diff options
| -rw-r--r-- | fietsboek/actions.py | 32 | ||||
| -rw-r--r-- | fietsboek/data.py | 125 | ||||
| -rw-r--r-- | fietsboek/views/edit.py | 4 | ||||
| -rw-r--r-- | fietsboek/views/upload.py | 8 |
4 files changed, 141 insertions, 28 deletions
diff --git a/fietsboek/actions.py b/fietsboek/actions.py index f1a32fc..bba4185 100644 --- a/fietsboek/actions.py +++ b/fietsboek/actions.py @@ -8,14 +8,14 @@ the test functions. import datetime import logging import re -from typing import List +from typing import List, Optional from pyramid.request import Request from sqlalchemy import select from sqlalchemy.orm.session import Session from fietsboek import models, util -from fietsboek.data import DataManager +from fietsboek.data import DataManager, TrackDataDir from fietsboek.models.track import TrackType, Visibility LOGGER = logging.getLogger(__name__) @@ -81,22 +81,22 @@ def add_track( # Save the GPX data LOGGER.debug("Creating a new data folder for %d", track.id) - manager = data_manager.initialize(track.id) - LOGGER.debug("Saving GPX to %s", manager.gpx_path()) - manager.compress_gpx(gpx_data) - manager.backup() - - manager.engrave_metadata( - title=track.title, - description=track.description, - author_name=track.owner.name, - time=track.date, - ) + with data_manager.initialize(track.id) as manager: + LOGGER.debug("Saving GPX to %s", manager.gpx_path()) + manager.compress_gpx(gpx_data) + manager.backup() + + manager.engrave_metadata( + title=track.title, + description=track.description, + author_name=track.owner.name, + time=track.date, + ) return track -def edit_images(request: Request, track: models.Track): +def edit_images(request: Request, track: models.Track, *, manager: Optional[TrackDataDir] = None): """Edit the images according to the given request. This deletes and adds images and image descriptions as needed, based on the @@ -104,9 +104,11 @@ def edit_images(request: Request, track: models.Track): :param request: The request. :param track: The track to edit. + :param manager: The track's data manager. If not given, it will + automatically be opened from the request. """ LOGGER.debug("Editing images for %d", track.id) - manager = request.data_manager.open(track.id) + manager = manager if manager else request.data_manager.open(track.id) # Delete requested images for image in request.params.getall("delete-image[]"): diff --git a/fietsboek/data.py b/fietsboek/data.py index 1a1b66b..cbe20e9 100644 --- a/fietsboek/data.py +++ b/fietsboek/data.py @@ -10,7 +10,7 @@ import shutil import string import uuid from pathlib import Path -from typing import BinaryIO, List, Optional +from typing import BinaryIO, List, Literal, Optional import brotli import gpxpy @@ -77,7 +77,7 @@ class DataManager: """ path = self._track_data_dir(track_id) path.mkdir(parents=True) - return TrackDataDir(track_id, path) + return TrackDataDir(track_id, path, journal=True, is_fresh=True) def purge(self, track_id: int): """Forcefully purges all data from the given track. @@ -101,11 +101,94 @@ class DataManager: class TrackDataDir: - """Manager for a single track's data.""" + """Manager for a single track's data. + + If initialized with ``journal = True``, then you can use :meth:`rollback` + to roll back the changes in case of an error. In case of no error, use + :meth:`commit` to commit the changes. If you don't want the "journalling" + semantics, use ``journal = False``. + """ - def __init__(self, track_id: int, path: Path): + def __init__(self, track_id: int, path: Path, *, journal: bool = False, is_fresh: bool = False): self.track_id: int = track_id self.path: Path = path + self.journal: Optional[list] = [] if journal else None + self.is_fresh = is_fresh + + def __enter__(self) -> "TrackDataDir": + if self.journal is None: + self.journal = [] + return self + + def __exit__(self, exc_type, exc_val, exc_tb) -> Literal[False]: + if exc_type is None and exc_val is None and exc_tb is None: + self.commit() + else: + self.rollback() + return False + + def rollback(self): + """Rolls back the journal, e.g. in case of error. + + :raises ValueError: If the data directory was opened without the + journal, this raises :exc:`ValueError`. + """ + LOGGER.debug("Rolling back state of %s", self.path) + + if self.journal is None: + raise ValueError("Rollback on a non-journalling data directory") + + if self.is_fresh: + # Shortcut if the directory is fresh, simply remove everything + self.journal = None + self.purge() + return + + for action, *rest in reversed(self.journal): + if action == "purge": + (new_name,) = rest + shutil.move(new_name, self.path) + elif action == "compress_gpx": + (old_data,) = rest + if old_data is None: + self.gpx_path().unlink() + else: + self.gpx_path().write_bytes(old_data) + elif action == "add_image": + (image_path,) = rest + image_path.unlink() + elif action == "delete_image": + path, data = rest + path.write_bytes(data) + + self.journal = None + + def commit(self): + """Commits all changed and deletes the journal. + + Note that this function will do nothing if the journal is disabled, + meaning it can always be called. + """ + LOGGER.debug("Committing journal for %s", self.path) + + if self.journal is None: + return + + for action, *rest in reversed(self.journal): + if action == "purge": + (new_name,) = rest + shutil.rmtree(new_name, ignore_errors=False, onerror=self._log_deletion_error) + elif action == "compress_gpx": + # Nothing to do here, the new data is already on the disk + pass + elif action == "add_image": + # Nothing to do here, the image is already saved + pass + elif action == "delete_image": + # Again, nothing to do here, we simply discard the in-memory image data + pass + + self.journal = None def lock(self) -> FileLock: """Returns a FileLock that can be used to lock access to the track's @@ -115,18 +198,23 @@ class TrackDataDir: """ return FileLock(self.path / "lock") + @staticmethod + def _log_deletion_error(_, path, exc_info): + LOGGER.warning("Failed to remove %s", path, exc_info=exc_info) + def purge(self): """Purge all data pertaining to the track. This function logs errors but raises no exception, as such it can always be used to clean up after a track. """ - - def log_error(_, path, exc_info): - LOGGER.warning("Failed to remove %s", path, exc_info=exc_info) - - if self.path.is_dir(): - shutil.rmtree(self.path, ignore_errors=False, onerror=log_error) + if self.journal is None: + if self.path.is_dir(): + shutil.rmtree(self.path, ignore_errors=False, onerror=self._log_deletion_error) + else: + new_name = self.path.with_name("trash-" + self.path.name) + shutil.move(self.path, new_name) + self.journal.append(("purge", new_name)) def gpx_path(self) -> Path: """Returns the path of the GPX file. @@ -147,6 +235,16 @@ class TrackDataDir: :param quality: Compression quality, from 0 to 11 - 11 is highest quality but slowest compression speed. """ + if self.journal is not None: + # First, we check if we already saved an old state of the GPX data + for action, *_ in self.journal: + if action == "compress_gpx": + break + else: + # We did not save a state yet + old_data = None if not self.gpx_path().is_file() else self.gpx_path().read_bytes() + self.journal.append(("compress_gpx", old_data)) + compressed = brotli.compress(data, quality=quality) self.gpx_path().write_bytes(compressed) @@ -233,6 +331,9 @@ class TrackDataDir: with open(path, "wb") as fobj: shutil.copyfileobj(image, fobj) + if self.journal is not None: + self.journal.append(("add_image", path)) + return filename def delete_image(self, image_id: str): @@ -246,4 +347,8 @@ class TrackDataDir: if "/" in image_id or "\\" in image_id: return path = self.image_path(image_id) + + if self.journal is not None: + self.journal.append(("delete_image", path, path.read_bytes())) + path.unlink() diff --git a/fietsboek/views/edit.py b/fietsboek/views/edit.py index e3fe99d..61741e5 100644 --- a/fietsboek/views/edit.py +++ b/fietsboek/views/edit.py @@ -82,7 +82,7 @@ def do_edit(request): data: TrackDataDir = request.data_manager.open(track.id) tz_offset = datetime.timedelta(minutes=int(request.params["date-tz"])) date = datetime.datetime.fromisoformat(request.params["date"]) - with data.lock(): + with data, data.lock(): track.date = date.replace(tzinfo=datetime.timezone(tz_offset)) track.tagged_people = tagged_people @@ -94,7 +94,7 @@ def do_edit(request): tags = request.params.getall("tag[]") track.sync_tags(tags) - actions.edit_images(request, request.context) + actions.edit_images(request, request.context, manager=data) data.engrave_metadata( title=track.title, description=track.description, diff --git a/fietsboek/views/upload.py b/fietsboek/views/upload.py index e172339..ed8f285 100644 --- a/fietsboek/views/upload.py +++ b/fietsboek/views/upload.py @@ -176,7 +176,13 @@ def do_finish_upload(request): # Don't forget to add the images LOGGER.debug("Starting to edit images for the upload") - actions.edit_images(request, track) + try: + actions.edit_images(request, track) + except Exception: + # We just created the folder, so we'll be fine deleting it + LOGGER.info("Deleting partially created folder for track %d", track.id) + request.data_manager.open(track.id).purge() + raise request.session.flash(request.localizer.translate(_("flash.upload_success"))) |