# -*- coding: utf-8 -*-
+# 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 hashlib
+import random
+import re
+import time
+from base64 import urlsafe_b64encode
+
+from django.http import HttpResponse
+from django.core.files.uploadedfile import UploadedFile
+from django.core.files.storage import DefaultStorage
+from django.utils.encoding import force_unicode
+from django.utils.translation import get_language
+from django.conf import settings
+from os import mkdir, path, unlink
+from errno import EEXIST, ENOENT
+from fcntl import flock, LOCK_EX
+from zipfile import ZipFile
+
+from reporting.utils import read_chunks
+
+# Use the system (hardware-based) random number generator if it exists.
+if hasattr(random, 'SystemRandom'):
+ randrange = random.SystemRandom().randrange
+else:
+ randrange = random.randrange
+MAX_SESSION_KEY = 18446744073709551616L # 2 << 63
+
+
+def get_random_hash(seed):
+ sha_digest = hashlib.sha1('%s%s%s%s' %
+ (randrange(0, MAX_SESSION_KEY), time.time(), unicode(seed).encode('utf-8', 'replace'),
+ settings.SECRET_KEY)).digest()
+ return urlsafe_b64encode(sha_digest).replace('=', '').replace('_', '-').lower()
+
+
+def split_tags(tags, initial=None):
+ if initial is None:
+ result = {}
+ else:
+ result = initial
-def split_tags(tags):
- result = {}
for tag in tags:
result.setdefault(tag.category, []).append(tag)
return result
+
+class ExistingFile(UploadedFile):
+
+ def __init__(self, path, *args, **kwargs):
+ self.path = path
+ super(ExistingFile, self).__init__(*args, **kwargs)
+
+ def temporary_file_path(self):
+ return self.path
+
+ def close(self):
+ pass
+
+
+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 != 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
+
+
+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)
+
+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
+
+class SortedMultiQuerySet(MultiQuerySet):
+ def __init__(self, *args, **kwargs):
+ self.order_by = kwargs.pop('order_by', None)
+ self.sortfn = kwargs.pop('sortfn', None)
+ if self.order_by is not None:
+ self.sortfn = lambda a, b: cmp((getattr(a, f) for f in self.order_by),
+ (getattr(b, f) for f in self.order_by))
+ super(SortedMultiQuerySet, self).__init__(*args, **kwargs)
+
+ def __getitem__(self, item):
+ sort_heads = [0] * len(self.querysets)
+ 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
+ skipped = 0
+ i_s = range(len(sort_heads))
+
+ while len(items) < total_len:
+ candidate = None
+ candidate_i = None
+ for i in i_s:
+ def get_next():
+ return self.querysets[i][sort_heads[i]]
+ try:
+ if candidate is None:
+ candidate = get_next()
+ candidate_i = i
+ else:
+ competitor = get_next()
+ if self.sortfn(candidate, competitor) > 0:
+ candidate = competitor
+ candidate_i = i
+ except IndexError:
+ continue # continue next sort_head
+ # we have no more elements:
+ if candidate is None:
+ break
+ sort_heads[candidate_i] += 1
+ if skipped < offset:
+ skipped += 1
+ continue # continue next item
+ items.append(candidate)
+
+ return items
+
+
+def truncate_html_words(s, num, end_text='...'):
+ """Truncates HTML to a certain number of words (not counting tags and
+ comments). Closes opened tags if they were correctly closed in the given
+ html. Takes an optional argument of what should be used to notify that the
+ string has been truncated, defaulting to ellipsis (...).
+
+ Newlines in the HTML are preserved.
+
+ This is just a version of django.utils.text.truncate_html_words with no space before the end_text.
+ """
+ s = force_unicode(s)
+ length = int(num)
+ if length <= 0:
+ return u''
+ html4_singlets = ('br', 'col', 'link', 'base', 'img', 'param', 'area', 'hr', 'input')
+ # Set up regular expressions
+ re_words = re.compile(r'&.*?;|<.*?>|(\w[\w-]*)', re.U)
+ re_tag = re.compile(r'<(/)?([^ ]+?)(?: (/)| .*?)?>')
+ # Count non-HTML words and keep note of open tags
+ pos = 0
+ end_text_pos = 0
+ words = 0
+ open_tags = []
+ while words <= length:
+ m = re_words.search(s, pos)
+ if not m:
+ # Checked through whole string
+ break
+ pos = m.end(0)
+ if m.group(1):
+ # It's an actual non-HTML word
+ words += 1
+ if words == length:
+ end_text_pos = pos
+ continue
+ # Check for tag
+ tag = re_tag.match(m.group(0))
+ if not tag or end_text_pos:
+ # Don't worry about non tags or tags after our truncate point
+ continue
+ closing_tag, tagname, self_closing = tag.groups()
+ tagname = tagname.lower() # Element names are always case-insensitive
+ if self_closing or tagname in html4_singlets:
+ pass
+ elif closing_tag:
+ # Check for match in open tags list
+ try:
+ i = open_tags.index(tagname)
+ except ValueError:
+ pass
+ else:
+ # SGML: An end tag closes, back to the matching start tag, all unclosed intervening start tags with omitted end tags
+ open_tags = open_tags[i+1:]
+ else:
+ # Add it to the start of the open tags list
+ open_tags.insert(0, tagname)
+ if words <= length:
+ # Don't try to close tags if we don't need to truncate
+ return s
+ out = s[:end_text_pos]
+ if end_text:
+ out += end_text
+ # Close any tags still open
+ for tag in open_tags:
+ out += '</%s>' % tag
+ # Return string
+ return out
+
+
+def customizations_hash(customizations):
+ customizations.sort()
+ return hash(tuple(customizations))
+
+
+def get_customized_pdf_path(book, customizations):
+ """
+ Returns a MEDIA_ROOT relative path for a customized pdf. The name will contain a hash of customization options.
+ """
+ h = customizations_hash(customizations)
+ return 'book/%s/%s-custom-%s.pdf' % (book.slug, book.slug, h)
+
+
+def clear_custom_pdf(book):
+ """
+ Returns a list of paths to generated customized pdf of a book
+ """
+ from waiter.utils import clear_cache
+ clear_cache('book/%s' % book.slug)
+
+
+class AppSettings(object):
+ """Allows specyfying custom settings for an app, with default values.
+
+ Just subclass, set some properties and instantiate with a prefix.
+ Getting a SETTING from an instance will check for prefix_SETTING
+ in project settings if set, else take the default. The value will be
+ then filtered through _more_SETTING method, if there is one.
+
+ """
+ def __init__(self, prefix):
+ self._prefix = prefix
+
+ def __getattribute__(self, name):
+ if name.startswith('_'):
+ return object.__getattribute__(self, name)
+ value = getattr(settings,
+ "%s_%s" % (self._prefix, name),
+ object.__getattribute__(self, name))
+ more = "_more_%s" % name
+ if hasattr(self, more):
+ value = getattr(self, more)(value)
+ return value
+
+
+def trim_query_log(trim_to=25):
+ """
+connection.queries includes all SQL statements -- INSERTs, UPDATES, SELECTs, etc. Each time your app hits the database, the query will be recorded.
+This can sometimes occupy lots of memory, so trim it here a bit.
+ """
+ if settings.DEBUG:
+ from django.db import connection
+ connection.queries = trim_to > 0 \
+ and connection.queries[-trim_to:] \
+ or []
+
+
+def delete_from_cache_by_language(cache, key_template):
+ cache.delete_many([key_template % lc for lc, ln in settings.LANGUAGES])
fnp / wolnelektury.git / blobdiff