Source Code for Module mathbench.basement.history_manager

  1  #!/usr/bin/python 
  2  # -*- coding: utf-8 -*- 
  3   
  4  """ 
  5  Handling of command history and their saving/loading in/from files. 
  6   
  7  The history is a list of commands (one item by command) to be 
  8  compatible with the history represenation in wx.Py.shell. 
  9  """ 
 10   
 11  import os 
 12  import time 
 13   
 14 -class HistoryManager(object): 
 15          """ 
 16          Manage the history of commands. 
 17          """ 
 18           
 19          # a separator that is a bit more that a line separator to be able 
 20          # to locate when the line ends because the commands ends or 
 21          # because we are writting a multiple line commands (eg class 
 22          # definition) (idea taken from wx.py itself...) 
 23          COMMANDS_SEPARATOR = '\x00\n' 
 24   
 25           
 26 -        def __init__(self, shell, history_dir, extension="session", max_file_nb=10): 
 27                  """ 
 28                  Initialise the manager. 
 29                   
 30                  ``history_dir`` 
 31                     
 32                      the directory where history files are supposed to be saved. 
 33                  """ 
 34                  self.shell = shell 
 35                  self.history_dir = history_dir 
 36                  self.extension = extension 
 37                  self.max_file_nb = max_file_nb 
 38                  self.put_landmark() 
 39   
 40 -        def get_history_files_info(self): 
 41                  """ 
 42                  Return the list of dates corresponding to the available history files. 
 43                  """ 
 44                  histo_list = [] 
 45                  for root, dirs, files in os.walk(self.history_dir):              
 46                          for filename in files: 
 47                                  if filename.endswith(".%s"%self.extension): 
 48                                          # then it should be a command history and the rest 
 49                                          # of the file should be in the following format: 
 50                                          # YYYYMMDD-hhmmss 
 51                                          histo_list.append(filename.rstrip(".%s"%self.extension)) 
 52                          # don't go into the hierachy of folders 
 53                          return histo_list 
 54   
 55 -        def load_session_at_date(self, dateinfo): 
 56                  """ 
 57                  Iterate over the list of command corresponding to the session at a 
 58                  given date, described by a string in the following format: 
 59   
 60                  YYYYMMDD-hhmmss 
 61                  """ 
 62                  f = open(os.path.join(self.history_dir,"%s.%s"%(dateinfo,self.extension))) 
 63                  hist = f.read() 
 64                  commands = hist.split(self.COMMANDS_SEPARATOR) 
 65                  # load all the commands in the shell's history 
 66                  for c in commands: 
 67                          self.shell.history.append(c) 
 68           
 69 -        def load_latest_session(self): 
 70                  """ 
 71                  Load the latest session. 
 72                  """ 
 73                  session_dates = self.get_history_files_info() 
 74                  # sort all 
 75                  session_dates.sort() 
 76                  if len(session_dates)>0: 
 77                          # take the latest 
 78                          self.load_session_at_date(session_dates[-1]) 
 79   
 80 -        def check_not_too_many_file(self): 
 81                  """ 
 82                  Check that there is not too many session file, and if there is 
 83                  remove the oldest. 
 84                  """ 
 85                  session_files = self.get_history_files_info() 
 86                  session_files.sort() 
 87                  while len(session_files)>self.max_file_nb: 
 88                          f = session_files.pop(0) 
 89                          os.remove(os.path.join(self.history_dir,"%s.%s"%(f,self.extension))) 
 90   
 91 -        def save_current_session(self): 
 92                  """ 
 93                  Save the history of a given file into a shell. 
 94                   
 95                  Save the session only after the landmark. 
 96                  """ 
 97                  lt = time.localtime() 
 98                  # create an appropriate date stamp to put in the file name 
 99                  date_stamp = "%s%#02d%#02d-%#02d%#02d%#02d" % (lt.tm_year,lt.tm_mon,lt.tm_mday, 
100                                                                                                             lt.tm_hour,lt.tm_min,lt.tm_sec) 
101                  # open the file and write all the commands 
102                  filename = os.path.join(self.history_dir,"%s.%s"%(date_stamp,self.extension)) 
103                  f = open(filename,"w") 
104                  f.write(self.COMMANDS_SEPARATOR.join(self.get_history_from_landmark())) 
105                  f.close() 
106                  # check that we have not exceeded the limit of such files 
107                  self.check_not_too_many_file() 
108                   
109 -        def put_landmark(self): 
110                  """ 
111                  Record the current length of the shell's history. 
112                  """ 
113                  self.landmark=len(self.shell.history) 
114   
115 -        def get_landmark(self): 
116                  """ 
117                  Record the length of the shell's history when the latest landmark was put. 
118                  """ 
119                  return self.landmark 
120   
121 -        def get_history_from_landmark(self): 
122                  """ 
123                  Return the list of commands entered since the latest landmark. 
124                  """ 
125  #               print self.landmark 
126  #               print self.shell.history 
127                  if self.landmark==0: 
128                          return self.shell.history[:] 
129                  else: 
130                          return self.shell.history[:-self.landmark] 
131