X-Git-Url: https://git.mdrn.pl/wolnelektury.git/blobdiff_plain/f37981065265afbb98a729e9ed8d6eec2e2763a0..462d84ea8718cd3ca1112fe11c2120a0f20f475f:/apps/catalogue/utils.py diff --git a/apps/catalogue/utils.py b/apps/catalogue/utils.py index d5ef2b789..0fdeaf810 100644 --- a/apps/catalogue/utils.py +++ b/apps/catalogue/utils.py @@ -8,17 +8,22 @@ import random import time from base64 import urlsafe_b64encode +from django.http import HttpResponse, HttpResponseRedirect, Http404, HttpResponsePermanentRedirect from django.core.files.uploadedfile import UploadedFile +from django.core.files.base import File +from django.core.files.storage import DefaultStorage 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 +from errno import EEXIST, ENOENT from fcntl import flock, LOCK_EX from zipfile import ZipFile +from traceback import print_exc -from librarian import DocProvider - +from reporting.utils import read_chunks +from celery.task import task +import catalogue.models # Use the system (hardware-based) random number generator if it exists. if hasattr(random, 'SystemRandom'): @@ -55,33 +60,35 @@ class ExistingFile(UploadedFile): pass -class BookImportDocProvider(DocProvider): - """Used for joined EPUB and PDF files.""" - - 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 __entry__(self): + 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() - unlink(self.lockname) +@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') @@ -94,22 +101,91 @@ def create_zip(paths, zip_slug): with LockFile(zip_path, zip_slug): if not path.exists(path.join(zip_path, zip_filename)): - with ZipFile(path.join(zip_path, zip_filename), 'w') as zipf: - for p in paths: - zipf.write(p, path.basename(p)) + 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 != EEXIST: + if oe.errno != ENOENT: raise oe +class AttachmentHttpResponse(HttpResponse): + """Response serving a file to be downloaded. + """ + def __init__ (self, file_path, file_name, mimetype): + super(AttachmentHttpResponse, self).__init__(mimetype=mimetype) + self['Content-Disposition'] = 'attachment; filename=%s' % file_name + self.file_path = file_path + self.file_name = file_name + + with open(DefaultStorage().path(self.file_path)) as f: + for chunk in read_chunks(f): + self.write(chunk) + @task -def create_zip_task(*args): - return create_zip(*args) +def async_build_pdf(book_id, customizations, file_name): + """ + A celery task to generate pdf files. + Accepts the same args as Book.build_pdf, but with book id as first parameter + instead of Book instance + """ + try: + book = catalogue.models.Book.objects.get(id=book_id) + print "will gen %s" % DefaultStorage().path(file_name) + if not DefaultStorage().exists(file_name): + book.build_pdf(customizations=customizations, file_name=file_name) + print "done." + except Exception, e: + print "Error during pdf creation: %s" % e + print_exc + raise e + + +class MultiQuerySet(object): + def __init__(self, *args, **kwargs): + self.querysets = args + self._count = None + + def count(self): + if not self._count: + self._count = sum(len(qs) for qs in self.querysets) + return self._count + + def __len__(self): + return self.count() + + def __getitem__(self, item): + try: + indices = (offset, stop, step) = item.indices(self.count()) + except AttributeError: + # it's not a slice - make it one + return self[item : item + 1][0] + items = [] + total_len = stop - offset + for qs in self.querysets: + if len(qs) < offset: + offset -= len(qs) + else: + items += list(qs[offset:stop]) + if len(items) >= total_len: + return items + else: + offset = 0 + stop = total_len - len(items) + continue