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			693 lines
		
	
	
	
		
			25 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
			
		
		
	
	
			693 lines
		
	
	
	
		
			25 KiB
		
	
	
	
		
			Python
		
	
	
	
	
	
| #-----------------------------------------------------------------------
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| #
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| # Copyright (C) 2000, 2001 by Autonomous Zone Industries
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| # Copyright (C) 2002 Gregory P. Smith
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| #
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| # License:      This is free software.  You may use this software for any
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| #               purpose including modification/redistribution, so long as
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| #               this header remains intact and that you do not claim any
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| #               rights of ownership or authorship of this software.  This
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| #               software has been tested, but no warranty is expressed or
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| #               implied.
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| #
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| #   --  Gregory P. Smith <greg@electricrain.com>
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| 
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| # This provides a simple database table interface built on top of
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| # the Python BerkeleyDB 3 interface.
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| #
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| _cvsid = '$Id$'
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| 
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| import re
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| import sys
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| import copy
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| import xdrlib
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| import random
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| from types import ListType, StringType
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| import cPickle as pickle
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| 
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| try:
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|     # For Pythons w/distutils pybsddb
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|     from bsddb3.db import *
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| except ImportError:
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|     # For Python 2.3
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|     from bsddb.db import *
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| 
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| 
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| class TableDBError(StandardError):
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|     pass
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| class TableAlreadyExists(TableDBError):
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|     pass
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| 
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| 
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| class Cond:
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|     """This condition matches everything"""
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|     def __call__(self, s):
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|         return 1
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| 
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| class ExactCond(Cond):
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|     """Acts as an exact match condition function"""
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|     def __init__(self, strtomatch):
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|         self.strtomatch = strtomatch
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|     def __call__(self, s):
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|         return s == self.strtomatch
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| 
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| class PrefixCond(Cond):
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|     """Acts as a condition function for matching a string prefix"""
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|     def __init__(self, prefix):
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|         self.prefix = prefix
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|     def __call__(self, s):
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|         return s[:len(self.prefix)] == self.prefix
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| 
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| class PostfixCond(Cond):
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|     """Acts as a condition function for matching a string postfix"""
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|     def __init__(self, postfix):
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|         self.postfix = postfix
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|     def __call__(self, s):
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|         return s[-len(self.postfix):] == self.postfix
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| 
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| class LikeCond(Cond):
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|     """
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|     Acts as a function that will match using an SQL 'LIKE' style
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|     string.  Case insensitive and % signs are wild cards.
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|     This isn't perfect but it should work for the simple common cases.
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|     """
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|     def __init__(self, likestr, re_flags=re.IGNORECASE):
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|         # escape python re characters
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|         chars_to_escape = '.*+()[]?'
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|         for char in chars_to_escape :
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|             likestr = likestr.replace(char, '\\'+char)
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|         # convert %s to wildcards
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|         self.likestr = likestr.replace('%', '.*')
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|         self.re = re.compile('^'+self.likestr+'$', re_flags)
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|     def __call__(self, s):
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|         return self.re.match(s)
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| 
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| #
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| # keys used to store database metadata
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| #
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| _table_names_key = '__TABLE_NAMES__'  # list of the tables in this db
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| _columns = '._COLUMNS__'  # table_name+this key contains a list of columns
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| 
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| def _columns_key(table):
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|     return table + _columns
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| 
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| #
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| # these keys are found within table sub databases
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| #
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| _data =  '._DATA_.'  # this+column+this+rowid key contains table data
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| _rowid = '._ROWID_.' # this+rowid+this key contains a unique entry for each
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|                      # row in the table.  (no data is stored)
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| _rowid_str_len = 8   # length in bytes of the unique rowid strings
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| 
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| def _data_key(table, col, rowid):
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|     return table + _data + col + _data + rowid
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| 
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| def _search_col_data_key(table, col):
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|     return table + _data + col + _data
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| 
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| def _search_all_data_key(table):
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|     return table + _data
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| 
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| def _rowid_key(table, rowid):
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|     return table + _rowid + rowid + _rowid
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| 
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| def _search_rowid_key(table):
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|     return table + _rowid
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| 
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| def contains_metastrings(s) :
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|     """Verify that the given string does not contain any
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|     metadata strings that might interfere with dbtables database operation.
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|     """
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|     if (s.find(_table_names_key) >= 0 or
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|         s.find(_columns) >= 0 or
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|         s.find(_data) >= 0 or
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|         s.find(_rowid) >= 0):
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|         # Then
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|         return 1
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|     else:
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|         return 0
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| 
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| 
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| class bsdTableDB :
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|     def __init__(self, filename, dbhome, create=0, truncate=0, mode=0600,
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|                  recover=0, dbflags=0):
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|         """bsdTableDB.open(filename, dbhome, create=0, truncate=0, mode=0600)
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|         Open database name in the dbhome BerkeleyDB directory.
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|         Use keyword arguments when calling this constructor.
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|         """
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|         self.db = None
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|         myflags = DB_THREAD
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|         if create:
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|             myflags |= DB_CREATE
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|         flagsforenv = (DB_INIT_MPOOL | DB_INIT_LOCK | DB_INIT_LOG |
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|                        DB_INIT_TXN | dbflags)
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|         # DB_AUTO_COMMIT isn't a valid flag for env.open()
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|         try:
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|             dbflags |= DB_AUTO_COMMIT
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|         except AttributeError:
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|             pass
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|         if recover:
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|             flagsforenv = flagsforenv | DB_RECOVER
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|         self.env = DBEnv()
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|         # enable auto deadlock avoidance
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|         self.env.set_lk_detect(DB_LOCK_DEFAULT)
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|         self.env.open(dbhome, myflags | flagsforenv)
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|         if truncate:
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|             myflags |= DB_TRUNCATE
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|         self.db = DB(self.env)
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|         # this code relies on DBCursor.set* methods to raise exceptions
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|         # rather than returning None
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|         self.db.set_get_returns_none(1)
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|         # allow duplicate entries [warning: be careful w/ metadata]
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|         self.db.set_flags(DB_DUP)
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|         self.db.open(filename, DB_BTREE, dbflags | myflags, mode)
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|         self.dbfilename = filename
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|         # Initialize the table names list if this is a new database
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|         txn = self.env.txn_begin()
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|         try:
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|             if not self.db.has_key(_table_names_key, txn):
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|                 self.db.put(_table_names_key, pickle.dumps([], 1), txn=txn)
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|         # Yes, bare except
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|         except:
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|             txn.abort()
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|             raise
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|         else:
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|             txn.commit()
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|         # TODO verify more of the database's metadata?
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|         self.__tablecolumns = {}
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| 
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|     def __del__(self):
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|         self.close()
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| 
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|     def close(self):
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|         if self.db is not None:
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|             self.db.close()
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|             self.db = None
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|         if self.env is not None:
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|             self.env.close()
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|             self.env = None
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| 
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|     def checkpoint(self, mins=0):
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|         try:
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|             self.env.txn_checkpoint(mins)
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|         except DBIncompleteError:
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|             pass
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| 
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|     def sync(self):
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|         try:
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|             self.db.sync()
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|         except DBIncompleteError:
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|             pass
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| 
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|     def _db_print(self) :
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|         """Print the database to stdout for debugging"""
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|         print "******** Printing raw database for debugging ********"
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|         cur = self.db.cursor()
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|         try:
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|             key, data = cur.first()
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|             while 1:
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|                 print repr({key: data})
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|                 next = cur.next()
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|                 if next:
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|                     key, data = next
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|                 else:
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|                     cur.close()
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|                     return
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|         except DBNotFoundError:
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|             cur.close()
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| 
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| 
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|     def CreateTable(self, table, columns):
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|         """CreateTable(table, columns) - Create a new table in the database
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|         raises TableDBError if it already exists or for other DB errors.
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|         """
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|         assert isinstance(columns, ListType)
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|         txn = None
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|         try:
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|             # checking sanity of the table and column names here on
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|             # table creation will prevent problems elsewhere.
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|             if contains_metastrings(table):
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|                 raise ValueError(
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|                     "bad table name: contains reserved metastrings")
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|             for column in columns :
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|                 if contains_metastrings(column):
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|                     raise ValueError(
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|                         "bad column name: contains reserved metastrings")
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| 
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|             columnlist_key = _columns_key(table)
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|             if self.db.has_key(columnlist_key):
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|                 raise TableAlreadyExists, "table already exists"
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| 
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|             txn = self.env.txn_begin()
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|             # store the table's column info
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|             self.db.put(columnlist_key, pickle.dumps(columns, 1), txn=txn)
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| 
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|             # add the table name to the tablelist
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|             tablelist = pickle.loads(self.db.get(_table_names_key, txn=txn,
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|                                                  flags=DB_RMW))
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|             tablelist.append(table)
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|             # delete 1st, in case we opened with DB_DUP
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|             self.db.delete(_table_names_key, txn)
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|             self.db.put(_table_names_key, pickle.dumps(tablelist, 1), txn=txn)
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| 
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|             txn.commit()
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|             txn = None
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|         except DBError, dberror:
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|             if txn:
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|                 txn.abort()
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|             raise TableDBError, dberror[1]
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| 
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| 
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|     def ListTableColumns(self, table):
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|         """Return a list of columns in the given table.
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|         [] if the table doesn't exist.
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|         """
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|         assert isinstance(table, StringType)
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|         if contains_metastrings(table):
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|             raise ValueError, "bad table name: contains reserved metastrings"
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| 
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|         columnlist_key = _columns_key(table)
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|         if not self.db.has_key(columnlist_key):
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|             return []
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|         pickledcolumnlist = self.db.get(columnlist_key)
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|         if pickledcolumnlist:
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|             return pickle.loads(pickledcolumnlist)
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|         else:
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|             return []
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| 
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|     def ListTables(self):
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|         """Return a list of tables in this database."""
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|         pickledtablelist = self.db.get(_table_names_key)
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|         if pickledtablelist:
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|             return pickle.loads(pickledtablelist)
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|         else:
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|             return []
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| 
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|     def CreateOrExtendTable(self, table, columns):
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|         """CreateOrExtendTable(table, columns)
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| 
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|         - Create a new table in the database.
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|         If a table of this name already exists, extend it to have any
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|         additional columns present in the given list as well as
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|         all of its current columns.
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|         """
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|         assert isinstance(columns, ListType)
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|         try:
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|             self.CreateTable(table, columns)
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|         except TableAlreadyExists:
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|             # the table already existed, add any new columns
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|             txn = None
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|             try:
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|                 columnlist_key = _columns_key(table)
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|                 txn = self.env.txn_begin()
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| 
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|                 # load the current column list
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|                 oldcolumnlist = pickle.loads(
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|                     self.db.get(columnlist_key, txn=txn, flags=DB_RMW))
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|                 # create a hash table for fast lookups of column names in the
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|                 # loop below
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|                 oldcolumnhash = {}
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|                 for c in oldcolumnlist:
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|                     oldcolumnhash[c] = c
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| 
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|                 # create a new column list containing both the old and new
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|                 # column names
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|                 newcolumnlist = copy.copy(oldcolumnlist)
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|                 for c in columns:
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|                     if not oldcolumnhash.has_key(c):
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|                         newcolumnlist.append(c)
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| 
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|                 # store the table's new extended column list
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|                 if newcolumnlist != oldcolumnlist :
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|                     # delete the old one first since we opened with DB_DUP
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|                     self.db.delete(columnlist_key, txn)
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|                     self.db.put(columnlist_key,
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|                                 pickle.dumps(newcolumnlist, 1),
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|                                 txn=txn)
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| 
 | |
|                 txn.commit()
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|                 txn = None
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| 
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|                 self.__load_column_info(table)
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|             except DBError, dberror:
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|                 if txn:
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|                     txn.abort()
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|                 raise TableDBError, dberror[1]
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| 
 | |
| 
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|     def __load_column_info(self, table) :
 | |
|         """initialize the self.__tablecolumns dict"""
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|         # check the column names
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|         try:
 | |
|             tcolpickles = self.db.get(_columns_key(table))
 | |
|         except DBNotFoundError:
 | |
|             raise TableDBError, "unknown table: %r" % (table,)
 | |
|         if not tcolpickles:
 | |
|             raise TableDBError, "unknown table: %r" % (table,)
 | |
|         self.__tablecolumns[table] = pickle.loads(tcolpickles)
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| 
 | |
|     def __new_rowid(self, table, txn) :
 | |
|         """Create a new unique row identifier"""
 | |
|         unique = 0
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|         while not unique:
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|             # Generate a random 64-bit row ID string
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|             # (note: this code has <64 bits of randomness
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|             # but it's plenty for our database id needs!)
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|             p = xdrlib.Packer()
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|             p.pack_int(int(random.random()*2147483647))
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|             p.pack_int(int(random.random()*2147483647))
 | |
|             newid = p.get_buffer()
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| 
 | |
|             # Guarantee uniqueness by adding this key to the database
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|             try:
 | |
|                 self.db.put(_rowid_key(table, newid), None, txn=txn,
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|                             flags=DB_NOOVERWRITE)
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|             except DBKeyExistError:
 | |
|                 pass
 | |
|             else:
 | |
|                 unique = 1
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| 
 | |
|         return newid
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| 
 | |
| 
 | |
|     def Insert(self, table, rowdict) :
 | |
|         """Insert(table, datadict) - Insert a new row into the table
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|         using the keys+values from rowdict as the column values.
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|         """
 | |
|         txn = None
 | |
|         try:
 | |
|             if not self.db.has_key(_columns_key(table)):
 | |
|                 raise TableDBError, "unknown table"
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| 
 | |
|             # check the validity of each column name
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|             if not self.__tablecolumns.has_key(table):
 | |
|                 self.__load_column_info(table)
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|             for column in rowdict.keys() :
 | |
|                 if not self.__tablecolumns[table].count(column):
 | |
|                     raise TableDBError, "unknown column: %r" % (column,)
 | |
| 
 | |
|             # get a unique row identifier for this row
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|             txn = self.env.txn_begin()
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|             rowid = self.__new_rowid(table, txn=txn)
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| 
 | |
|             # insert the row values into the table database
 | |
|             for column, dataitem in rowdict.items():
 | |
|                 # store the value
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|                 self.db.put(_data_key(table, column, rowid), dataitem, txn=txn)
 | |
| 
 | |
|             txn.commit()
 | |
|             txn = None
 | |
| 
 | |
|         except DBError, dberror:
 | |
|             # WIBNI we could just abort the txn and re-raise the exception?
 | |
|             # But no, because TableDBError is not related to DBError via
 | |
|             # inheritance, so it would be backwards incompatible.  Do the next
 | |
|             # best thing.
 | |
|             info = sys.exc_info()
 | |
|             if txn:
 | |
|                 txn.abort()
 | |
|                 self.db.delete(_rowid_key(table, rowid))
 | |
|             raise TableDBError, dberror[1], info[2]
 | |
| 
 | |
| 
 | |
|     def Modify(self, table, conditions={}, mappings={}):
 | |
|         """Modify(table, conditions) - Modify in rows matching 'conditions'
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|         using mapping functions in 'mappings'
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|         * conditions is a dictionary keyed on column names
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|         containing condition functions expecting the data string as an
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|         argument and returning a boolean.
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|         * mappings is a dictionary keyed on column names containint condition
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|         functions expecting the data string as an argument and returning the
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|         new string for that column.
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|         """
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|         try:
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|             matching_rowids = self.__Select(table, [], conditions)
 | |
| 
 | |
|             # modify only requested columns
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|             columns = mappings.keys()
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|             for rowid in matching_rowids.keys():
 | |
|                 txn = None
 | |
|                 try:
 | |
|                     for column in columns:
 | |
|                         txn = self.env.txn_begin()
 | |
|                         # modify the requested column
 | |
|                         try:
 | |
|                             dataitem = self.db.get(
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|                                 _data_key(table, column, rowid),
 | |
|                                 txn)
 | |
|                             self.db.delete(
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|                                 _data_key(table, column, rowid),
 | |
|                                 txn)
 | |
|                         except DBNotFoundError:
 | |
|                              # XXXXXXX row key somehow didn't exist, assume no
 | |
|                              # error
 | |
|                             dataitem = None
 | |
|                         dataitem = mappings[column](dataitem)
 | |
|                         if dataitem <> None:
 | |
|                             self.db.put(
 | |
|                                 _data_key(table, column, rowid),
 | |
|                                 dataitem, txn=txn)
 | |
|                         txn.commit()
 | |
|                         txn = None
 | |
| 
 | |
|                 except DBError, dberror:
 | |
|                     if txn:
 | |
|                         txn.abort()
 | |
|                     raise
 | |
| 
 | |
|         except DBError, dberror:
 | |
|             raise TableDBError, dberror[1]
 | |
| 
 | |
|     def Delete(self, table, conditions={}):
 | |
|         """Delete(table, conditions) - Delete items matching the given
 | |
|         conditions from the table.
 | |
|         * conditions is a dictionary keyed on column names
 | |
|         containing condition functions expecting the data string as an
 | |
|         argument and returning a boolean.
 | |
|         """
 | |
|         try:
 | |
|             matching_rowids = self.__Select(table, [], conditions)
 | |
| 
 | |
|             # delete row data from all columns
 | |
|             columns = self.__tablecolumns[table]
 | |
|             for rowid in matching_rowids.keys():
 | |
|                 txn = None
 | |
|                 try:
 | |
|                     txn = self.env.txn_begin()
 | |
|                     for column in columns:
 | |
|                         # delete the data key
 | |
|                         try:
 | |
|                             self.db.delete(_data_key(table, column, rowid),
 | |
|                                            txn)
 | |
|                         except DBNotFoundError:
 | |
|                             # XXXXXXX column may not exist, assume no error
 | |
|                             pass
 | |
| 
 | |
|                     try:
 | |
|                         self.db.delete(_rowid_key(table, rowid), txn)
 | |
|                     except DBNotFoundError:
 | |
|                         # XXXXXXX row key somehow didn't exist, assume no error
 | |
|                         pass
 | |
|                     txn.commit()
 | |
|                     txn = None
 | |
|                 except DBError, dberror:
 | |
|                     if txn:
 | |
|                         txn.abort()
 | |
|                     raise
 | |
|         except DBError, dberror:
 | |
|             raise TableDBError, dberror[1]
 | |
| 
 | |
| 
 | |
|     def Select(self, table, columns, conditions={}):
 | |
|         """Select(table, conditions) - retrieve specific row data
 | |
|         Returns a list of row column->value mapping dictionaries.
 | |
|         * columns is a list of which column data to return.  If
 | |
|           columns is None, all columns will be returned.
 | |
|         * conditions is a dictionary keyed on column names
 | |
|           containing callable conditions expecting the data string as an
 | |
|           argument and returning a boolean.
 | |
|         """
 | |
|         try:
 | |
|             if not self.__tablecolumns.has_key(table):
 | |
|                 self.__load_column_info(table)
 | |
|             if columns is None:
 | |
|                 columns = self.__tablecolumns[table]
 | |
|             matching_rowids = self.__Select(table, columns, conditions)
 | |
|         except DBError, dberror:
 | |
|             raise TableDBError, dberror[1]
 | |
|         # return the matches as a list of dictionaries
 | |
|         return matching_rowids.values()
 | |
| 
 | |
| 
 | |
|     def __Select(self, table, columns, conditions):
 | |
|         """__Select() - Used to implement Select and Delete (above)
 | |
|         Returns a dictionary keyed on rowids containing dicts
 | |
|         holding the row data for columns listed in the columns param
 | |
|         that match the given conditions.
 | |
|         * conditions is a dictionary keyed on column names
 | |
|         containing callable conditions expecting the data string as an
 | |
|         argument and returning a boolean.
 | |
|         """
 | |
|         # check the validity of each column name
 | |
|         if not self.__tablecolumns.has_key(table):
 | |
|             self.__load_column_info(table)
 | |
|         if columns is None:
 | |
|             columns = self.tablecolumns[table]
 | |
|         for column in (columns + conditions.keys()):
 | |
|             if not self.__tablecolumns[table].count(column):
 | |
|                 raise TableDBError, "unknown column: %r" % (column,)
 | |
| 
 | |
|         # keyed on rows that match so far, containings dicts keyed on
 | |
|         # column names containing the data for that row and column.
 | |
|         matching_rowids = {}
 | |
|         # keys are rowids that do not match
 | |
|         rejected_rowids = {}
 | |
| 
 | |
|         # attempt to sort the conditions in such a way as to minimize full
 | |
|         # column lookups
 | |
|         def cmp_conditions(atuple, btuple):
 | |
|             a = atuple[1]
 | |
|             b = btuple[1]
 | |
|             if type(a) is type(b):
 | |
|                 if isinstance(a, PrefixCond) and isinstance(b, PrefixCond):
 | |
|                     # longest prefix first
 | |
|                     return cmp(len(b.prefix), len(a.prefix))
 | |
|                 if isinstance(a, LikeCond) and isinstance(b, LikeCond):
 | |
|                     # longest likestr first
 | |
|                     return cmp(len(b.likestr), len(a.likestr))
 | |
|                 return 0
 | |
|             if isinstance(a, ExactCond):
 | |
|                 return -1
 | |
|             if isinstance(b, ExactCond):
 | |
|                 return 1
 | |
|             if isinstance(a, PrefixCond):
 | |
|                 return -1
 | |
|             if isinstance(b, PrefixCond):
 | |
|                 return 1
 | |
|             # leave all unknown condition callables alone as equals
 | |
|             return 0
 | |
| 
 | |
|         conditionlist = conditions.items()
 | |
|         conditionlist.sort(cmp_conditions)
 | |
| 
 | |
|         # Apply conditions to column data to find what we want
 | |
|         cur = self.db.cursor()
 | |
|         column_num = -1
 | |
|         for column, condition in conditionlist:
 | |
|             column_num = column_num + 1
 | |
|             searchkey = _search_col_data_key(table, column)
 | |
|             # speedup: don't linear search columns within loop
 | |
|             if column in columns:
 | |
|                 savethiscolumndata = 1  # save the data for return
 | |
|             else:
 | |
|                 savethiscolumndata = 0  # data only used for selection
 | |
| 
 | |
|             try:
 | |
|                 key, data = cur.set_range(searchkey)
 | |
|                 while key[:len(searchkey)] == searchkey:
 | |
|                     # extract the rowid from the key
 | |
|                     rowid = key[-_rowid_str_len:]
 | |
| 
 | |
|                     if not rejected_rowids.has_key(rowid):
 | |
|                         # if no condition was specified or the condition
 | |
|                         # succeeds, add row to our match list.
 | |
|                         if not condition or condition(data):
 | |
|                             if not matching_rowids.has_key(rowid):
 | |
|                                 matching_rowids[rowid] = {}
 | |
|                             if savethiscolumndata:
 | |
|                                 matching_rowids[rowid][column] = data
 | |
|                         else:
 | |
|                             if matching_rowids.has_key(rowid):
 | |
|                                 del matching_rowids[rowid]
 | |
|                             rejected_rowids[rowid] = rowid
 | |
| 
 | |
|                     key, data = cur.next()
 | |
| 
 | |
|             except DBError, dberror:
 | |
|                 if dberror[0] != DB_NOTFOUND:
 | |
|                     raise
 | |
|                 continue
 | |
| 
 | |
|         cur.close()
 | |
| 
 | |
|         # we're done selecting rows, garbage collect the reject list
 | |
|         del rejected_rowids
 | |
| 
 | |
|         # extract any remaining desired column data from the
 | |
|         # database for the matching rows.
 | |
|         if len(columns) > 0:
 | |
|             for rowid, rowdata in matching_rowids.items():
 | |
|                 for column in columns:
 | |
|                     if rowdata.has_key(column):
 | |
|                         continue
 | |
|                     try:
 | |
|                         rowdata[column] = self.db.get(
 | |
|                             _data_key(table, column, rowid))
 | |
|                     except DBError, dberror:
 | |
|                         if dberror[0] != DB_NOTFOUND:
 | |
|                             raise
 | |
|                         rowdata[column] = None
 | |
| 
 | |
|         # return the matches
 | |
|         return matching_rowids
 | |
| 
 | |
| 
 | |
|     def Drop(self, table):
 | |
|         """Remove an entire table from the database"""
 | |
|         txn = None
 | |
|         try:
 | |
|             txn = self.env.txn_begin()
 | |
| 
 | |
|             # delete the column list
 | |
|             self.db.delete(_columns_key(table), txn)
 | |
| 
 | |
|             cur = self.db.cursor(txn)
 | |
| 
 | |
|             # delete all keys containing this tables column and row info
 | |
|             table_key = _search_all_data_key(table)
 | |
|             while 1:
 | |
|                 try:
 | |
|                     key, data = cur.set_range(table_key)
 | |
|                 except DBNotFoundError:
 | |
|                     break
 | |
|                 # only delete items in this table
 | |
|                 if key[:len(table_key)] != table_key:
 | |
|                     break
 | |
|                 cur.delete()
 | |
| 
 | |
|             # delete all rowids used by this table
 | |
|             table_key = _search_rowid_key(table)
 | |
|             while 1:
 | |
|                 try:
 | |
|                     key, data = cur.set_range(table_key)
 | |
|                 except DBNotFoundError:
 | |
|                     break
 | |
|                 # only delete items in this table
 | |
|                 if key[:len(table_key)] != table_key:
 | |
|                     break
 | |
|                 cur.delete()
 | |
| 
 | |
|             cur.close()
 | |
| 
 | |
|             # delete the tablename from the table name list
 | |
|             tablelist = pickle.loads(
 | |
|                 self.db.get(_table_names_key, txn=txn, flags=DB_RMW))
 | |
|             try:
 | |
|                 tablelist.remove(table)
 | |
|             except ValueError:
 | |
|                 # hmm, it wasn't there, oh well, that's what we want.
 | |
|                 pass
 | |
|             # delete 1st, incase we opened with DB_DUP
 | |
|             self.db.delete(_table_names_key, txn)
 | |
|             self.db.put(_table_names_key, pickle.dumps(tablelist, 1), txn=txn)
 | |
| 
 | |
|             txn.commit()
 | |
|             txn = None
 | |
| 
 | |
|             if self.__tablecolumns.has_key(table):
 | |
|                 del self.__tablecolumns[table]
 | |
| 
 | |
|         except DBError, dberror:
 | |
|             if txn:
 | |
|                 txn.abort()
 | |
|             raise TableDBError, dberror[1]
 | 
