implement global lock by locking hands table

This commit is contained in:
sqlcoder 2009-05-31 21:59:01 +01:00
parent be61b2d253
commit 5b96769de3
2 changed files with 55 additions and 24 deletions

View File

@ -174,7 +174,7 @@ class fpdb:
def dia_load_profile(self, widget, data=None): def dia_load_profile(self, widget, data=None):
"""Dialogue to select a file to load a profile from""" """Dialogue to select a file to load a profile from"""
self.obtain_global_lock() if self.obtain_global_lock():
chooser = gtk.FileChooserDialog(title="Please select a profile file to load", chooser = gtk.FileChooserDialog(title="Please select a profile file to load",
action=gtk.FILE_CHOOSER_ACTION_OPEN, action=gtk.FILE_CHOOSER_ACTION_OPEN,
buttons=(gtk.STOCK_CANCEL,gtk.RESPONSE_CANCEL,gtk.STOCK_OPEN,gtk.RESPONSE_OK)) buttons=(gtk.STOCK_CANCEL,gtk.RESPONSE_CANCEL,gtk.STOCK_OPEN,gtk.RESPONSE_OK))
@ -190,7 +190,7 @@ class fpdb:
def dia_recreate_tables(self, widget, data=None): def dia_recreate_tables(self, widget, data=None):
"""Dialogue that asks user to confirm that he wants to delete and recreate the tables""" """Dialogue that asks user to confirm that he wants to delete and recreate the tables"""
self.obtain_global_lock() if self.obtain_global_lock():
dia_confirm = gtk.MessageDialog(parent=None, flags=0, type=gtk.MESSAGE_WARNING, dia_confirm = gtk.MessageDialog(parent=None, flags=0, type=gtk.MESSAGE_WARNING,
buttons=(gtk.BUTTONS_YES_NO), message_format="Confirm deleting and recreating tables") buttons=(gtk.BUTTONS_YES_NO), message_format="Confirm deleting and recreating tables")
@ -203,6 +203,7 @@ class fpdb:
self.db.recreate_tables() self.db.recreate_tables()
elif response == gtk.RESPONSE_NO: elif response == gtk.RESPONSE_NO:
print 'User cancelled recreating tables' print 'User cancelled recreating tables'
self.release_global_lock()
#end def dia_recreate_tables #end def dia_recreate_tables
def dia_regression_test(self, widget, data=None): def dia_regression_test(self, widget, data=None):
@ -371,7 +372,14 @@ class fpdb:
#end def not_implemented #end def not_implemented
def obtain_global_lock(self): def obtain_global_lock(self):
print "todo: implement obtain_global_lock (users: pls ignore this)" print "\nTaking global lock ..."
self.fdb_lock = fpdb_db.fpdb_db()
self.fdb_lock.connect(self.settings['db-backend'],
self.settings['db-host'],
self.settings['db-databaseName'],
self.settings['db-user'],
self.settings['db-password'])
return fpdb_simple.get_global_lock(self.fdb_lock)
#end def obtain_global_lock #end def obtain_global_lock
def quit(self, widget): def quit(self, widget):
@ -382,7 +390,9 @@ class fpdb:
#end def quit_cliecked #end def quit_cliecked
def release_global_lock(self): def release_global_lock(self):
print "todo: implement release_global_lock" self.fdb_lock.db.rollback()
self.fdb_lock.disconnect()
print "Global lock released."
#end def release_global_lock #end def release_global_lock
def tab_abbreviations(self, widget, data=None): def tab_abbreviations(self, widget, data=None):

View File

@ -367,6 +367,27 @@ def analyzeDB(fdb):
fdb.db.commit() fdb.db.commit()
#end def analyzeDB #end def analyzeDB
def get_global_lock(fdb):
if fdb.backend == MYSQL_INNODB:
try:
fdb.cursor.execute( "lock tables Hands write" )
except:
print "Error! failed to obtain global lock. Close all programs accessing " \
+ "database (including fpdb) and try again (%s)." \
% ( str(sys.exc_value).rstrip('\n'), )
return(False)
elif fdb.backend == PGSQL:
try:
fdb.cursor.execute( "lock table Hands in exclusive mode nowait" )
#print "... after lock table, status =", fdb.cursor.statusmessage
except:
print "Error! failed to obtain global lock. Close all programs accessing " \
+ "database (including fpdb) and try again (%s)." \
% ( str(sys.exc_value).rstrip('\n'), )
return(False)
return(True)
class DuplicateError(Exception): class DuplicateError(Exception):
def __init__(self, value): def __init__(self, value):
self.value = value self.value = value