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.QtCore import QObject, Signal, QFileSystemWatcher 
 38  except: 
 39      pass 
 40   
 41   
 42 -class FileWatcher(QObject): 
 43      ''' 
 44      A class to watch for file changes. 
 45      ''' 
 46      config_changed = Signal(str, list) 
 47      '''@ivar: a signal to inform the receiver about the changes on 
 48      launch file or included file. 
 49      ParameterB{:} (changed file, list of tuples(masteruri, launch file))''' 
 50   
 51      binary_changed = Signal(str, list) 
 52      '''@ivar: a signal to inform the receiver about the changes on 
 53      binary file or included file. 
 54      ParameterB{:} (binary file, list of tuples(node name, masteruri, launchfile)) 
 55      ''' 
 56   
 57 -    def __init__(self): 
 58          QObject.__init__(self) 
 59          self.file_watcher = QFileSystemWatcher() 
 60          self.file_watcher.fileChanged.connect(self.on_file_changed) 
 61          self.changed = {} 
 62          self.launches = {} 
 63          self.binaries = {} 
 64   
 65 -    def __del__(self): 
 66          # Delete to avoid segfault if the LaunchConfig class is destroyed recently 
 67          # after creation and xmlrpclib.ServerProxy process a method call. 
 68          del self.file_watcher 
 69   
 70 -    def on_file_changed(self, filepath): 
 71          ''' 
 72          callback method, which is called by U{QtCore.QFileSystemWatcher<https://srinikom.github.io/pyside-docs/PySide/QtCore/QFileSystemWatcher.html>} 
 73          if one of a launch file, included files or binary are changed. 
 74          Depend on type of the file a L{FileWatcher.config_changed} or 
 75          L{FileWatcher.binary_changed} signal will be emitted. 
 76          ''' 
 77          # to avoid to handle from QFileSystemWatcher fired the signal two times 
 78          if (filepath not in self.changed or (filepath in self.changed and self.changed[filepath] + 0.05 < time.time())): 
 79              self.changed[filepath] = time.time() 
 80              launch_changes = [] 
 81              for (uri, lfile, _), files in self.launches.items():  # _:=id 
 82                  if filepath in files: 
 83                      launch_changes.append((uri, lfile)) 
 84              if launch_changes: 
 85                  self.config_changed.emit(filepath, launch_changes) 
 86              binaries_changed = [] 
 87              for node_name, (binary_file, masteruri, launchfile) in self.binaries.items(): 
 88                  if filepath == binary_file: 
 89                      binaries_changed.append((node_name, masteruri, launchfile)) 
 90              if binaries_changed: 
 91                  self.binary_changed.emit(filepath, binaries_changed) 
 92   
 93 -    def add_launch(self, masteruri, launch_file, launch_id, files): 
 94          if (masteruri, launch_file, launch_id) in self.launches: 
 95              self.launches[(masteruri, launch_file, launch_id)].extend([os.path.normpath(f) for f in files]) 
 96          else: 
 97              self.launches[(masteruri, launch_file, launch_id)] = [os.path.normpath(f) for f in files] 
 98          self.update_files() 
 99   
100 -    def rem_launch(self, masteruri, launch_file='', launch_id=''): 
101          try: 
102              if launch_file: 
103                  if launch_id: 
104                      del self.launches[(masteruri, launch_file, launch_id)] 
105                  else: 
106                      for (uri, cfgfile, cfgid), _ in self.launches.items(): 
107                          if uri == masteruri and cfgfile == launch_file: 
108                              del self.launches[(uri, cfgfile, cfgid)] 
109              else: 
110                  for (uri, cfgfile, cfgid), _ in self.launches.items(): 
111                      if uri == masteruri: 
112                          del self.launches[(uri, cfgfile, cfgid)] 
113          except: 
114              pass 
115          self.update_files() 
116   
117 -    def add_binary(self, binary_file, node_name, masteruri, launchfile): 
118          self.binaries[node_name] = (binary_file, masteruri, launchfile) 
119          self.update_files() 
120   
121 -    def rem_binary(self, node_name): 
122          try: 
123              del self.binaries[node_name] 
124              self.update_files() 
125          except: 
126              pass 
127   
128 -    def update_files(self): 
129          result = set() 
130          for files in self.launches.itervalues(): 
131              result.update(set(files)) 
132          binaries = set() 
133          for _, (binary_file, _, _) in self.binaries.items(): 
134              binaries.add(binary_file) 
135          result.update(binaries) 
136          files = set(self.file_watcher.files()) 
137          to_remove = list(files - result) 
138          if to_remove: 
139              self.file_watcher.removePaths(to_remove) 
140          to_add = list(result - files) 
141          if to_add: 
142              self.file_watcher.addPaths(to_add) 
143