Using cache middleware instead of various caching micro-strategies,

[wolnelektury.git] / apps / catalogue / utils.py

diff --git a/apps/catalogue/utils.py b/apps/catalogue/utils.py
index 9de4eaa..bcc5a0b 100644 (file)
--- a/apps/catalogue/utils.py
+++ b/apps/catalogue/utils.py
@@ -2,8 +2,8 @@
 # This file is part of Wolnelektury, licensed under GNU Affero GPLv3 or later.
 # Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
 #
 # 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
-
+from collections import defaultdict
+import hashlib

 import random
 import re
 import time
 import random
 import re
 import time


@@ -13,7 +13,6 @@ 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.core.files.uploadedfile import UploadedFile
 from django.core.files.storage import DefaultStorage
 from django.utils.encoding import force_unicode

-from django.utils.hashcompat import sha_constructor

 from django.conf import settings
 from os import mkdir, path, unlink
 from errno import EEXIST, ENOENT
 from django.conf import settings
 from os import mkdir, path, unlink
 from errno import EEXIST, ENOENT


@@ -31,16 +30,27 @@ MAX_SESSION_KEY = 18446744073709551616L     # 2 << 63
 
 
 def get_random_hash(seed):
 
 
 def get_random_hash(seed):

-    sha_digest = sha_constructor('%s%s%s%s' %
+    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()
 
 
         (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):
-    result = {}
-    for tag in tags:
-        result.setdefault(tag.category, []).append(tag)
+def split_tags(*tag_lists):
+    if len(tag_lists) == 1:
+        result = defaultdict(list)
+        for tag in tag_lists[0]:
+            result[tag.category].append(tag)
+    else:
+        result = defaultdict(dict)
+        for tag_list in tag_lists:
+            for tag in tag_list:
+                try:
+                    result[tag.category][tag.pk].count += tag.count
+                except KeyError:
+                    result[tag.category][tag.pk] = tag
+        for k, v in result.items():
+            result[k] = sorted(v.values(), key=lambda tag: tag.sort_key)

     return result
 
 
     return result
 
 


@@ -74,7 +84,7 @@ class LockFile(object):
         try:
             unlink(self.lockname)
         except OSError as oe:
         try:
             unlink(self.lockname)
         except OSError as oe:

-            if oe.errno != oe.EEXIST:
+            if oe.errno != EEXIST:

                 raise oe
         self.lock.close()
 
                 raise oe
         self.lock.close()
 


@@ -125,7 +135,7 @@ def remove_zip(zip_slug):
 class AttachmentHttpResponse(HttpResponse):
     """Response serving a file to be downloaded.
     """
 class AttachmentHttpResponse(HttpResponse):
     """Response serving a file to be downloaded.
     """

-    def __init__ (self, file_path, file_name, mimetype):
+    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
         super(AttachmentHttpResponse, self).__init__(mimetype=mimetype)
         self['Content-Disposition'] = 'attachment; filename=%s' % file_name
         self.file_path = file_path


@@ -139,18 +149,18 @@ class MultiQuerySet(object):
     def __init__(self, *args, **kwargs):
         self.querysets = args
         self._count = None
     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 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 __len__(self):
         return self.count()

-        
+

     def __getitem__(self, item):
         try:
     def __getitem__(self, item):
         try:

-            indices = (offset, stop, step) = item.indices(self.count())
+            (offset, stop, step) = item.indices(self.count())

         except AttributeError:
             # it's not a slice - make it one
             return self[item : item + 1][0]
         except AttributeError:
             # it's not a slice - make it one
             return self[item : item + 1][0]


@@ -168,6 +178,55 @@ class MultiQuerySet(object):
                     stop = total_len - len(items)
                     continue
 
                     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:
+            (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
 
 def truncate_html_words(s, num, end_text='...'):
     """Truncates HTML to a certain number of words (not counting tags and


@@ -257,3 +316,43 @@ def clear_custom_pdf(book):
     """
     from waiter.utils import clear_cache
     clear_cache('book/%s' % book.slug)
     """
     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])