X-Git-Url: https://git.mdrn.pl/wolnelektury.git/blobdiff_plain/80d3980873a2c07121f466c187de92be1cea8415..1cf1830b0f97f0c517862c8a2030e2fc4d76108e:/apps/catalogue/utils.py?ds=sidebyside diff --git a/apps/catalogue/utils.py b/apps/catalogue/utils.py index 7a405ba80..0134701a6 100644 --- a/apps/catalogue/utils.py +++ b/apps/catalogue/utils.py @@ -2,12 +2,22 @@ # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later. # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information. # +from __future__ import with_statement + import random import time from base64 import urlsafe_b64encode +from django.core.files.uploadedfile import UploadedFile from django.utils.hashcompat import sha_constructor from django.conf import settings +from celery.task import task +from os import mkdir, path, unlink +from errno import EEXIST, ENOENT +from fcntl import flock, LOCK_EX +from zipfile import ZipFile + +from librarian import DocProvider # Use the system (hardware-based) random number generator if it exists. @@ -30,3 +40,94 @@ def split_tags(tags): for tag in tags: result.setdefault(tag.category, []).append(tag) return result + + +class ExistingFile(UploadedFile): + + def __init__(self, path, *args, **kwargs): + self.path = path + return super(ExistingFile, self).__init__(*args, **kwargs) + + def temporary_file_path(self): + return self.path + + def close(self): + pass + + +class ORMDocProvider(DocProvider): + """Used for getting books' children.""" + + def __init__(self, book): + self.book = book + + def by_slug(self, slug): + if slug == self.book.slug: + return self.book.xml_file + else: + return type(self.book).objects.get(slug=slug).xml_file + + +class LockFile(object): + """ + A file lock monitor class; createas an ${objname}.lock + file in directory dir, and locks it exclusively. + To be used in 'with' construct. + """ + def __init__(self, dir, objname): + self.lockname = path.join(dir, objname + ".lock") + + def __enter__(self): + self.lock = open(self.lockname, 'w') + flock(self.lock, LOCK_EX) + + def __exit__(self, *err): + try: + unlink(self.lockname) + except OSError as oe: + if oe.errno != oe.EEXIST: + raise oe + self.lock.close() + + +@task +def create_zip(paths, zip_slug): + """ + Creates a zip in MEDIA_ROOT/zip directory containing files from path. + Resulting archive filename is ${zip_slug}.zip + Returns it's path relative to MEDIA_ROOT (no initial slash) + """ + # directory to store zip files + zip_path = path.join(settings.MEDIA_ROOT, 'zip') + + try: + mkdir(zip_path) + except OSError as oe: + if oe.errno != EEXIST: + raise oe + zip_filename = zip_slug + ".zip" + + with LockFile(zip_path, zip_slug): + if not path.exists(path.join(zip_path, zip_filename)): + zipf = ZipFile(path.join(zip_path, zip_filename), 'w') + try: + for arcname, p in paths: + if arcname is None: + arcname = path.basename(p) + zipf.write(p, arcname) + finally: + zipf.close() + + return 'zip/' + zip_filename + + +def remove_zip(zip_slug): + """ + removes the ${zip_slug}.zip file from zip store. + """ + zip_file = path.join(settings.MEDIA_ROOT, 'zip', zip_slug + '.zip') + try: + unlink(zip_file) + except OSError as oe: + if oe.errno != ENOENT: + raise oe