (iter (for slot in (slots-of instance)) (setf (slot-value instance (slot-definition-name slot)) (let ((the-value (cdr (assoc (intern (symbol-name (slot-definition-name slot)) 'keyword) initargs)))) (if (foreign-type-p slot) (make-instance (sb-pcl:slot-definition-type slot) :id the-value) the-value)))) instance))