Source Code for Module orm2.debug

  1  #!/usr/bin/env python 
  2  # -*- coding: iso-8859-1 -*- 
  3   
  4  ##  This file is part of orm, The Object Relational Membrane Version 2. 
  5  ## 
  6  ##  Copyright 2002-2006 by Diedrich Vorberg <diedrich@tux4web.de> 
  7  ## 
  8  ##  All Rights Reserved 
  9  ## 
 10  ##  For more Information on orm see the README file. 
 11  ## 
 12  ##  This program is free software; you can redistribute it and/or modify 
 13  ##  it under the terms of the GNU General Public License as published by 
 14  ##  the Free Software Foundation; either version 2 of the License, or 
 15  ##  (at your option) any later version. 
 16  ## 
 17  ##  This program is distributed in the hope that it will be useful, 
 18  ##  but WITHOUT ANY WARRANTY; without even the implied warranty of 
 19  ##  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 20  ##  GNU General Public License for more details. 
 21  ## 
 22  ##  You should have received a copy of the GNU General Public License 
 23  ##  along with this program; if not, write to the Free Software 
 24  ##  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA 
 25  ## 
 26  ##  I have added a copy of the GPL in the file COPYING 
 27   
 28  # Changelog 
 29  # --------- 
 30  # 
 31  # $Log: debug.py,v $ 
 32  # Revision 1.6  2006/05/13 17:23:42  diedrich 
 33  # Massive docstring update. 
 34  # 
 35  # Revision 1.5  2006/04/28 09:49:27  diedrich 
 36  # Docstring updates for epydoc 
 37  # 
 38  # Revision 1.4  2006/04/15 23:19:32  diedrich 
 39  # Added reset() method to sql log class. 
 40  # 
 41  # Revision 1.3  2005/12/31 18:28:05  diedrich 
 42  # - Updated year in copyright header ;) 
 43  # 
 44  # Revision 1.2  2005/12/18 22:35:46  diedrich 
 45  # - Inheritance 
 46  # - pgsql adapter 
 47  # - first unit tests 
 48  # - some more comments 
 49  # 
 50  # Revision 1.1.1.1  2005/11/20 14:55:46  diedrich 
 51  # Initial import 
 52  # 
 53  # 
 54  # 
 55   
 56  __docformat__ = "epytext en" 
 57   
 58  """ 
 59  orm's debug module was re-written in one of my brigher moments: 
 60   
 61  First of all it contains a class called _logstream which implements a 
 62  subset of Python's file interface. This class is instantiated three 
 63  times and the objects are provided as global variables: log, debug and 
 64  sql. Each of these have a verbose attribute which determines, it log, 
 65  debug or sql information are written to stderr. 
 66   
 67  Furthermore, the _logstream class contains a mechanism to 
 68  automatically add options to a Python optparse.option_parser 
 69  automatically. Example: 
 70   
 71      >>> parser = optparse.OptionParser(doc, version=__version__) 
 72      >>> log.add_option(parser) 
 73      >>> debug.add_option(parser) 
 74   
 75  resulting in these options: 
 76   
 77    -v, --verbose         Be verbose (to stderr) 
 78    -d, --debug           Print debug messages (to stderr) 
 79   
 80  sql only adds a long --show-sql option if used in this manner. If 
 81  you'd like to use other switches you'll have to copy the lines below 
 82  over to your program. 
 83   
 84  """ 
 85   
 86  import sys 
 87  from string import * 
 88   
 89   
 90 -class _logstream: 
 91      """     
 92      Implement a subset of the file interface to be used for status 
 93      messages.  Depending on its verbose flag, the write() method will 
 94      pass its argument to sys.stderr.write() or discard it. 
 95      """ 
 96 -    def __init__(self): 
 97          self.verbose = False 
 98           
 99 -    def write(self, s): 
100          if self.verbose: 
101              sys.stderr.write(s) 
102   
103 -    def flush(self): 
104          if self.verbose: 
105              sys.stderr.flush() 
106   
107 -    def __call__(self, option, opt, value, parser): 
108          """ 
109          Called by the Option Parser when the command line option 
110          added by the add_option method() implemented by the two child 
111          classes is present. 
112          """ 
113          self.verbose = True 
114   
115 -    def __nonzero__(self): 
116          """ 
117          Return true if logging is ON, otherwise return False. This is ment 
118          to be used in if clauses:: 
119   
120             if debug: 
121                print 'Debug!' 
122          """ 
123          if self.verbose: 
124              return True 
125          else: 
126              return False 
127           
128           
129 -class _log(_logstream): 
130 -    def add_option(self, option_parser): 
131          option_parser.add_option("-v", "--verbose", action="callback", 
132                                   callback=self, help="Be verbose (to stderr)") 
133 -class _debug(_logstream): 
134 -    def add_option(self, option_parser): 
135          option_parser.add_option("-d", "--debug", action="callback", 
136                                   callback=self, 
137                                   help="Print debug messages (to stderr)") 
138           
139 -class _sql(_logstream): 
140      """ 
141      The _sql class has a logging mechanism that is controlled through 
142      the buffer_size attribute. If buffer_size is greater than 0, buffer_size 
143      sql statements will be retained in a list attribute called queries. This 
144      is used by unit tests to see if queries are generated as expected. 
145      """ 
146       
147 -    def __init__(self): 
148          _logstream.__init__(self) 
149          self.buffer_size = 0 
150          self.queries = [] 
151           
152 -    def write(self, s): 
153          _logstream.write(self, s) 
154   
155          s = strip(s) 
156          if s == "": return 
157   
158          if self.buffer_size > 0: 
159              self.queries.append(s) 
160              if len(self.queries) > self.buffer_size: 
161                  del self.queries[0] 
162   
163 -    def reset(self): 
164          self.queries = [] 
165           
166 -    def add_option(self, option_parser): 
167          option_parser.add_option("--show-sql", action="callback", 
168                                   callback=self, 
169                                   help="Log SQL queries and commands (to stderr)") 
170           
171  log = _log() 
172  debug = _debug() 
173  sqllog = _sql() 
174