.. _label-filechangehandler:

##################
FileChangeHandler
##################

.. py:class:: FileChangeHandler(directory, extensions, options)

   This handler is responsible for handling changed file events in antiweb's daemon mode.

   :param string directory: absolute path to the monitored source directory
   :param tuple<string> extensions: contains all handled file extensions ("*.cs", "*.py", etc)
   :param options: antiweb commandline options
   :param created_files: a set which contains the absolute paths of all previously created documentation files


::

    class FileChangeHandler(FileSystemEventHandler):
    
        def __init__(self, directory, extensions, options, created_files):
            self._directory = directory
            #antiweb commandline options
            self._options = options
            self._handled_extensions = extensions
            self._event_counter = 0
            self._created_files = set()
            self._created_files.update(created_files)
    



.. py:method:: process_event(self, event)

   Handles the file events: 'modified' | 'created' | 'moved' | 'deleted'.

   The events trigger an update of the corresponding documentation file.
   Ignored events are: deleted files, changed directories, files without a handled extension and changes of
   antiweb's created documentation files.

   :param event: The file event that should be handled. Possible event types: 'modified' | 'created' | 'moved' | 'deleted'


::

    
        def process_event(self, event):
    
            self._event_counter += 1
            time_stamp = "[" + time.strftime('%H:%M:%S') + " " + str(self._event_counter).zfill(5) + "] "
    
            changed_file = event.src_path
    
            if event.event_type == "moved":
                #moved event has to be handled differently:
                #the file has been moved so it is now located in event.dest_path
                changed_file = event.dest_path
    
            ignore_change = changed_file in self._created_files or not changed_file.endswith(self._handled_extensions) or \
                      event.is_directory or event.event_type == "deleted"
    
            if not ignore_change:
                #process change
                created_file = write(self._directory, changed_file, self._options, False)
    
                if created_file:
                    self._created_files.add(created_file)
    
                event_string = create_write_string(changed_file, created_file)
            else:
                #ignore change
                event_string = "Ignored change: " + changed_file + " [" + event.event_type + "]"
    
            #using autoflush to immediately print the output
            print(time_stamp + event_string, flush=True)
    


-   events 'created', 'modified', 'moved' and 'deleted' are handled by the process_event method
-   event 'moved' is triggered when a subdirectory of the monitored source directory
    contains monitored files and the subdirectory is renamed
-   note that when a file is modified/created watchdog may get multiple events


::

    
    def on_modified(self, event):
        self.process_event(event)
    
    def on_created(self, event):
        self.process_event(event)
    
    def on_moved(self, event):
        #this event is triggered when a src directory contains a subdirectory with some files
        #and the subdirectory is renamed. the event is then triggered for all files within
        #the subdirectory and the subdirectory itself
        self.process_event(event)
    
    def on_deleted(self, event):
        self.process_event(event)