--- /dev/null
+*~
+*.orig
+*.log
+
+# Python garbage
+*.pyc
+.coverage
+pip-log.txt
+nosetests.xml
+build
+dist
+*.egg-info
+
+# Mac OS X garbage
+.DS_Store
+
+# Windows garbage
+thumbs.db
+
+# Eclipse
+.project
+.settings
+.pydevproject
+.tmp_*
+
+# Tags file
+TAGS
+
--- /dev/null
+ GNU AFFERO GENERAL PUBLIC LICENSE
+ Version 3, 19 November 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
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+SUCH DAMAGES.
+
+ 17. Interpretation of Sections 15 and 16.
+
+ If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+ END OF TERMS AND CONDITIONS
+
+ How to Apply These Terms to Your New Programs
+
+ If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+ To do so, attach the following notices to the program. It is safest
+to attach them to the start of each source file to most effectively
+state the exclusion of warranty; and each file should have at least
+the "copyright" line and a pointer to where the full notice is found.
+
+ <one line to give the program's name and a brief idea of what it does.>
+ Copyright (C) <year> <name of author>
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper mail.
+
+ If your software can interact with users remotely through a computer
+network, you should also make sure that it provides a way for users to
+get its source. For example, if your program is a web application, its
+interface could display a "Source" link that leads users to an archive
+of the code. There are many ways you could offer source, and different
+solutions will be better for different programs; see section 13 for the
+specific requirements.
+
+ You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary.
+For more information on this, and how to apply and follow the GNU AGPL, see
+<http://www.gnu.org/licenses/>.
\ No newline at end of file
--- /dev/null
+include LICENSE
+include README.md
+recursive-include ssify/templates *.html
+recursive-include tests/templates *.html
--- /dev/null
+License
+-------
+
+ ![AGPL Logo](http://www.gnu.org/graphics/agplv3-155x51.png)
+
+ Copyright © 2014 Fundacja Nowoczesna Polska <fundacja@nowoczesnapolska.org.pl>
+
+ For full list of contributors see AUTHORS section at the end.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU Affero General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU Affero General Public License for more details.
+
+ You should have received a copy of the GNU Affero General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+
+Dependencies
+============
+
+ * Python >= 2.7
+ * Django >= 1.6
+
+
+Installation
+============
+
+1. Add 'ssify' to INSTALLES_APPS.
+2. Add middleware classes:
+ * ssify.middleware.SsifyMiddleware on top,
+ * if using UpdateCacheMiddleware, add
+ ssify.middleware.PrepareForCacheMiddleware after it,
+ * ssify.middleware.LocaleMiddleware instead of stock LocaleMiddleware.
+3. Make sure you have 'django.core.context_processors.request' in your
+ TEMPLATE_CONTEXT_PROCESSORS.
+3. Define your caches in CACHES and SSIFY_INCLUDES_CACHES
+ for storing ssi includes.
+4. Configure your webserver to use SSI ('ssi=on' with Nginx).
+
+Usage
+=====
+
+1. Define your included urls using the @ssi_included decorator.
+2. Define your ssi variables using the @ssi_variable decorator.
+
+
+Authors
+=======
+
+* Radek Czajka <radekczajka@nowoczesnapolska.org.pl>
+
--- /dev/null
+#!/usr/bin/env python
+import sys
+import os
+from os.path import dirname, abspath
+from optparse import OptionParser
+
+from django.conf import settings, global_settings
+
+# For convenience configure settings if they are not pre-configured or if we
+# haven't been provided settings to use by environment variable.
+if not settings.configured and not os.environ.get('DJANGO_SETTINGS_MODULE'):
+ settings.configure(
+ CACHES={
+ 'default': {'BACKEND':
+ 'django.core.cache.backends.locmem.LocMemCache'},
+ 'ssify': {'BACKEND':
+ 'django.core.cache.backends.locmem.LocMemCache'},
+ },
+ DATABASES={
+ 'default': {
+ 'ENGINE': 'django.db.backends.sqlite3',
+ }
+ },
+ INSTALLED_APPS=[
+ 'django.contrib.auth',
+ 'django.contrib.contenttypes',
+ 'django.contrib.sessions',
+ 'django.contrib.sites',
+
+ 'ssify',
+ 'tests',
+ ],
+ MEDIA_URL='/media/',
+ MIDDLEWARE_CLASSES=[
+ 'ssify.middleware.SsiMiddleware',
+ 'django.middleware.cache.UpdateCacheMiddleware',
+ 'ssify.middleware.PrepareForCacheMiddleware',
+ 'django.middleware.common.CommonMiddleware',
+ 'django.middleware.cache.FetchFromCacheMiddleware',
+ ],
+ STATIC_URL='/static/',
+ ROOT_URLCONF='tests.urls',
+ SITE_ID=1,
+ SSIFY_DEBUG_VERBOSE=False,
+ TEMPLATE_CONTEXT_PROCESSORS=(
+ "django.core.context_processors.debug",
+ "django.core.context_processors.i18n",
+ "django.core.context_processors.tz",
+ "django.core.context_processors.request",
+ ),
+ )
+
+from django.test.simple import DjangoTestSuiteRunner
+
+
+def runtests(*test_args, **kwargs):
+ if 'south' in settings.INSTALLED_APPS:
+ from south.management.commands import patch_for_test_db_setup
+ patch_for_test_db_setup()
+
+ if not test_args:
+ test_args = ['tests']
+ parent = dirname(abspath(__file__))
+ sys.path.insert(0, parent)
+ test_runner = DjangoTestSuiteRunner(
+ verbosity=kwargs.get('verbosity', 1),
+ interactive=kwargs.get('interactive', False),
+ failfast=kwargs.get('failfast'))
+ failures = test_runner.run_tests(test_args)
+ sys.exit(failures)
+
+if __name__ == '__main__':
+ parser = OptionParser()
+ parser.add_option('--failfast', action='store_true',
+ default=False, dest='failfast')
+
+ (options, args) = parser.parse_args()
+
+ runtests(failfast=options.failfast, *args)
--- /dev/null
+#!/usr/bin/env python
+# -*- coding: utf-8 -*-
+#
+from setuptools import setup, find_packages
+
+setup(
+ name='django-ssify',
+ version='0.1',
+ author='Radek Czajka',
+ author_email='radekczajka@nowoczesnapolska.org.pl',
+ url='',
+ packages=find_packages(exclude=['tests*']),
+ license='LICENSE',
+ description='Two-phased rendering using SSI.',
+ long_description=open('README.md').read(),
+ test_suite="runtests.runtests",
+ classifiers=[
+ "Development Status :: 3 - Alpha",
+ "Environment :: Web Environment",
+ "Framework :: Django",
+ "Intended Audience :: Developers",
+ "Intended Audience :: System Administrators",
+ "License :: OSI Approved :: GNU Affero General Public License v3",
+ "Programming Language :: Python",
+ "Topic :: Internet :: WWW/HTTP",
+ "Topic :: Software Development :: Code Generators",
+ ]
+)
--- /dev/null
+"""
+Implements two-phase rendering using SSI statements.
+
+Define reqest-dependent SSI variables to use as template tags
+with `ssi_variable` decorator.
+
+Define views to be cached and included as SSI include
+with `ssi_included` decorator.
+
+"""
+
+__version__ = '1.0'
+__date__ = '2014-08-26'
+__all__ = ('ssi_expect', 'SsiVariable', 'ssi_included', 'ssi_variable')
+
+from django.conf import settings
+from django.utils.functional import lazy
+
+SETTING = lazy(
+ lambda name, default: getattr(settings, name, default),
+ bool, int, list, tuple, unicode)
+
+INCLUDES_CACHES = SETTING('SSIFY_INCLUDES_CACHES', ('ssify',))
+DEBUG = SETTING('SSIFY_DEBUG', False)
+DEBUG_VERBOSE = SETTING('SSIFY_DEBUG_VERBOSE', True)
+
+
+from .variables import ssi_expect, SsiVariable
+from .decorators import ssi_included, ssi_variable
--- /dev/null
+import os
+from django.core.cache.backends.filebased import FileBasedCache
+
+
+class StaticFileBasedCache(FileBasedCache):
+ def __init__(self, *args, **kwargs):
+ super(StaticFileBasedCache, self).__init__(*args, **kwargs)
+ self._dir = os.path.abspath(self._dir)
+
+ def make_key(self, key, version=None):
+ assert version is None, \
+ 'StaticFileBasedCache does not support versioning.'
+ return key
+
+ def _key_to_file(self, key):
+ key = os.path.abspath(os.path.join(self._dir, key.lstrip('/')))
+ assert key.startswith(self._dir), 'Trying to save path outside root.'
+ if key.endswith('/'):
+ key += 'index.html'
+ return key
+
+ def get(self, key, default=None, version=None):
+ key = self.make_key(key, version=version)
+ self.validate_key(key)
+ fname = self._key_to_file(key)
+ try:
+ with open(fname, 'rb') as inf:
+ return inf.read()
+ except (IOError, OSError):
+ pass
+ return default
+
+ def set(self, key, value, timeout=None, version=None):
+ assert timeout is None, \
+ 'StaticFileBasedCache does not support timeouts.'
+ key = self.make_key(key, version=version)
+ self.validate_key(key)
+ fname = self._key_to_file(key)
+ dirname = os.path.dirname(fname)
+ try:
+ if not os.path.exists(dirname):
+ os.makedirs(dirname)
+ with open(fname, 'wb') as outf:
+ outf.write(value)
+ except (IOError, OSError):
+ pass
--- /dev/null
+import functools
+from inspect import getargspec
+import warnings
+from django.template.base import parse_bits
+from django.utils.translation import get_language, activate
+from .store import cache_include
+from . import exceptions
+from .variables import SsiVariable
+
+
+def ssi_included(view=None, use_lang=True, get_ssi_vars=None):
+ """
+ Marks a view to be used as a snippet to be included with SSI.
+
+ If use_lang is True (which is default), the URL pattern for such
+ a view must provide a keyword argument named 'lang' for language.
+ SSI included views don't use language or content negotiation, so
+ everything they need to know has to be included in the URL.
+
+ get_ssi_vars should be a callable which takes the view's arguments
+ and returns the names of SSI variables it uses.
+
+ """
+ def dec(view):
+ @functools.wraps(view)
+ def new_view(request, *args, **kwargs):
+ if use_lang:
+ try:
+ lang = kwargs.pop('lang')
+ except KeyError:
+ raise exceptions.NoLangFieldError(request)
+ current_lang = get_language()
+ activate(lang)
+ response = view(request, *args, **kwargs)
+ if use_lang:
+ activate(current_lang)
+ if response.status_code == 200:
+ request._cache_update_cache = False
+
+ def _check_included_vars(response):
+ used_vars = request.ssi_vars_needed
+ if get_ssi_vars:
+ # Remove the ssi vars that should be provided
+ # by the including view.
+ pass_vars = set(get_ssi_vars(*args, **kwargs))
+
+ for var in pass_vars:
+ if not isinstance(var, SsiVariable):
+ var = SsiVariable(*var)
+ try:
+ del used_vars[var.name]
+ except KeyError:
+ warnings.warn(
+ exceptions.UnusedSsiVarsWarning(
+ request, var))
+ if used_vars:
+ raise exceptions.UndeclaredSsiVarsError(
+ request, used_vars)
+ request.ssi_vars_needed = {}
+
+ # Don't use default django response caching for this view,
+ # just save the contents instead.
+ cache_include(request.path, response.content)
+
+ if hasattr(response, 'render') and callable(response.render):
+ response.add_post_render_callback(_check_included_vars)
+ else:
+ _check_included_vars(response)
+
+ return response
+
+ # Remember get_ssi_vars so that in can be computed from args/kwargs
+ # by including view.
+ new_view.get_ssi_vars = get_ssi_vars
+ return new_view
+ return dec(view) if view else dec
+
+
+def ssi_variable(register, vary=None, name=None):
+ # Cache control?
+ def dec(func):
+ # Find own path.
+ function_name = (name or
+ getattr(func, '_decorated_function', func).__name__)
+ lib_name = func.__module__.rsplit('.', 1)[-1]
+ tagpath = "%s.%s" % (lib_name, function_name)
+ # Make sure the function takes request parameter.
+ params, varargs, varkw, defaults = getargspec(func)
+ assert params and params[0] == 'request', '%s is decorated with '\
+ 'request_info_tag, so it must take `request` for '\
+ 'its first argument.' % (tagpath)
+
+ @register.tag(name=function_name)
+ def _ssi_var_tag(parser, token):
+ """
+ Creates a SSI variable reference for a request-dependent info.
+
+ Use as:
+ {% ri_tag args... %}
+ or:
+ {% ri_tag args... as variable %}
+ {{ variable.if }}
+ {{ variable }}, or
+ {% ssi_include 'some-snippet' variable %}
+ {{ variable.else }}
+ Default text
+ {{ variable.endif }}
+
+ """
+ bits = token.split_contents()[1:]
+
+ # Is it the 'as' form?
+ if len(bits) >= 2 and bits[-2] == 'as':
+ asvar = bits[-1]
+ bits = bits[:-2]
+ else:
+ asvar = None
+
+ # Parse the arguments like Django's generic tags do.
+ args, kwargs = parse_bits(parser, bits,
+ ['context'] + params[1:], varargs, varkw,
+ defaults, takes_context=True,
+ name=function_name)
+ return SsiVariableNode(tagpath, args, kwargs, vary, asvar)
+ _ssi_var_tag.get_value = func
+ #return _ssi_var_tag
+ return func
+
+ return dec
+
+
+from .variables import SsiVariableNode
--- /dev/null
+class SsifyError(BaseException):
+ pass
+
+
+class SsifyWarning(Warning):
+ pass
+
+
+class UndeclaredSsiVarsError(SsifyError):
+ def __init__(self, request, ssi_vars):
+ super(UndeclaredSsiVarsError, self).__init__(request, ssi_vars)
+
+ def __str__(self):
+ request = self.args[0]
+ view = request.resolver_match.func
+ return "The view '%s.%s' at '%s' is marked as `ssi_included`, "\
+ "but it uses ssi variables not declared in `get_ssi_vars` "\
+ "argument: %s. " % (
+ view.__module__, view.__name__, request.path,
+ repr(self.args[1]))
+
+
+class UnusedSsiVarsWarning(SsifyWarning):
+ def __init__(self, request, ssi_vars):
+ super(UnusedSsiVarsWarning, self).__init__(request, ssi_vars)
+
+ def __str__(self):
+ request = self.args[0]
+ view = request.resolver_match.func
+ return "The `ssi_included` view '%s.%s' at '%s' declares "\
+ "using SSI variables %s but it looks like they're not "\
+ "really used. " % (
+ view.__module__, view.__name__, request.path, self.args[1])
+
+
+class UndeclaredSsiRefError(SsifyError):
+ def __init__(self, request, var, ref_name):
+ super(UndeclaredSsiRefError, self).__init__(request, var, ref_name)
+
+ def __str__(self):
+ request = self.args[0]
+ view = request.resolver_match.func
+ return "Error while rendering ssi_included view '%s.%s' at '%s': "\
+ "SSI variable %s references variable %s, which doesn't match "\
+ "any variable declared in `get_ssi_vars`. " % (
+ view.__module__, view.__name__, request.path,
+ repr(self.args[1]), self.args[2])
+
+
+class NoLangFieldError(SsifyError):
+ def __init__(self, request):
+ super(NoLangFieldError, self).__init__(request)
+
+ def __str__(self):
+ request = self.args[0]
+ view = request.resolver_match.func
+ return "The view '%s.%s' at '%s' is marked as `ssi_included` "\
+ "with use_lang=True, but its URL match doesn't provide "\
+ "a 'lang' keyword argument for language. " % (
+ view.__module__, view.__name__, request.path)
+
+
+class SsiVarsDependencyCycleError(SsifyError):
+ def __init__(self, ssi_vars):
+ super(SsiVarsDependencyCycleError, self).__init__(ssi_vars)
+
+ def __str__(self):
+ return "Dependency cycle in SSI variables: %s." % self.args[0]
--- /dev/null
+# -*- 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 optparse import make_option
+from django.core.management.base import BaseCommand
+
+
+class Command(BaseCommand):
+ option_list = BaseCommand.option_list + (
+ )
+ help = 'Dumps configuration for NGINX.'
+
+ def handle(self, **options):
+ pass
--- /dev/null
+from django.conf import settings
+from django.utils.cache import patch_vary_headers
+from django.middleware import locale
+from .serializers import json_decode, json_encode
+from .variables import SsiVariable, provide_vars
+from . import DEBUG
+
+
+class PrepareForCacheMiddleware(object):
+ @staticmethod
+ def process_response(request, response):
+ if getattr(request, 'ssi_vars_needed', None):
+ vars_needed = {k: v.definition
+ for (k, v) in request.ssi_vars_needed.items()}
+ response['X-Ssi-Vars-Needed'] = json_encode(
+ vars_needed, sort_keys=True)
+ return response
+
+
+class SsiMiddleware(object):
+ def process_request(self, request):
+ request.ssi_vary = set()
+ #request.ssi_cache_control_after = set()
+
+ def process_view(self, request, view_func, view_args, view_kwargs):
+ request.ssi_vars_needed = {}
+
+ def _process_rendered_response(self, request, response):
+ # Prepend the SSI variables.
+ if hasattr(request, 'ssi_vars_needed'):
+ vars_needed = request.ssi_vars_needed
+ else:
+ vars_needed = json_decode(response.get('X-Ssi-Vars-Needed', '{}'))
+ vars_needed = {k: SsiVariable(*v)
+ for (k, v) in vars_needed.items()}
+
+ if vars_needed:
+ response.content = provide_vars(request, vars_needed) + \
+ response.content
+
+ # Add the Vary headers declared by all the SSI vars.
+ patch_vary_headers(response, sorted(request.ssi_vary))
+ # TODO: cache control?
+
+ # With a cached response, CsrfViewMiddleware.process_response
+ # was never called, so if we used the csrf token, we must do
+ # its job of setting the csrf token cookie on our own.
+ if (not getattr(request, 'csrf_processing_done', False)
+ and request.META.get("CSRF_COOKIE_USED", False)):
+ response.set_cookie(settings.CSRF_COOKIE_NAME,
+ request.META["CSRF_COOKIE"],
+ max_age=getattr(settings, 'CSRF_COOKIE_AGE',
+ 60 * 60 * 24 * 7 * 52),
+ domain=settings.CSRF_COOKIE_DOMAIN,
+ path=settings.CSRF_COOKIE_PATH,
+ secure=settings.CSRF_COOKIE_SECURE,
+ httponly=settings.CSRF_COOKIE_HTTPONLY
+ )
+ request.csrf_processing_done = True
+
+ def process_response(self, request, response):
+ if hasattr(response, 'render') and callable(response.render):
+ response.add_post_render_callback(
+ lambda r: self._process_rendered_response(request, r)
+ )
+ else:
+ self._process_rendered_response(request, response)
+
+ if DEBUG:
+ from .middleware_debug import DebugUnSsiMiddleware
+ response = DebugUnSsiMiddleware().process_response(
+ request, response)
+
+ return response
+
+
+class LocaleMiddleware(locale.LocaleMiddleware):
+ """
+ Version of the LocaleMiddleware for use together with the
+ SsiMiddleware if USE_I18N or USE_L10N is set.
+
+ Stock LocaleMiddleware looks for user language selection in
+ the session data and cookies, before it falls back to parsing
+ Accept-Language. The effect of accessing the session is adding
+ the `Vary: Cookie` header to the response. While this is correct
+ behaviour, it renders the cache system useless (see
+ https://code.djangoproject.com/ticket/13217).
+
+ This version of LocaleMiddleware doesn't mark the session
+ as accessed on every request, so SessionMiddleware doesn't add the
+ Vary: Cookie header (unless something else actually uses the session
+ in a meaningful way, of course). Instead, it tells SsiMiddleware
+ to add the Vary: Cookie header to the final response.
+
+ """
+ def process_request(self, request):
+ if hasattr(request, 'session'):
+ session_accessed_before = request.session.accessed
+ else:
+ session_accessed_before = None
+ super(LocaleMiddleware, self).process_request(request)
+ if session_accessed_before is False:
+ if (request.session.accessed and
+ (settings.USE_I18N or settings.USE_L10N)):
+ request.session.accessed = False
+ request.ssi_vary.add('Cookie')
--- /dev/null
+"""
+This module should only be used for debugging SSI statements.
+
+Using DebugUnSsiMiddleware in production defeats the purpose of using SSI
+in the first place, and is unsafe. You should use a proper webserver with SSI
+support as a proxy (i.e. Nginx with ssi=on).
+
+"""
+import re
+import urlparse
+from django.core.urlresolvers import resolve
+from ssify import DEBUG_VERBOSE
+
+
+SSI_SET = re.compile(r"<!--#set var='(?P<var>[^']+)' "
+ r"value='(?P<value>|\\\\|.*?[^\\](?:\\\\)*)'-->", re.S)
+SSI_ECHO = re.compile(r"<!--#echo var='(?P<var>[^']+)' encoding='none'-->")
+SSI_INCLUDE = re.compile(r"<!--#include (?:virtual|file)='(?P<path>[^']+)'-->")
+SSI_IF = re.compile(r"(?P<header><!--#if expr='(?P<expr>[^']*)'-->)"
+ r"(?P<value>.*?)(?:<!--#else-->(?P<else>.*?))?"
+ r"<!--#endif-->", re.S)
+ # TODO: escaped?
+SSI_VAR = re.compile(r"\$\{(?P<var>.+)\}") # TODO: escaped?
+
+
+class DebugUnSsiMiddleware(object):
+ """
+ Emulates a webserver with SSI support.
+
+ This middleware should only be used for debugging purposes.
+ SsiMiddleware will enable it automatically, if SSIFY_DEBUG setting
+ is set to True, so you don't normally need to include it in
+ MIDDLEWARE_CLASSES.
+
+ If SSIFY_DEBUG_VERBOSE setting is True, it will also leave some
+ information in HTML comments.
+
+ """
+ @staticmethod
+ def _process_rendered_response(request, response):
+ """Recursively process SSI statements in the response."""
+ def ssi_include(match):
+ """Replaces SSI include with contents rendered by relevant view."""
+ path = process_value(match.group('path'))
+ func, args, kwargs = resolve(path)
+ parsed = urlparse.urlparse(path)
+ request.META['PATH_INFO'] = request.path_info = \
+ request.path = parsed.path
+ request.META['QUERY_STRING'] = parsed.query
+ content = func(request, *args, **kwargs).content
+ content = process_content(content)
+ if DEBUG_VERBOSE:
+ return "".join((
+ match.group(0),
+ content,
+ match.group(0).replace('<!--#', '<!--#end-'),
+ ))
+ else:
+ return content
+
+ def ssi_set(match):
+ """Interprets SSI set statement."""
+ variables[match.group('var')] = match.group('value')
+ if DEBUG_VERBOSE:
+ return match.group(0)
+ else:
+ return ""
+
+ def ssi_echo(match):
+ """Interprets SSI echo, outputting the value of the variable."""
+ content = variables[match.group('var')]
+ if DEBUG_VERBOSE:
+ return "".join((
+ match.group(0),
+ content,
+ match.group(0).replace('<!--#', '<!--#end-'),
+ ))
+ else:
+ return content
+
+ def ssi_if(match):
+ """Interprets SSI if statement."""
+ expr = process_value(match.group('expr'))
+ if expr:
+ content = match.group('value')
+ else:
+ content = match.group('else')
+ if DEBUG_VERBOSE:
+ return "".join((
+ match.group('header'),
+ content,
+ match.group('header').replace('<!--#', '<!--#end-'),
+ ))
+ else:
+ return content
+
+ def ssi_var(match):
+ """Resolves ${var}-style variable reference."""
+ return variables[match.group('var')]
+
+ def process_value(content):
+ """Resolves any ${var}-style variable references in the content."""
+ return re.sub(SSI_VAR, ssi_var, content)
+
+ def process_content(content):
+ """Interprets SSI statements in the content."""
+ content = re.sub(SSI_SET, ssi_set, content)
+ content = re.sub(SSI_ECHO, ssi_echo, content)
+ content = re.sub(SSI_IF, ssi_if, content)
+ content = re.sub(SSI_INCLUDE, ssi_include, content)
+ return content
+
+ variables = {}
+ response.content = process_content(response.content)
+ response['Content-Length'] = len(response.content)
+
+ def process_response(self, request, response):
+ """Support for unrendered responses."""
+ if hasattr(response, 'render') and callable(response.render):
+ response.add_post_render_callback(
+ lambda r: self._process_rendered_response(request, r)
+ )
+ else:
+ self._process_rendered_response(request, response)
+ return response
--- /dev/null
+import json
+from .variables import SsiVariable, SsiExpect
+
+
+def _json_default(o):
+ if isinstance(o, SsiVariable):
+ return {'__var__': o.name}
+ if isinstance(o, SsiExpect):
+ return {'__expect__': o.name}
+ raise TypeError(o, 'not JSON serializable')
+
+
+def _json_obj_hook(obj):
+ if obj.keys() == ['__var__']:
+ return SsiVariable(name=obj['__var__'])
+ if obj.keys() == ['__expect__']:
+ return SsiExpect(obj['__expect__'])
+ return obj
+
+
+def json_encode(obj, **kwargs):
+ return json.JSONEncoder(
+ default=_json_default,
+ separators=(',', ':'),
+ **kwargs).encode(obj)
+
+
+def json_decode(data, **kwargs):
+ return json.loads(data, object_hook=_json_obj_hook, **kwargs)
--- /dev/null
+from django.utils.cache import get_cache
+from ssify import INCLUDES_CACHES
+
+
+includes_caches = [get_cache(c) for c in INCLUDES_CACHES]
+
+
+def cache_include(path, content):
+ for cache in includes_caches:
+ cache.set(path, content)
--- /dev/null
+{% load get_csrf_token from ssify %}<input type='hidden' name='csrfmiddlewaretoken' value='{% get_csrf_token %}' />
--- /dev/null
+# -*- 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 absolute_import
+from django.conf import settings
+from django.core.urlresolvers import NoReverseMatch, reverse, resolve
+from django.middleware.csrf import get_token, rotate_token, _sanitize_token
+from django import template
+from django.utils.translation import get_language
+from ssify.decorators import ssi_variable
+from ssify.variables import SsiVariable
+
+
+register = template.Library()
+
+
+@register.simple_tag(takes_context=True)
+def ssi_include(context, name_, **kwargs):
+ """
+ Inserts an SSI include statement for an URL.
+
+ Works similarly to {% url %}, but only use keyword arguments are
+ supported.
+
+ In addition to just outputting the SSI include statement, it
+ remembers any request-info the included piece declares as needed.
+
+ """
+ b_kwargs = {'lang': get_language()}
+ subst = {}
+ num = 0
+ for k, value in kwargs.items():
+ if isinstance(value, SsiVariable):
+ numstr = '%04d' % num
+ b_kwargs[k] = numstr
+ subst[numstr] = value
+ num += 1
+ else:
+ b_kwargs[k] = value
+
+ try:
+ url = reverse(name_, kwargs=b_kwargs)
+ except NoReverseMatch:
+ b_kwargs.pop('lang')
+ url = reverse(name_, kwargs=b_kwargs)
+ view = resolve(url).func
+
+ for numstr, orig in subst.items():
+ url = url.replace(numstr, orig.as_var())
+ request = context['request']
+
+ # Remember the SSI vars the included view says it needs.
+ get_ssi_vars = getattr(view, 'get_ssi_vars', None)
+ if get_ssi_vars:
+ pass_vars = get_ssi_vars(**kwargs)
+ for var in pass_vars:
+ if not isinstance(var, SsiVariable):
+ var = SsiVariable(*var)
+ request.ssi_vars_needed[var.name] = var
+
+ # Output the SSI include.
+ return "<!--#include file='%s'-->" % url
+
+
+@ssi_variable(register, vary=('Cookie',))
+def get_csrf_token(request):
+ """
+ As CsrfViewMiddleware.process_view is never for a cached response,
+ and we still need to provide a request-specific CSRF token as
+ request-info ssi variable, we must make sure here that the
+ CSRF token is in request.META['CSRF_COOKIE'].
+
+ """
+ token = get_token(request)
+ if token:
+ # CSRF token is already in place, just return it.
+ return token
+
+ # Mimicking CsrfViewMiddleware.process_view.
+ try:
+ token = _sanitize_token(request.COOKIES[settings.CSRF_COOKIE_NAME])
+ request.META['CSRF_COOKIE'] = token
+ except KeyError:
+ # Create new CSRF token.
+ rotate_token(request)
+ token = get_token(request)
+
+ return token
+
+
+@register.inclusion_tag('ssify/csrf_token.html', takes_context=True)
+def csrf_token(context):
+ return {'request': context['request']}
--- /dev/null
+"""
+Utilities for defining SSI variables.
+
+SSI variables are a way of providing values that need to be computed
+at request time to the prerendered templates.
+
+"""
+from hashlib import md5
+from django import template
+from django.utils.encoding import force_unicode
+from django.utils.functional import Promise
+from django.utils.safestring import mark_safe
+from .exceptions import SsiVarsDependencyCycleError, UndeclaredSsiRefError
+
+
+class SsiVariable(object):
+ """
+ Represents a variable computed by a template tag with given arguments.
+
+ Instance of this class is returned from any template tag created
+ with `decorators.ssi_variable` decorator. If renders as SSI echo
+ statement, but you can also use it as an argument to {% ssi_include %},
+ to other ssi_variable, or create SSI if statements by using
+ its `if`, `else`, `endif` properties.
+
+ Variable's name, as used in SSI statements, is a hash of its definition,
+ so the user never has to deal with it directly.
+
+ """
+ ret_types = 'bool', 'int', 'unicode'
+
+ def __init__(self, tagpath=None, args=None, kwargs=None, name=None):
+ self.tagpath = tagpath
+ self.args = list(args or [])
+ self.kwargs = kwargs or {}
+ self._name = name
+
+ @property
+ def name(self):
+ """Variable name is a hash of its definition."""
+ if self._name is None:
+ self._name = 'v' + md5(json_encode(self.definition)).hexdigest()
+ return self._name
+
+ def rehash(self):
+ """
+ Sometimes there's a need to reset the variable name.
+
+ Typically, this is the case after finding real values for
+ variables passed as arguments to {% ssi_include %}.
+ """
+ self._name = None
+ return self.name
+
+ @property
+ def definition(self):
+ """Variable is defined by path to template tag and its arguments."""
+ if self.kwargs:
+ return self.tagpath, self.args, self.kwargs
+ elif self.args:
+ return self.tagpath, self.args
+ else:
+ return self.tagpath,
+
+ def __repr__(self):
+ return "SsiVariable(%s: %s)" % (self.name, repr(self.definition))
+
+ def get_value(self, request):
+ """Computes the real value of the variable, using the request."""
+ taglib, tagname = self.tagpath.rsplit('.', 1)
+ return template.get_library(taglib).tags[tagname].get_value(
+ request, *self.args, **self.kwargs)
+
+ def __unicode__(self):
+ return mark_safe("<!--#echo var='%s' encoding='none'-->" % self.name)
+
+ def as_var(self):
+ """Returns the form that can be used in SSI include's URL."""
+ return '${%s}' % self.name
+
+# If-else-endif properties for use in templates.
+setattr(SsiVariable, 'if',
+ lambda self: mark_safe("<!--#if expr='${%s}'-->" % self.name))
+setattr(SsiVariable, 'else',
+ staticmethod(lambda: mark_safe("<!--#else-->")))
+setattr(SsiVariable, 'endif',
+ staticmethod(lambda: mark_safe('<!--#endif-->')))
+
+
+class SsiExpect(object):
+ """This class says: I want the real value of this variable here."""
+ def __init__(self, name):
+ self.name = name
+
+
+def ssi_expect(var, type_):
+ """
+ Helper function for defining get_ssi_vars on ssi_included views.
+
+ The view needs a way of calculating all the needed variables from
+ the view args. But the args are probably the wrong type
+ (typically, str instead of int) or even are SsiVariables, not
+ resolved until request time.
+
+ This function provides a way to expect a real value of the needed type.
+
+ """
+ if isinstance(var, SsiVariable):
+ return SsiExpect(var.name)
+ else:
+ return type_(var)
+
+
+class SsiVariableNode(template.Node):
+ """ Node for the SsiVariable tags. """
+ def __init__(self, tagpath, args, kwargs, vary=None, asvar=None):
+ self.tagpath = tagpath
+ self.args = args
+ self.kwargs = kwargs
+ self.vary = vary
+ self.asvar = asvar
+
+ def __repr__(self):
+ return "<SsiVariableNode>"
+
+ def render(self, context):
+ """Renders the tag as SSI echo or sets the context variable."""
+ resolved_args = [var.resolve(context) for var in self.args]
+ resolved_kwargs = dict((k, v.resolve(context))
+ for k, v in self.kwargs.items())
+ var = SsiVariable(self.tagpath, resolved_args, resolved_kwargs)
+
+ request = context['request']
+ request.ssi_vars_needed[var.name] = var
+ if self.vary:
+ request.ssi_vary.update(self.vary)
+
+ if self.asvar:
+ context.dicts[0][self.asvar] = var
+ return ''
+ else:
+ return var
+
+
+def ssi_set_statement(var, value):
+ """Generates an SSI set statement for a variable."""
+ if isinstance(value, Promise):
+ # Yes, this is quite brutal. But we need to know
+ # the real value now, we don't know the type,
+ # and we only want to evaluate the lazy function once.
+ value = value._proxy____cast()
+ if value is False or value is None:
+ value = ''
+ return "<!--#set var='%s' value='%s'-->" % (
+ var,
+ force_unicode(value).replace(u'\\', u'\\\\').replace(u"'", u"\\'"))
+
+
+def provide_vars(request, ssi_vars):
+ """
+ Provides all the SSI set statements for ssi_vars variables.
+
+ The main purpose of this function is to by called by SsifyMiddleware.
+ """
+ resolved = {}
+ queue = ssi_vars.items()
+ unresolved_streak = 0
+ while queue:
+ var_name, var = queue.pop(0)
+ hash_dirty = False
+ new_name = var_name
+
+ try:
+ for i, arg in enumerate(var.args):
+ if isinstance(arg, SsiExpect):
+ var.args[i] = resolved[arg.name]
+ hash_dirty = True
+ for k, arg in var.kwargs.items():
+ if isinstance(arg, SsiExpect):
+ var.args[k] = resolved[arg.name]
+ hash_dirty = True
+
+ if hash_dirty:
+ # Rehash after calculating the SsiExpects with real
+ # values, because that's what the included views expect.
+ new_name = var.rehash()
+
+ for i, arg in enumerate(var.args):
+ if isinstance(arg, SsiVariable):
+ var.args[i] = resolved[arg.name]
+ for k, arg in var.kwargs.items():
+ if isinstance(arg, SsiVariable):
+ var.args[k] = resolved[arg.name]
+
+ except KeyError:
+ queue.append((var_name, var))
+ unresolved_streak += 1
+ if unresolved_streak == len(queue):
+ if arg.name in ssi_vars:
+ raise SsiVarsDependencyCycleError(queue)
+ else:
+ raise UndeclaredSsiRefError(request, var, arg.name)
+ continue
+
+ resolved[new_name] = var.get_value(request)
+ unresolved_streak = 0
+
+ output = u"".join(ssi_set_statement(var, value)
+ for (var, value) in resolved.items()
+ ).encode('utf-8')
+ return output
+
+
+from .serializers import json_encode
--- /dev/null
+{% load ssify %}
+
+{% ssi_include 'random_quote' %}
\ No newline at end of file
--- /dev/null
+{% load test_tags %}{% random_number 1 %}
\ No newline at end of file
--- /dev/null
+{% load test_tags %}
+{% quote_len_odd number as odd %}
+{{ quote }}
+Line {{ number }} of {% number_of_quotes %}
+{{ odd.if }}Odd number of characters.
+{{ odd.else }}Even number of characters.
+{{ odd.endif }}
--- /dev/null
+{% load ssify test_tags %}
+{% number_of_quotes as qlen %}
+{% random_number qlen as number %}
+{% ssi_include 'quote' number=number %}
\ No newline at end of file
--- /dev/null
+from django import template
+from ssify import ssi_variable
+from tests.views import QUOTES
+
+register = template.Library()
+
+
+@ssi_variable(register)
+def random_number(request, limit):
+ # Guaranteed to be random as of XKCD#221
+ return min(limit - 1, 4)
+
+
+@ssi_variable(register)
+def number_of_quotes(request):
+ return len(QUOTES)
+
+
+@ssi_variable(register)
+def quote_len_odd(request, which):
+ return bool(len(QUOTES[which]) % 1)
--- /dev/null
+from django.test import Client, TestCase
+from django.test.utils import override_settings
+
+
+class SsifyTestCase(TestCase):
+ def setUp(self):
+ self.client = Client()
+
+ def test_zero(self):
+ self.assertEqual(
+ self.client.get('/number_zero').content,
+ "<!--#set var='ve023a08d2c2075118e25b5f4339438dc' value='0'-->"
+ "<!--#echo var='ve023a08d2c2075118e25b5f4339438dc' "
+ "encoding='none'-->"
+ )
+
+ def test_single_quote(self):
+ self.assertEqual(
+ self.client.get('/quote/3').content.strip(),
+ """Explicit is better than implicit.
+Line 3 of <!--#echo var='va50d914691ecf9b421c680d93ba1263e' encoding='none'-->
+<!--#if expr='${vddc386e120ab274a980ab67384391a1a}'-->Odd number of characters.
+<!--#else-->Even number of characters.
+<!--#endif-->"""
+ )
+
+ def test_random_quote(self):
+ self.assertEqual(
+ self.client.get('/').content.strip(),
+ "<!--#set var='vda0df841702ea993b36d101460264364' value='4'-->"
+ "<!--#set var='va50d914691ecf9b421c680d93ba1263e' value='22'-->"
+ "<!--#set var='vafe010f2e683908fee32c48d01bb2650' value=''-->"
+ "\n\n<!--#include file='/random_quote'-->"
+ )
+
+ # Do it again, this time from cache.
+ self.assertEqual(
+ self.client.get('/').content.strip(),
+ "<!--#set var='vda0df841702ea993b36d101460264364' value='4'-->"
+ "<!--#set var='va50d914691ecf9b421c680d93ba1263e' value='22'-->"
+ "<!--#set var='vafe010f2e683908fee32c48d01bb2650' value=''-->"
+ "\n\n<!--#include file='/random_quote'-->"
+ )
+ self.assertEqual(
+ self.client.get('/random_quote').content.strip(),
+ "<!--#include "
+ "file='/quote/${vda0df841702ea993b36d101460264364}'-->"
+ )
+
+ @override_settings(SSIFY_DEBUG=True)
+ def test_debug_render_random_quote(self):
+ """Renders the complete view using the DebugSsiMiddleware."""
+ response = self.client.get('/')
+ if hasattr(response, 'render') and callable(response.render):
+ response.render()
+ self.assertEqual(
+ response.content.strip(),
+ """Simple is better than complex.
+Line 4 of 22
+Even number of characters."""
+ )
--- /dev/null
+from django.conf.urls import patterns, url
+from django.views.generic import TemplateView
+
+
+urlpatterns = patterns(
+ 'tests.views',
+
+ url(r'^$',
+ TemplateView.as_view(template_name='tests/main.html')
+ ),
+ url(r'^number_zero$',
+ TemplateView.as_view(template_name='tests/number_zero.html')
+ ),
+ url(r'^random_quote$', 'random_quote', name='random_quote'),
+ url(r'^quote/(?P<number>.+)$', 'quote', name='quote'),
+)
--- /dev/null
+from django.shortcuts import render
+from ssify import ssi_included, ssi_expect, SsiVariable as V
+
+
+@ssi_included(use_lang=False, get_ssi_vars=lambda number: [
+ ('test_tags.number_of_quotes',),
+ ('test_tags.quote_len_odd', (ssi_expect(number, int),))
+])
+def quote(request, number):
+ number = int(number)
+ return render(request, 'tests/quote.html', {
+ 'number': number,
+ 'quote': QUOTES[number]
+ })
+
+
+@ssi_included(use_lang=False, get_ssi_vars=lambda: (
+ lambda number: [number] + quote.get_ssi_vars(number))(
+ number=V('test_tags.random_number', [V('test_tags.number_of_quotes')])
+ ))
+def random_quote(request):
+ """
+ This view is purposely overcomplicated to test interdependencies
+ between SSI variables and SSI includes.
+
+ It finds number of quotes and sets that in an SSI variable,
+ then uses that to set a random quote number in a second variable,
+ then sets a third saying if the length of the selected quote is odd.
+
+ """
+ return render(request, 'tests/random_quote.html')
+
+
+# Nothing interesting here.
+def _quotes():
+ import sys
+ import cStringIO
+ stdout_backup = sys.stdout
+ sys.stdout = cStringIO.StringIO()
+ import this
+ this_string = sys.stdout.getvalue()
+ sys.stdout.close()
+ sys.stdout = stdout_backup
+ return this_string.split('\n')
+
+QUOTES = _quotes()