Source Code for Module node_manager_fkie.file_watcher'

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 32   
 33  import os 
 34  import time 
 35   
 36  try: 
 37    from python_qt_binding import QtCore 
 38  except: 
 39    pass 
 40   
 41 -class FileWatcher(QtCore.QObject): 
 42    ''' 
 43    A class to watch for file changes. 
 44    ''' 
 45    file_changed = QtCore.Signal(str, list) 
 46    '''@ivar: a signal to inform the receiver about the changes on 
 47    launch file or included file. ParameterB{:} (changed file, list of tuples(masteruri, launch file))''' 
 48     
 49 -  def __init__(self): 
 50      QtCore.QObject.__init__(self) 
 51      self.file_watcher = QtCore.QFileSystemWatcher() 
 52      self.file_watcher.fileChanged.connect(self.on_file_changed) 
 53      self.changed = {} 
 54      self.launches = {} 
 55   
 56 -  def __del__(self): 
 57      # Delete to avoid segfault if the LaunchConfig class is destroyed recently  
 58      # after creation and xmlrpclib.ServerProxy process a method call. 
 59      del self.file_watcher 
 60   
 61 -  def on_file_changed(self, file): 
 62      ''' 
 63      callback method, which is called by L{QtCore.QFileSystemWatcher} if the  
 64      launch file or included files are changed. In this case  
 65      L{FileWatcher.file_changed} signal will be emitted. 
 66      ''' 
 67      # to avoid to handle from QFileSystemWatcher fired the signal two times 
 68      if (not self.changed.has_key(file) or (self.changed.has_key(file) and self.changed[file] + 0.05 < time.time())): 
 69        self.changed[file] = time.time() 
 70        changes = [] 
 71        for (uri, lfile, _), files in self.launches.items():#_:=id 
 72          if file in files: 
 73            changes.append((uri, lfile)) 
 74        self.file_changed.emit(file, changes) 
 75   
 76 -  def add(self, masteruri, launch_file, launch_id, files): 
 77      if self.launches.has_key((masteruri, launch_file, launch_id)): 
 78        self.launches[(masteruri, launch_file, launch_id)].extend([os.path.normpath(f) for f in files]) 
 79      else: 
 80        self.launches[(masteruri, launch_file, launch_id)] = [os.path.normpath(f) for f in files] 
 81      self.update_files() 
 82   
 83 -  def rem(self, masteruri, launch_file='', launch_id=''): 
 84      try: 
 85        if launch_file: 
 86          if launch_id: 
 87            del self.launches[(masteruri, launch_file, launch_id)] 
 88          else: 
 89            for (uri, file, id), files in self.launches.items(): 
 90              if uri == masteruri and file == launch_file: 
 91                del self.launches[(uri, file, id)] 
 92        else: 
 93          for (uri, file, id), files in self.launches.items(): 
 94            if uri == masteruri: 
 95              del self.launches[(uri, file, id)] 
 96      except: 
 97  #      import traceback 
 98  #      print traceback.format_exc(1) 
 99        pass 
100      self.update_files() 
101   
102 -  def update_files(self): 
103      result = set() 
104      for files in self.launches.itervalues(): 
105        result.update(set(files)) 
106      files = self.file_watcher.files() 
107      if files: 
108        self.file_watcher.removePaths(files) 
109      if list(result): 
110        self.file_watcher.addPaths(list(result)) 
111