# eric7.EricCore.EricFileSystemWatcher

Module implementing a QFileSystemWatcher replacement based on the 'watchdog' package.

### Global Attributes

_GlobalFileSystemWatcher

### Classes

EricFileSystemWatcher | Class implementing a file system monitor based on the 'watchdog' package as a replacement for 'QFileSystemWatcher'.
_EricFileSystemEventHandler | Class implementing a QObject based file system event handler for watchdog.

### Functions

instance | Function to get a reference to the global file system monitor object.

## EricFileSystemWatcher

Class implementing a file system monitor based on the 'watchdog' package as a replacement for 'QFileSystemWatcher'.

This class has more fine grained signaling capability compared to QFileSystemWatcher. The 'directoryChanged' and 'fileChanged' signals are emitted to keep the API compatible with QFileSystemWatcher.

Note: On Linux and macOS systems it might be necessary to increase the limit of open file descriptors to at least 1024. This can be done by including the command 'ulimit -n 1024' in the users profile file (~/.profile).

### Signals

directoryChanged(path: str)
  emitted when the directory at a given path is modified or removed from disk
directoryCreated(path: str)
  emitted when a directory is created
directoryDeleted(path: str)
  emitted when a directory is removed from disk
directoryModified(path: str)
  emitted when a directory is modified
directoryMoved(srcPath: str, dstPath: str)
  emitted when the directory at a given source path is renamed or moved to destination path
error(errno: int, errmsg: str)
  emitted to indicate an OS error
fileChanged(path: str)
  emitted when the file at a given path is modified or removed from disk
fileClosed(path: str)
  emitted when a file opened for writing is closed
fileClosedNoWrite(path: str)
  emitted when a file opened for reading is closed
fileCreated(path: str)
  emitted when a file is created
fileDeleted(path: str)
  emitted when a file is removed from disk
fileModified(path: str)
  emitted when a file is modified
fileMoved(srcPath: str, dstPath: str)
  emitted when the file at a given source path is renamed or moved to destination path

### Derived from

QObject

### Class Attributes

None

### Class Methods

None

### Methods

EricFileSystemWatcher | Constructor
__del__ | Special method called when an instance object is about to be destroyed.
__directoryChanged | Private slot handling any change of a directory at a given path.
__fileChanged | Private slot handling any change of a file at a given path.
addPath | Public method to add the given path to the list of watched paths.
addPaths | Public method to add each path of the given list to the file system watched.
directories | Public method to return a list of paths to directories that are being watched.
files | Public method to return a list of paths to files that are being watched.
paths | Public method to return a list of paths that are being watched.
removePath | Public method to remove a given path from the list of monitored paths.
removePaths | Public method to remove the specified paths from the list of monitored paths.
shutdown | Public method to shut down the file system watcher instance.

### Static Methods

None

#### EricFileSystemWatcher (Constructor)

EricFileSystemWatcher(parent=None)

Constructor

parent (QObject (optional))
  reference to the parent object (defaults to None)

#### EricFileSystemWatcher.__del__

__del__()

Special method called when an instance object is about to be destroyed.

#### EricFileSystemWatcher.__directoryChanged

__directoryChanged(path)

Private slot handling any change of a directory at a given path.

It emits the signal 'directoryChanged', if the path is in the list of watched paths. This behavior is compatible with the QFileSystemWatcher signal of identical name.

path (str)
  path name of the changed directory

#### EricFileSystemWatcher.__fileChanged

__fileChanged(path)

Private slot handling any change of a file at a given path.

It emits the signal 'fileChanged', if the path is in the list of watched paths. This behavior is compatible with the QFileSystemWatcher signal of identical name.

path (str)
  path name of the changed file

#### EricFileSystemWatcher.addPath

addPath(path, recursive=False)

Public method to add the given path to the list of watched paths.

If the given path is a directory, a recursive watch may be requested. Otherwise only the given directory is watched for changes but none of its subdirectories.

The path is not added, if it does not exist or if it is already being monitored by the file system watcher.

path (str)
  file or directory path to be added to the watched paths
recursive (bool (optional))
  flag indicating a watch for the complete tree rooted at the given path (for directory paths only) (defaults to False)

Return:
  flag indicating a successful creation of a watch for the given path

Return Type:
  bool

#### EricFileSystemWatcher.addPaths

addPaths(paths, recursive=False)

Public method to add each path of the given list to the file system watched.

If a path of the given paths list is a directory, a recursive watch may be requested. Otherwise only the given directory is watched for changes but none of its subdirectories. This applies to all directory paths of the given list.

A path of the list is not added, if it does not exist or if it is already being monitored by the file system watcher.

paths (list of str)
  list of file or directory paths to be added to the watched paths
recursive (bool (optional))
  flag indicating a watch for the complete tree rooted at the given path (for directory paths only) (defaults to False)

Return:
  list of paths that could not be added to the list of monitored paths

Return Type:
  list of str

#### EricFileSystemWatcher.directories

directories()

Public method to return a list of paths to directories that are being watched.

Return:
  list of watched directory paths

Return Type:
  list of str

#### EricFileSystemWatcher.files

files()

Public method to return a list of paths to files that are being watched.

Return:
  list of watched file paths

Return Type:
  list of str

#### EricFileSystemWatcher.paths

paths()

Public method to return a list of paths that are being watched.

Return:
  list of all watched paths

Return Type:
  list of str

#### EricFileSystemWatcher.removePath

removePath(path)

Public method to remove a given path from the list of monitored paths.

path (str)
  directory or file path to be removed

Return:
  flag indicating a successful removal. The only reason for a failure is, if the given path is not currently being monitored.

Return Type:
  bool

#### EricFileSystemWatcher.removePaths

removePaths(paths)

Public method to remove the specified paths from the list of monitored paths.

paths (list of str)
  list of directory or file paths to be removed

Return:
  list of paths that could not be removed from the list of monitored paths

Return Type:
  list of str

#### EricFileSystemWatcher.shutdown

shutdown()

Public method to shut down the file system watcher instance.

This needs to be done in order to stop the monitoring threads doing their work in the background. If this method was not called explicitly when the instance is about to be destroyed, the special method '__del__' will do that.

Up

## _EricFileSystemEventHandler

Class implementing a QObject based file system event handler for watchdog.

### Signals

directoryChanged(path: str)
  emitted when the directory at a given path is modified or removed from disk
directoryCreated(path: str)
  emitted when a directory is created
directoryDeleted(path: str)
  emitted when a directory is removed from disk
directoryModified(path: str)
  emitted when a directory is modified
directoryMoved(srcPath: str, dstPath: str)
  emitted when the directory at a given source path is renamed or moved to destination path
fileChanged(path: str)
  emitted when the file at a given path is modified or removed from disk
fileClosed(path: str)
  emitted when a file opened for writing is closed
fileClosedNoWrite(path: str)
  emitted when a file opened for reading is closed
fileCreated(path: str)
  emitted when a file is created
fileDeleted(path: str)
  emitted when a file is removed from disk
fileModified(path: str)
  emitted when a file is modified
fileMoved(srcPath: str, dstPath: str)
  emitted when the file at a given source path is renamed or moved to destination path

### Derived from

QObject, FileSystemEventHandler

### Class Attributes

None

### Class Methods

None

### Methods

_EricFileSystemEventHandler | Constructor
on_any_event | Private method handling any file system event.
on_closed | Private method to handle a closing event for a file that was opened for writing.
on_closed_no_write | Private method to handle a closing event for a file that was opened for reading.
on_created | Private method to handle a creation event.
on_deleted | Private method to handle a deletion event.
on_modified | Private method to handle a modification event.
on_moved | Private method to handle a move or rename event.

### Static Methods

None

#### _EricFileSystemEventHandler (Constructor)

_EricFileSystemEventHandler(parent=None)

Constructor

parent (QObject (optional))
  reference to the parent object (defaults to None)

#### _EricFileSystemEventHandler.on_any_event

on_any_event(event)

Private method handling any file system event.

event (watchdog.events.FileSystemEvent)
  event to be handled

#### _EricFileSystemEventHandler.on_closed

on_closed(event)

Private method to handle a closing event for a file that was opened for writing.

event (watchdog.events.FileClosedEvent)
  event to be handled

#### _EricFileSystemEventHandler.on_closed_no_write

on_closed_no_write(event)

Private method to handle a closing event for a file that was opened for reading.

event (watchdog.events.FileClosedNoWriteEvent)
  event to be handled

#### _EricFileSystemEventHandler.on_created

on_created(event)

Private method to handle a creation event.

event (watchdog.events.FileCreatedEvent or watchdog.event.DirCreatedEvent)
  event to be handled

#### _EricFileSystemEventHandler.on_deleted

on_deleted(event)

Private method to handle a deletion event.

event (watchdog.events.FileDeletedEvent or watchdog.event.DirDeletedEvent)
  event to be handled

#### _EricFileSystemEventHandler.on_modified

on_modified(event)

Private method to handle a modification event.

event (watchdog.events.FileModifiedEvent or watchdog.event.DirModifiedEvent)
  event to be handled

#### _EricFileSystemEventHandler.on_moved

on_moved(event)

Private method to handle a move or rename event.

event (watchdog.events.FileMovedEvent or watchdog.event.DirMovedEvent)
  event to be handled

Up

## instance

instance()

Function to get a reference to the global file system monitor object.

If the global file system monitor does not exist yet, it will be created automatically.

Return:
  reference to the global file system monitor object

Return Type:
  EricFileSystemWatcher

Up