skytools: seems psycopg2 isolation constants do change

Psycopg 2.4.2 moved them around.

Stop hard-coding them, instead import from psycopg2.externsions

Also have a symbol for repeatable read.

3 files changed, 24 insertions, 30 deletions

diff --git a/python/skytools/__init__.py b/python/skytools/__init__.py
index b2f1eae1..c424051d 100644
--- a/python/skytools/__init__.py
+++ b/python/skytools/__init__.py
@@ -35,6 +35,10 @@ _symbols = {
     # skytools.psycopgwrapper
     'connect_database': 'skytools.psycopgwrapper:connect_database',
     'DBError': 'skytools.psycopgwrapper:DBError',
+    'I_AUTOCOMMIT': 'skytools.psycopgwrapper:I_AUTOCOMMIT',
+    'I_READ_COMMITTED': 'skytools.psycopgwrapper:I_READ_COMMITTED',
+    'I_REPEATABLE_READ': 'skytools.psycopgwrapper:I_REPEATABLE_READ',
+    'I_SERIALIZABLE': 'skytools.psycopgwrapper:I_SERIALIZABLE',
     # skytools.querybuilder
     'PLPyQuery': 'skytools.querybuilder:PLPyQuery',
     'PLPyQueryBuilder': 'skytools.querybuilder:PLPyQueryBuilder',
@@ -69,9 +73,6 @@ _symbols = {
     'DBScript': 'skytools.scripting:DBScript',
     'signal_pidfile': 'skytools.scripting:signal_pidfile',
     'UsageError': 'skytools.scripting:UsageError',
-    'I_AUTOCOMMIT': 'skytools.scripting:I_AUTOCOMMIT',
-    'I_READ_COMMITTED': 'skytools.scripting:I_READ_COMMITTED',
-    'I_SERIALIZABLE': 'skytools.scripting:I_SERIALIZABLE',
     # skytools.skylog
     'getLogger': 'skytools.skylog:getLogger',
     # skytools.sockutil
diff --git a/python/skytools/psycopgwrapper.py b/python/skytools/psycopgwrapper.py
index 923b6f39..8c6d90b6 100644
--- a/python/skytools/psycopgwrapper.py
+++ b/python/skytools/psycopgwrapper.py
@@ -54,21 +54,25 @@ Plain .fetchall() / .fetchone() give exact same result.
 
 """
 
-# no exports
-__all__ = ['connect_database', 'DBError']
+__all__ = ['connect_database', 'DBError', 'I_AUTOCOMMIT', 'I_READ_COMMITTED',
+           'I_REPEATABLE_READ', 'I_SERIALIZABLE']
 
-##from psycopg2.psycopg1 import connect as _pgconnect
-# psycopg2.psycopg1.cursor is too backwards compatible,
-# to the point of avoiding optimized access.
-# only backwards compat thing we need is dict* methods
-
-import sys, socket
-import psycopg2.extensions, psycopg2.extras
-from psycopg2 import Error as DBError
+import sys
+import socket
+import psycopg2.extensions
+import psycopg2.extras
 import skytools
 
+from psycopg2 import Error as DBError
 from skytools.sockutil import set_tcp_keepalive
 
+
+I_AUTOCOMMIT = psycopg2.extensions.ISOLATION_LEVEL_AUTOCOMMIT
+I_READ_COMMITTED = psycopg2.extensions.ISOLATION_LEVEL_READ_COMMITTED
+I_REPEATABLE_READ = psycopg2.extensions.ISOLATION_LEVEL_REPEATABLE_READ
+I_SERIALIZABLE = psycopg2.extensions.ISOLATION_LEVEL_SERIALIZABLE
+
+
 class _CompatRow(psycopg2.extras.DictRow):
     """Make DictRow more dict-like."""
     __slots__ = ('_index',)
diff --git a/python/skytools/scripting.py b/python/skytools/scripting.py
index 558998c2..ad6a2fd6 100644
--- a/python/skytools/scripting.py
+++ b/python/skytools/scripting.py
@@ -18,7 +18,7 @@ except ImportError:
 __pychecker__ = 'no-badexcept'
 
 __all__ = ['BaseScript', 'signal_pidfile', 'UsageError', 'daemonize',
-            'DBScript', 'I_AUTOCOMMIT', 'I_READ_COMMITTED', 'I_SERIALIZABLE']
+            'DBScript']
 
 class UsageError(Exception):
     """User induced error."""
@@ -637,17 +637,6 @@ class BaseScript(object):
 #: how old connections need to be closed
 DEF_CONN_AGE = 20*60  # 20 min
 
-#: isolation level not set
-I_DEFAULT = -1
-
-#: isolation level constant for AUTOCOMMIT
-I_AUTOCOMMIT = 0
-#: isolation level constant for READ COMMITTED
-I_READ_COMMITTED = 1
-#: isolation level constant for SERIALIZABLE
-I_SERIALIZABLE = 2
-
-
 class DBScript(BaseScript):
     """Base class for database scripts.
 
@@ -708,7 +697,7 @@ class DBScript(BaseScript):
         elif params.get('autocommit', 0):
             params['isolation_level'] = 0
         elif not 'isolation_level' in params:
-            params['isolation_level'] = I_READ_COMMITTED
+            params['isolation_level'] = skytools.I_READ_COMMITTED
 
         if not 'max_age' in params:
             params['max_age'] = max_age
@@ -933,7 +922,7 @@ class DBCachedConn(object):
         self.conn_time = 0
         self.max_age = max_age
         self.autocommit = -1
-        self.isolation_level = I_DEFAULT
+        self.isolation_level = -1
         self.verbose = verbose
         self.setup_func = setup_func
         self.listen_channel_list = []
@@ -943,11 +932,11 @@ class DBCachedConn(object):
             return None
         return self.conn.cursor().fileno()
 
-    def get_connection(self, isolation_level = I_DEFAULT, listen_channel_list = []):
+    def get_connection(self, isolation_level = -1, listen_channel_list = []):
 
         # default isolation_level is READ COMMITTED
         if isolation_level < 0:
-            isolation_level = I_READ_COMMITTED
+            isolation_level = skytools.I_READ_COMMITTED
 
         # new conn?
         if not self.conn:
@@ -978,7 +967,7 @@ class DBCachedConn(object):
         for ch in new_clist:
             if ch not in self.listen_channel_list:
                 curs.execute("LISTEN %s" % skytools.quote_ident(ch))
-        if self.isolation_level != I_AUTOCOMMIT:
+        if self.isolation_level != skytools.I_AUTOCOMMIT:
             self.conn.commit()
         self.listen_channel_list = new_clist[:]