((connection-spec :accessor connection-spec :initarg :connection-spec)
(database-type :accessor pool-database-type :initarg :pool-database-type)
(free-connections :accessor free-connections
- :initform (make-array 5 :fill-pointer 0 :adjustable t))
+ :initform (make-array 5 :fill-pointer 0 :adjustable t))
(all-connections :accessor all-connections
- :initform (make-array 5 :fill-pointer 0 :adjustable t))
+ :initform (make-array 5 :fill-pointer 0 :adjustable t))
(lock :accessor conn-pool-lock
- :initform (make-process-lock "Connection pool"))))
+ :initform (make-process-lock "Connection pool"))))
(defun acquire-from-conn-pool (pool)
+ "Try to find a working database connection in the pool or create a new
+one if needed. This performs 1 query against the DB to ensure it's still
+valid. When possible (postgres, mssql) that query will be a reset
+command to put the connection back into its default state."
(or (with-process-lock ((conn-pool-lock pool) "Acquire from pool")
- (when (plusp (length (free-connections pool)))
+ (when (plusp (length (free-connections pool)))
(let ((pconn (vector-pop (free-connections pool))))
;; test if connection still valid.
- ;; Currently, on supported on MySQL
- (cond
- ((eq :mysql (database-type pconn))
- (handler-case
- (database-query "SHOW ERRORS LIMIT 1" pconn nil nil)
- (error (e)
- ;; we could check for error type 2006 for "SERVER GONE AWAY",
- ;; but, it's safer just to disconnect the pooled conn for any error
- (warn "Database connection ~S had an error when attempted to be acquired from the pool:
+ ;; (e.g. db reboot -> invalid connection )
+ (handler-case
+ (case (database-underlying-type pconn)
+ (:postgresql
+ (database-execute-command "RESET ALL" pconn))
+ (:mysql
+ (database-query "SHOW ERRORS LIMIT 1" pconn nil nil))
+ (:mssql
+ ;; rpc escape sequence since this can't be called as a normal sp.
+ ;;http://msdn.microsoft.com/en-us/library/aa198358%28SQL.80%29.aspx
+ (database-execute-command "{rpc sp_reset_connection}" pconn))
+ (T
+ (database-query "SELECT 1;" pconn '(integer) nil)))
+ (sql-database-error (e)
+ ;; we could check for a specific error,
+ ;; but, it's safer just to disconnect the pooled conn for any error ?
+ (warn "Database connection ~S had an error when attempted to be acquired from the pool:
~S
Disconnecting.~%"
- pconn e)
- (ignore-errors (database-disconnect pconn))
- nil)
- (:no-error (res fields)
- (declare (ignore res fields))
- pconn)))
- (t
- pconn)))))
+ pconn e)
+ (ignore-errors (database-disconnect pconn))
+ nil)
+ (:no-error (&rest args)
+ (declare (ignore args))
+ pconn)))))
(let ((conn (connect (connection-spec pool)
- :database-type (pool-database-type pool)
- :if-exists :new
+ :database-type (pool-database-type pool)
+ :if-exists :new
:make-default nil)))
- (with-process-lock ((conn-pool-lock pool) "Acquire from pool")
- (vector-push-extend conn (all-connections pool))
- (setf (conn-pool conn) pool))
- conn)))
+ (with-process-lock ((conn-pool-lock pool) "Acquire from pool")
+ (vector-push-extend conn (all-connections pool))
+ (setf (conn-pool conn) pool))
+ conn)))
(defun release-to-conn-pool (conn)
(let ((pool (conn-pool conn)))
(defun clear-conn-pool (pool)
(with-process-lock ((conn-pool-lock pool) "Clear pool")
(loop for conn across (all-connections pool)
- do (setf (conn-pool conn) nil)
- ;; disconnect may error if remote side closed connection
- (ignore-errors (disconnect :database conn)))
+ do (setf (conn-pool conn) nil)
+ ;; disconnect may error if remote side closed connection
+ (ignore-errors (disconnect :database conn)))
(setf (fill-pointer (free-connections pool)) 0)
(setf (fill-pointer (all-connections pool)) 0))
nil)
if not found"
(with-process-lock (*db-pool-lock* "Find-or-create connection")
(let* ((key (list connection-spec database-type))
- (conn-pool (gethash key *db-pool*)))
+ (conn-pool (gethash key *db-pool*)))
(unless conn-pool
- (setq conn-pool (make-instance 'conn-pool
- :connection-spec connection-spec
- :pool-database-type database-type))
- (setf (gethash key *db-pool*) conn-pool))
+ (setq conn-pool (make-instance 'conn-pool
+ :connection-spec connection-spec
+ :pool-database-type database-type))
+ (setf (gethash key *db-pool*) conn-pool))
conn-pool)))
(defun acquire-from-pool (connection-spec database-type &optional pool)
(with-process-lock (*db-pool-lock* "Disconnect pooled")
(maphash
#'(lambda (key conn-pool)
- (declare (ignore key))
- (clear-conn-pool conn-pool))
+ (declare (ignore key))
+ (clear-conn-pool conn-pool))
*db-pool*)
(when clear (clrhash *db-pool*)))
t)
; "Start all stream in the pool recording actions of TYPES"
; (dolist (con (pool-connections pool))
; (start-sql-recording :type types
-; :database (connection-database con))))
+; :database (connection-database con))))
;(defun pool-stop-sql-recording (pool &key (types :command))
; "Start all stream in the pool recording actions of TYPES"
; (dolist (con (pool-connections pool))
; (stop-sql-recording :type types
-; :database (connection-database con))))
+; :database (connection-database con))))
;(defmacro with-database-connection (pool &body body)
; `(let ((connection (obtain-connection ,pool))