Merge branch 'zope-fixes' into devel

This commit is contained in:
Daniele Varrazzo 2012-12-04 00:34:48 +00:00
commit 170636d46d
7 changed files with 175 additions and 13 deletions

3
NEWS
View File

@ -27,7 +27,8 @@ What's new in psycopg 2.4.6
(ticket #113).
- 'register_hstore()', 'register_composite()', 'tpc_recover()' work with
RealDictConnection and Cursor (ticket #114).
- Fixed broken pool for Zope (tickets #123, #125).
- Fixed broken pool for Zope and connections re-init across ZSQL methods
in the same request (tickets #123, #125, #142).
- connect() raises an exception instead of swallowing keyword arguments
when a connection string is specified as well (ticket #131).
- Discard any result produced by 'executemany()' (ticket #133).

View File

@ -16,7 +16,7 @@
# their work without bothering about the module dependencies.
ALLOWED_PSYCOPG_VERSIONS = ('2.4-beta1', '2.4-beta2', '2.4', '2.4.1', '2.4.2', '2.4.3', '2.4.4', '2.4.5')
ALLOWED_PSYCOPG_VERSIONS = ('2.4', '2.4.1', '2.4.4', '2.4.5', '2.4.6')
import sys
import time

View File

@ -32,7 +32,7 @@ from psycopg2 import NUMBER, STRING, ROWID, DATETIME
# the DB object, managing all the real query work
class DB(TM, dbi_db.DB):
_p_oid = _p_changed = _registered = None
def __init__(self, dsn, tilevel, typecasts, enc='utf-8'):
@ -46,13 +46,18 @@ class DB(TM, dbi_db.DB):
self.failures = 0
self.calls = 0
self.make_mappings()
def getconn(self, init=True):
# if init is False we are trying to get hold on an already existing
# connection, so we avoid to (re)initialize it risking errors.
conn = pool.getconn(self.dsn)
if init:
conn.set_isolation_level(int(self.tilevel))
# use set_session where available as in these versions
# set_isolation_level generates an extra query.
if psycopg2.__version__ >= '2.4.2':
conn.set_session(isolation_level=int(self.tilevel))
else:
conn.set_isolation_level(int(self.tilevel))
conn.set_client_encoding(self.encoding)
for tc in self.typecasts:
register_type(tc, conn)
@ -64,9 +69,9 @@ class DB(TM, dbi_db.DB):
except AttributeError:
pass
pool.putconn(self.dsn, conn, close)
def getcursor(self):
conn = self.getconn()
conn = self.getconn(False)
return conn.cursor()
def _finish(self, *ignored):
@ -76,7 +81,7 @@ class DB(TM, dbi_db.DB):
self.putconn()
except AttributeError:
pass
def _abort(self, *ignored):
try:
conn = self.getconn(False)
@ -90,7 +95,7 @@ class DB(TM, dbi_db.DB):
# then get and immediately release a connection
self.getconn()
self.putconn()
def close(self):
# FIXME: if this connection is closed we flush all the pool associated
# with the current DSN; does this makes sense?

View File

@ -78,8 +78,10 @@ or DSN for short) is a string... (TODO: finish docs)
</td>
<td align="left" valign="top">
<select name="tilevel:int">
<option value="4">Read uncommitted</option>
<option value="1">Read committed</option>
<option value="2" selected="YES">Serializable</option>
<option value="2" selected="YES">Repeatable read</option>
<option value="3">Serializable</option>
</select>
</td>
</tr>

View File

@ -44,11 +44,17 @@
</td>
<td align="left" valign="top">
<select name="tilevel:int">
<option value="4"
<dtml-if expr="tilevel==4">selected="YES"</dtml-if>>
Read uncommitted</option>
<option value="1"
<dtml-if expr="tilevel==1">selected="YES"</dtml-if>>
Read committed</option>
<option value="2"
<dtml-if expr="tilevel==2">selected="YES"</dtml-if>>
Repeatable read</option>
<option value="3"
<dtml-if expr="tilevel==3">selected="YES"</dtml-if>>
Serializable</option>
</select>
</td>

View File

@ -19,7 +19,151 @@
# ZPsycopgDA code in db.py.
import threading
import psycopg2.pool
import psycopg2
from psycopg2.pool import PoolError
class AbstractConnectionPool(object):
"""Generic key-based pooling code."""
def __init__(self, minconn, maxconn, *args, **kwargs):
"""Initialize the connection pool.
New 'minconn' connections are created immediately calling 'connfunc'
with given parameters. The connection pool will support a maximum of
about 'maxconn' connections.
"""
self.minconn = minconn
self.maxconn = maxconn
self.closed = False
self._args = args
self._kwargs = kwargs
self._pool = []
self._used = {}
self._rused = {} # id(conn) -> key map
self._keys = 0
for i in range(self.minconn):
self._connect()
def _connect(self, key=None):
"""Create a new connection and assign it to 'key' if not None."""
conn = psycopg2.connect(*self._args, **self._kwargs)
if key is not None:
self._used[key] = conn
self._rused[id(conn)] = key
else:
self._pool.append(conn)
return conn
def _getkey(self):
"""Return a new unique key."""
self._keys += 1
return self._keys
def _getconn(self, key=None):
"""Get a free connection and assign it to 'key' if not None."""
if self.closed: raise PoolError("connection pool is closed")
if key is None: key = self._getkey()
if key in self._used:
return self._used[key]
if self._pool:
self._used[key] = conn = self._pool.pop()
self._rused[id(conn)] = key
return conn
else:
if len(self._used) == self.maxconn:
raise PoolError("connection pool exausted")
return self._connect(key)
def _putconn(self, conn, key=None, close=False):
"""Put away a connection."""
if self.closed: raise PoolError("connection pool is closed")
if key is None: key = self._rused[id(conn)]
if not key:
raise PoolError("trying to put unkeyed connection")
if len(self._pool) < self.minconn and not close:
self._pool.append(conn)
else:
conn.close()
# here we check for the presence of key because it can happen that a
# thread tries to put back a connection after a call to close
if not self.closed or key in self._used:
del self._used[key]
del self._rused[id(conn)]
def _closeall(self):
"""Close all connections.
Note that this can lead to some code fail badly when trying to use
an already closed connection. If you call .closeall() make sure
your code can deal with it.
"""
if self.closed: raise PoolError("connection pool is closed")
for conn in self._pool + list(self._used.values()):
try:
conn.close()
except:
pass
self.closed = True
class PersistentConnectionPool(AbstractConnectionPool):
"""A pool that assigns persistent connections to different threads.
Note that this connection pool generates by itself the required keys
using the current thread id. This means that until a thread puts away
a connection it will always get the same connection object by successive
`!getconn()` calls. This also means that a thread can't use more than one
single connection from the pool.
"""
def __init__(self, minconn, maxconn, *args, **kwargs):
"""Initialize the threading lock."""
import threading
AbstractConnectionPool.__init__(
self, minconn, maxconn, *args, **kwargs)
self._lock = threading.Lock()
# we we'll need the thread module, to determine thread ids, so we
# import it here and copy it in an instance variable
import thread
self.__thread = thread
def getconn(self):
"""Generate thread id and return a connection."""
key = self.__thread.get_ident()
self._lock.acquire()
try:
return self._getconn(key)
finally:
self._lock.release()
def putconn(self, conn=None, close=False):
"""Put away an unused connection."""
key = self.__thread.get_ident()
self._lock.acquire()
try:
if not conn: conn = self._used[key]
self._putconn(conn, key, close)
finally:
self._lock.release()
def closeall(self):
"""Close all connections (even the one currently in use.)"""
self._lock.acquire()
try:
self._closeall()
finally:
self._lock.release()
_connections_pool = {}
_connections_lock = threading.Lock()
@ -29,7 +173,7 @@ def getpool(dsn, create=True):
try:
if not _connections_pool.has_key(dsn) and create:
_connections_pool[dsn] = \
psycopg2.pool.PersistentConnectionPool(4, 200, dsn)
PersistentConnectionPool(4, 200, dsn)
finally:
_connections_lock.release()
return _connections_pool[dsn]
@ -41,7 +185,7 @@ def flushpool(dsn):
del _connections_pool[dsn]
finally:
_connections_lock.release()
def getconn(dsn, create=True):
return getpool(dsn, create=create).getconn()

View File

@ -217,6 +217,10 @@ class PersistentConnectionPool(AbstractConnectionPool):
def __init__(self, minconn, maxconn, *args, **kwargs):
"""Initialize the threading lock."""
import warnings
warnings.warn("deprecated: use ZPsycopgDA.pool implementation",
DeprecationWarning)
import threading
AbstractConnectionPool.__init__(
self, minconn, maxconn, *args, **kwargs)