hotcopy depends on PySQLite 1.x

[pellatt@…]

I'm on the latest trunk, running on Windows 2003 Server, and get this stack trace:

Trac [<repopath>]> hotcopy \tr
Traceback (most recent call last):
  File "trac-admin", line 26, in ?
    run(*sys.argv[1:])
  File "C:\Program Files\Python23\Lib\site-packages\trac\scripts \admin.py",
 1085, in run
    tracadm.run()
  File "C:\Program Files\Python23\Lib\site-packages\trac\scripts \admin.py",
 82, in run
    self.cmdloop()
  File "C:\Program Files\Python23\lib\cmd.py", line 133, in cmdloop
    stop = self.onecmd(line)
  File "C:\Program Files\Python23\lib\cmd.py", line 210, in onecmd
    return func(arg)
  File "C:\Program Files\Python23\Lib\site-packages\trac\scripts \admin.py",
 1053, in do_hotcopy
    cnx.db.execute("BEGIN")
  File "C:\Program Files\Python23\Lib\site-packages\trac\db.py",  line 101,
getattr__
    return getattr(self.cnx, name)
  File "C:\Program Files\Python23\Lib\site-packages\trac\db.py",  line 101,
getattr__
    return getattr(self.cnx, name)
AttributeError: 'pysqlite2.dbapi2.Connection' object has no  attribute 'db'

Other trac admin commands seem to work fine, as does normal use of the wiki etc.

FYI - the other versions I have are clearilver 0.9.14, docutils 0.3.9, pysqlite 2.0.3, sqlite 3.2.5, svn 1.2.3.

Response from the mailing list was "This is a leftover from when we only supported SQLite, and only PySQLite 1.x. ".

[Christopher Lenz]

Better summary

[Christopher Lenz]

The following patch resolves this problem:

trac/scripts/admin.py

@@ -1050 +1050 @@
             return
         cnx = self.db_open()
         # Lock the database while copying files
-        cnx.db.execute("BEGIN")
-        print 'Hotcopying %s to %s ...' % (self.__env.path, dest),
+        cursor = cnx.cursor()
+        print 'Hotcopying %s to %s ...' % (self.__env.path, dest)
         try:
             shutil.copytree(self.__env.path, dest, symlinks=1)
             print 'OK'
         except Exception, err:
             print err
         # Unlock database
-        cnx.db.execute("ROLLBACK")
+        cnx.rollback()
 
 ## ---------------------------------------------------------------------------
 

However, I'm not sure whether this actually locks the database during hotcopy.

[Matthew Good]

Simply opening a cursor to the database doesn't lock it. Executing BEGIN in a pysqlite2 cursor doesn't seem to actually lock the database (though it confuses pysqlite2 since it tries to start transactions itself when you run a query that may update the database.

As far as I can tell the only way to lock the database with pysqlite2 is to execute an INSERT/UPDATE/DELETE statement. I suppose that one option would be to simply run an innocuous statement that wouldn't change anything, but would force it to lock the database:

update system set name = null where name is null

[Christopher Lenz]

Yeah, that's probably the best we can do here. I'll make that change.

[Christopher Lenz]

Fixed in [2263].