maestral.sync

This module contains the main syncing functionality.

class maestral.sync.Conflict(value)[source]

Bases: enum.Enum

Enumeration of sync conflict types

RemoteNewer = 'remote newer'

Conflict = 'conflict'

Identical = 'identical'

LocalNewerOrIdentical = 'local newer or identical'

class maestral.sync.SyncDirection(value)[source]

Bases: enum.Enum

Enumeration of sync directions

Up = 'up'

Down = 'down'

class maestral.sync.FSEventHandler(file_event_types=('created', 'deleted', 'modified', 'moved'), dir_event_types=('created', 'deleted', 'moved'))[source]

Bases: watchdog.events.FileSystemEventHandler

A local file event handler

Handles captured file events and adds them to SyncEngine’s file event queue to be uploaded by upload_worker(). This acts as a translation layer between watchdog.Observer and SyncEngine.

White lists of event types to handle are supplied as file_event_types and dir_event_types. This is for forward compatibility as additional event types may be added to watchdog in the future.

Parameters

file_event_types (Tuple[str, ...]) – Types of file events to handle. This acts as a whitelist.
dir_event_types (Tuple[str, ...]) – Types of folder events to handle. This acts as a whitelist.

Variables

ignore_timeout (float) – Timeout in seconds after which filters for ignored events will expire.

Return type

None

local_file_event_queue: queue.Queue[watchdog.events.FileSystemEvent]

property enabled: bool: Whether queuing of events is enabled.

enable()[source]

Turn on queueing of events.

Return type: None

disable()[source]

Turn off queueing of new events and remove all events from queue.

Return type: None

ignore(*events, recursive=True)[source]

A context manager to ignore local file events

Once a matching event has been registered, further matching events will no longer be ignored unless recursive is True. If no matching event has occurred before leaving the context, the event will be ignored for ignore_timeout sec after leaving then context and then discarded. This accounts for possible delays in the emission of local file system events.

This context manager is used to filter out file system events caused by maestral itself, for instance during a download or when moving a conflict.

Example

Prevent triggereing a sync event when creating a local file:

>>> from watchdog.events import FileCreatedEvent
>>> from maestral.main import Maestral
>>> m = Maestral()
>>> with m.sync.fs_events.ignore(FileCreatedEvent('path')):
...     open('path').close()

Parameters

events (watchdog.events.FileSystemEvent) – Local events to ignore.
recursive (bool) – If True, all child events of a directory event will be ignored as well. This parameter will be ignored for file events.

Return type

Iterator[None]

expire_ignored_events()[source]

Removes all expired ignore entries.

Return type: None

on_any_event(event)[source]

Checks if the system file event should be ignored. If not, adds it to the queue for events to upload. If syncing is paused or stopped, all events will be ignored.

Parameters: event (watchdog.events.FileSystemEvent) – Watchdog file event.
Return type: None

queue_event(event)[source]

Queues an individual file system event. Notifies / wakes up all threads that are waiting with wait_for_event().

Parameters: event (watchdog.events.FileSystemEvent) – File system event to queue.
Return type: None

wait_for_event(timeout=40)[source]

Blocks until an event is available in the queue or a timeout occurs, whichever comes first. You can use with method to wait for file system events in another thread.

Note

If there are multiple threads waiting for events, all of them will be notified. If one of those threads starts getting events from local_file_event_queue, other threads may find that the queue is empty despite being woken. You should therefore be prepared to handle an empty queue even if this method returns True.

Parameters: timeout (float) – Maximum time to block in seconds.
Returns: True if an event is available, False if the call returns due to a timeout.
Return type: bool

class maestral.sync.SyncEngine(client)[source]

Bases: object

Class that handles syncing with Dropbox

Provides methods to wait for local or remote changes and sync them, including conflict resolution and updates to our index.

Parameters: client (maestral.client.DropboxClient) – Dropbox API client instance.

sync_errors: Set[maestral.errors.SyncError]

syncing: Dict[str, maestral.database.SyncEvent]

reload_cached_config()[source]

Reloads all config and state values that are otherwise cached by this class for faster access. Call this method if config or state values where modified directly instead of using SyncEngine APIs.

Return type: None

property dropbox_path: str: Path to local Dropbox folder, as loaded from the config file. Before changing dropbox_path, make sure that syncing is paused. Move the dropbox folder to the new location before resuming the sync. Changes are saved to the config file.

property is_fs_case_sensitive: bool: Whether the local Dropbox directory lies on a case-sensitive file system.

property database_path: str: Path SQLite database.

property file_cache_path: str: Path to cache folder for temporary files (read only). The cache folder ‘.maestral.cache’ is located inside the local Dropbox folder to prevent file transfer between different partitions or drives during sync.

property excluded_items: List[str]: List of all files and folders excluded from sync. Changes are saved to the config file. If a parent folder is excluded, its children will automatically be removed from the list. If only children are given but not the parent folder, any new items added to the parent will be synced. Change this property before downloading newly included items or deleting excluded items.

static clean_excluded_items_list(folder_list)[source]

Removes all duplicates and children of excluded items from the excluded items list. Normalises all paths to lower case.

Parameters: folder_list (List[str]) – Dropbox paths to exclude.
Returns: Cleaned up items.
Return type: List[str]

property max_cpu_percent: float: Maximum CPU usage for parallel downloads or uploads in percent of the total available CPU time per core. Individual workers in a thread pool will pause until the usage drops below this value. Tasks in the main thread such as indexing file changes may still use more CPU time. Setting this to 200% means that two full logical CPU core can be used.

property remote_cursor: str: Cursor from last sync with remote Dropbox. The value is updated and saved to the config file on every successful download of remote changes.

property local_cursor: float: Time stamp from last sync with remote Dropbox. The value is updated and saved to the config file on every successful upload of local changes.

property last_change: float: The time stamp of the last file change or 0.0 if there are no file changes in our history.

property last_reindex: float: Time stamp of last full indexing. This is used to determine when the next full indexing should take place.

property history: List[maestral.database.SyncEvent]: A list of the last SyncEvents in our history. History will be kept for the interval specified by the config value keep_history (defaults to two weeks) but at most 1,000 events will be kept.

clear_sync_history()[source]

Clears the sync history.

Return type: None

reset_sync_state()[source]

Resets all saved sync state. Settings are not affected.

Return type: None

get_index()[source]

Returns a copy of the local index of synced files and folders.

Returns: List of index entries.
Return type: List[maestral.database.IndexEntry]

iter_index()[source]

Returns an iterator over the local index of synced files and folders.

Returns: Iterator over index entries.
Return type: Iterator[maestral.database.IndexEntry]

index_count()[source]

Returns the number if items in our index without loading any items.

Returns: Number of index entries.
Return type: int

get_local_rev(dbx_path_lower)[source]

Gets revision number of local file.

Parameters: dbx_path_lower (str) – Normalized lower case Dropbox path.
Returns: Revision number as str or None if no local revision number has been saved.
Return type: Optional[str]

get_last_sync(dbx_path_lower)[source]

Returns the timestamp of last sync for an individual path.

Parameters: dbx_path_lower (str) – Normalized lower case Dropbox path.
Returns: Time of last sync.
Return type: float

get_index_entry(dbx_path_lower)[source]

Gets the index entry for the given Dropbox path.

Parameters: dbx_path_lower (str) – Normalized lower case Dropbox path.
Returns: Index entry or None if no entry exists for the given path.
Return type: Optional[maestral.database.IndexEntry]

get_local_hash(local_path)[source]

Computes content hash of a local file.

Parameters: local_path (str) – Absolute path on local drive.
Returns: Content hash to compare with Dropbox’s content hash, or ‘folder’ if the path points to a directory. None if there is nothing at the path.
Return type: Optional[str]

get_local_symlink_target(local_path)[source]

Gets the symlink target of a local file.

Parameters: local_path (str) – Absolute path on local drive.
Returns: Symlink target of local file. None if the local path does not refer to a symlink or does not exist.
Return type: Optional[str]

clear_hash_cache()[source]

Clears the sync history.

Return type: None

update_index_from_sync_event(event)[source]

Updates the local index from a SyncEvent.

Parameters: event (maestral.database.SyncEvent) – SyncEvent from download.
Return type: None

update_index_from_dbx_metadata(md, client=None)[source]

Updates the local index from Dropbox metadata.

Parameters

md (dropbox.files.Metadata) – Dropbox metadata.
client (Optional[maestral.client.DropboxClient]) – DropboxClient instance to use. If not given, use the global instance.

Return type

None

remove_node_from_index(dbx_path_lower)[source]

Removes any local index entries for the given path and all its children.

Parameters: dbx_path_lower (str) – Normalized lower case Dropbox path.
Return type: None

clear_index()[source]

Clears the revision index.

Return type: None

property mignore_path: str: Path to mignore file on local drive (read only).

property mignore_rules: pathspec.pathspec.PathSpec: List of mignore rules following git wildmatch syntax (read only).

load_mignore_file()[source]

Loads rules from mignore file. No rules are loaded if the file does not exist or cannot be read.

Returns: PathSpec instance with ignore patterns.
Return type: None

ensure_dropbox_folder_present()[source]

Checks if the Dropbox folder still exists where we expect it to be.

Raises: NoDropboxDirError – When local Dropbox directory does not exist.
Return type: None

ensure_cache_dir_present()[source]

Checks for or creates a directory at file_cache_path.

Raises: CacheDirError – When local cache directory cannot be created.
Return type: None

clean_cache_dir(raise_error=True)[source]

Removes all items in the cache directory.

Parameters: raise_error (bool) – Whether errors should be raised or only logged.
Return type: None

correct_case(dbx_path, client=None)[source]

Converts a Dropbox path with correctly cased basename to a fully cased path. This is useful because the Dropbox API guarantees the correct casing for the basename only. In practice, casing of parent directories is often incorrect. This method retrieves the correct casing of all ancestors in the path, either from our cache, our database, or from Dropbox servers.

Performance may vary significantly with the number of parent folders and the method used to resolve the casing of all parent directory names:

If the parent directory is already in our cache, performance is O(1).
If the parent directory is already in our sync index, performance is slower because it requires a sqlite query but still O(1).
If the parent directory is unknown to us, its metadata (including the correct casing of directory’s basename) is queried from Dropbox. This is used to construct a correctly cased path by calling correct_case() again. At best, performance will be of O(2) if the parent directory is known to us, at worst it will be of order O(n) involving queries to Dropbox servers for each parent directory.

When calling correct_case() repeatedly for paths from the same tree, it is therefore best to do so in hierarchical order.

Parameters

dbx_path (str) – Dropbox path with correctly cased basename, as provided by dropbox.files.Metadata.path_display or dropbox.files.Metadata.name.
client (Optional[maestral.client.DropboxClient]) – Client instance to use. If not given, use the instance provided in the constructor.

Returns

Correctly cased Dropbox path.

Return type

str

to_dbx_path(local_path)[source]

Converts a local path to a path relative to the Dropbox folder. Casing of the given local_path will be preserved.

Parameters: local_path (str) – Absolute path on local drive.
Returns: Relative path with respect to Dropbox folder.
Raises: ValueError – When the path lies outside the local Dropbox folder.
Return type: str

to_dbx_path_lower(local_path)[source]

Converts a local path to a path relative to the Dropbox folder. The path will be normalized as on Dropbox servers (lower case and some additional normalisations).

Parameters: local_path (str) – Absolute path on local drive.
Returns: Relative path with respect to Dropbox folder.
Raises: ValueError – When the path lies outside the local Dropbox folder.
Return type: str

to_local_path_from_cased(dbx_path_cased)[source]

Converts a correctly cased Dropbox path to the corresponding local path. This is more efficient than to_local_path() which accepts uncased paths.

Parameters: dbx_path_cased (str) – Path relative to Dropbox folder, correctly cased.
Returns: Corresponding local path on drive.
Return type: str

to_local_path(dbx_path, client=None)[source]

Converts a Dropbox path to the corresponding local path. Only the basename must be correctly cased, as guaranteed by the Dropbox API for the display_path attribute of file or folder metadata.

This method slower than to_local_path_from_cased().

Parameters

dbx_path (str) – Path relative to Dropbox folder, must be correctly cased in its basename.
client (Optional[maestral.client.DropboxClient]) – Client instance to use. If not given, use the instance provided in the constructor.

Returns

Corresponding local path on drive.

Return type

str

has_sync_errors()[source]

Returns True in case of sync errors, False otherwise.

Return type: bool

clear_sync_error(event)[source]

Clears all sync errors after a successful sync event.

Parameters: event (maestral.database.SyncEvent) – Successfully applied sync event.
Return type: None

clear_sync_errors()[source]

Clears all sync errors.

Return type: None

is_excluded(path)[source]

Checks if a file is excluded from sync. Certain file names are always excluded from syncing, following the Dropbox support article:

https://help.dropbox.com/installs-integrations/sync-uploads/files-not-syncing

This includes file system files such as ‘desktop.ini’ and ‘.DS_Store’ and some temporary files as well as caches used by Dropbox or Maestral. is_excluded accepts both local and Dropbox paths.

Parameters: path (str) – Can be an absolute path, a path relative to the Dropbox folder or just a file name. Does not need to be normalized.
Returns: Whether the path is excluded from syncing.
Return type: bool

is_excluded_by_user(dbx_path_lower)[source]

Check if file has been excluded through “selective sync” by the user.

Parameters: dbx_path_lower (str) – Normalised lower case Dropbox path.
Returns: Whether the path is excluded from download syncing by the user.
Return type: bool

is_mignore(event)[source]

Check if local file change has been excluded by a mignore pattern.

Parameters: event (maestral.database.SyncEvent) – SyncEvent for local file event.
Returns: Whether the path is excluded from upload syncing by the user.
Return type: bool

cancel_sync()[source]

Raises a maestral.errors.CancelledError in all sync threads and waits for them to shut down.

Return type: None

busy()[source]

Checks if we are currently syncing.

Returns: True if sync_lock cannot be acquired, False otherwise.
Return type: bool

upload_local_changes_while_inactive()[source]

Collects changes while sync has not been running and uploads them to Dropbox. Call this method when resuming sync.

Return type: None

wait_for_local_changes(timeout=40)[source]

Blocks until local changes are available.

Parameters: timeout (float) – Maximum time in seconds to wait.
Returns: True if changes are available, False otherwise.
Return type: bool

upload_sync_cycle()[source]

Performs a full upload sync cycle by calling in order:

list_local_changes()

apply_local_changes()

Handles updating the local cursor for you. If monitoring for local file events was interrupted, call upload_local_changes_while_inactive() instead.

list_local_changes(delay=1)[source]

Waits for local file changes. Returns a list of local changes with at most one entry per path.

Parameters: delay (float) – Delay in sec to wait for subsequent changes before returning.
Returns: (list of sync times events, time_stamp)
Return type: Tuple[List[maestral.database.SyncEvent], float]

apply_local_changes(sync_events)[source]

Applies locally detected changes to the remote Dropbox. Changes which should be ignored (mignore or always ignored files) are skipped.

Parameters: sync_events (List[maestral.database.SyncEvent]) – List of local file system events.
Return type: List[maestral.database.SyncEvent]

get_remote_item(dbx_path, client=None)[source]

Downloads a remote file or folder and updates its local rev. If the remote item does not exist, any corresponding local items will be deleted. If dbx_path refers to a folder, the download will be handled by _get_remote_folder(). If it refers to a single file, the download will be performed by _create_local_entry().

This method can be used to fetch individual items outside the regular sync cycle, for instance when including a previously excluded file or folder.

Parameters

dbx_path (str) – Path relative to Dropbox folder.
client (Optional[maestral.client.DropboxClient]) – Client instance to use. If not given, use the instance provided in the constructor.

Returns

Whether download was successful.

Return type

bool

wait_for_remote_changes(last_cursor, timeout=40, client=None)[source]

Blocks until changes to the remote Dropbox are available.

Parameters

last_cursor (str) – Cursor form last sync.
timeout (int) – Timeout in seconds before returning even if there are no changes. Dropbox adds random jitter of up to 90 sec to this value.
client (Optional[maestral.client.DropboxClient]) – Client instance to use. If not given, use the instance provided in the constructor.

Returns

True if changes are available, False otherwise.

Return type

bool

download_sync_cycle(client=None)[source]

Performs a full download sync cycle by calling in order:

list_remote_changes_iterator()

apply_remote_changes()

Handles updating the remote cursor and resuming interrupted syncs for you. Calling this method will perform a full indexing if this is the first download.

Parameters: client (Optional[maestral.client.DropboxClient]) – Client instance to use. If not given, use the instance provided in the constructor.
Return type: None

list_remote_changes_iterator(last_cursor, client=None)[source]

Get remote changes since the last download sync, as specified by last_cursor. If the last_cursor is from paginating through a previous set of changes, continue where we left off. If last_cursor is an empty string, perform a full indexing of the Dropbox folder.

Parameters

last_cursor (str) – Cursor from last download sync.
client (Optional[maestral.client.DropboxClient]) – Client instance to use. If not given, use the instance provided in the constructor.

Returns

Iterator yielding tuples with remote changes and corresponding cursor.

Return type

Iterator[Tuple[List[maestral.database.SyncEvent], str]]

apply_remote_changes(sync_events)[source]

Applies remote changes to local folder. Call this on the result of list_remote_changes(). The saved cursor is updated after a set of changes has been successfully applied. Entries in the local index are created after successful completion.

Parameters: sync_events (List[maestral.database.SyncEvent]) – List of remote changes.
Returns: List of changes that were made to local files and bool indicating if all download syncs were successful.
Return type: List[maestral.database.SyncEvent]

notify_user(sync_events, client=None)[source]

Shows a desktop notification for the given file changes.

Parameters

sync_events (List[maestral.database.SyncEvent]) – List of SyncEvents from download sync.
client (Optional[maestral.client.DropboxClient]) – Client instance to use. If not given, use the instance provided in the constructor.

Return type

None

rescan(local_path)[source]

Forces a rescan of a local path: schedules created events for every folder, modified events for every file and deleted events for every deleted item (compared to our index).

Parameters: local_path (str) – Path to rescan.
Return type: None