Source code for pydal.connection

# -*- coding: utf-8 -*-
import os

from ._compat import exists
from ._globals import GLOBAL_LOCKER, THREAD_LOCAL
from .helpers.classes import UseDatabaseStoredFile

[docs]class ConnectionPool(object): POOLS = {} check_active_connection = True @staticmethod
[docs] def set_folder(folder): THREAD_LOCAL.folder = folder
[docs] def close(self, action='commit', really=True): #: if we have an action (commit, rollback), try to execute it succeeded = True if action: try: if callable(action): action(self) else: getattr(self, action)() except: #: connection had some problems, we want to drop it succeeded = False #: if we have pools, we should recycle the connection (but only when # we succeded in `action`, if any and `len(pool)` is good) if self.pool_size and succeeded: GLOBAL_LOCKER.acquire() pool = ConnectionPool.POOLS[self.uri] if len(pool) < self.pool_size: pool.append(self.connection) really = False GLOBAL_LOCKER.release() #: closing the connection when we `really` want to, in particular: # - when we had an exception running `action` # - when we don't have pools # - when we have pools but they're full if really: try: self.close_connection() except: pass #: always unset `connection` attribute self.connection = None
[docs] def close_all_instances(action): """ to close cleanly databases in a multithreaded environment """ dbs = getattr(THREAD_LOCAL, 'db_instances', {}).items() for db_uid, db_group in dbs: for db in db_group: if hasattr(db, '_adapter'): db._adapter.close(action) getattr(THREAD_LOCAL, 'db_instances', {}).clear() getattr(THREAD_LOCAL, 'db_instances_zombie', {}).clear() if callable(action): action(None) return
[docs] def find_or_make_work_folder(self): #this actually does not make the folder. it has to be there self.folder = getattr(THREAD_LOCAL, 'folder', '') if os.path.isabs(self.folder) and \ isinstance(self, UseDatabaseStoredFile) and \ self.folder.startswith(os.getcwd()): self.folder = os.path.relpath(self.folder, os.getcwd()) # Creating the folder if it does not exist if False and self.folder and not exists(self.folder): os.mkdir(self.folder)
[docs] def after_connection_hook(self): """Hook for the after_connection parameter""" if callable(self._after_connection): self._after_connection(self) self.after_connection()
[docs] def after_connection(self): #this it is supposed to be overloaded by adapters pass
[docs] def reconnect(self, f=None): """ Defines: `self.connection` and `self.cursor` if `self.pool_size>0` it will try pull the connection from the pool if the connection is not active (closed by db server) it will loop if not `self.pool_size` or no active connections in pool makes a new one """ if getattr(self, 'connection', None) is not None: return if f is None: f = self.connector # if not hasattr(self, "driver") or self.driver is None: # LOGGER.debug("Skipping connection since there's no driver") # return if not self.pool_size: self.connection = f() self.cursor = self.connection.cursor() else: uri = self.uri POOLS = ConnectionPool.POOLS while True: GLOBAL_LOCKER.acquire() if uri not in POOLS: POOLS[uri] = [] if POOLS[uri]: self.connection = POOLS[uri].pop() GLOBAL_LOCKER.release() self.cursor = self.connection.cursor() try: if self.check_active_connection: self.execute_test_query() break except: pass else: GLOBAL_LOCKER.release() self.connection = f() self.cursor = self.connection.cursor() break self.after_connection_hook()