X-Git-Url: https://git.mdrn.pl/wolnelektury.git/blobdiff_plain/ae60b2a3949e96357477cc04f90fd0873cee8a92..05cca019b7dba62e457feb47df10e7a41dd939ef:/src/wolnelektury/utils.py diff --git a/src/wolnelektury/utils.py b/src/wolnelektury/utils.py index e8aa7fb27..b0b972657 100644 --- a/src/wolnelektury/utils.py +++ b/src/wolnelektury/utils.py @@ -1,11 +1,27 @@ -# -*- 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. # +import codecs +import csv +from functools import wraps +from inspect import getargspec +from io import BytesIO +import json import os import pytz +import re + +from django.conf import settings +from django.core.cache import cache +from django.core.mail import send_mail +from django.http import HttpResponse +from django.template.loader import render_to_string from django.utils import timezone +from django.utils.translation import get_language from django.conf import settings +from django.utils.safestring import mark_safe +from django.utils.translation import ugettext + tz = pytz.timezone(settings.TIME_ZONE) @@ -23,3 +39,171 @@ def utc_for_js(dt): def makedirs(path): if not os.path.isdir(path): os.makedirs(path) + + +def stringify_keys(dictionary): + return dict((keyword.encode('ascii'), value) + for keyword, value in dictionary.items()) + + +def json_encode(obj, sort_keys=True, ensure_ascii=False): + return json.dumps(obj, sort_keys=sort_keys, ensure_ascii=ensure_ascii) + + +def json_decode(obj): + return json.loads(obj) + + +def json_decode_fallback(value): + try: + return json_decode(value) + except ValueError: + return value + + +class AjaxError(Exception): + pass + + +def ajax(login_required=False, method=None, template=None, permission_required=None): + def decorator(fun): + @wraps(fun) + def ajax_view(request): + kwargs = {} + request_params = None + if method == 'post': + request_params = request.POST + elif method == 'get': + request_params = request.GET + fun_params, xx, fun_kwargs, defaults = getargspec(fun) + if defaults: + required_params = fun_params[1:-len(defaults)] + else: + required_params = fun_params[1:] + missing_params = set(required_params) - set(request_params) + if missing_params: + res = { + 'result': 'missing params', + 'missing': ', '.join(missing_params), + } + else: + if request_params: + request_params = dict( + (key, json_decode_fallback(value)) + for key, value in request_params.items() + if fun_kwargs or key in fun_params) + kwargs.update(stringify_keys(request_params)) + res = None + if login_required and not request.user.is_authenticated: + res = {'result': 'logout'} + if (permission_required and + not request.user.has_perm(permission_required)): + res = {'result': 'access denied'} + if not res: + try: + res = fun(request, **kwargs) + if res and template: + res = {'html': render_to_string(template, res, request=request)} + except AjaxError as e: + res = {'result': e.args[0]} + if 'result' not in res: + res['result'] = 'ok' + return HttpResponse(json_encode(res), content_type='application/json; charset=utf-8', + status=200 if res['result'] == 'ok' else 400) + + return ajax_view + + return decorator + + +def send_noreply_mail(subject, message, recipient_list, **kwargs): + send_mail( + '[WolneLektury] ' + subject, + message + "\n\n-- \n" + ugettext('Message sent automatically. Please do not reply.'), + 'no-reply@wolnelektury.pl', recipient_list, **kwargs) + + +# source: https://docs.python.org/2/library/csv.html#examples +class UnicodeCSVWriter(object): + """ + A CSV writer which will write rows to CSV file "f", + which is encoded in the given encoding. + """ + + def __init__(self, f, dialect=csv.excel, encoding="utf-8", **kwds): + # Redirect output to a queue + self.queue = BytesIO() + self.writer = csv.writer(self.queue, dialect=dialect, **kwds) + self.stream = f + self.encoder = codecs.getincrementalencoder(encoding)() + + def writerow(self, row): + self.writer.writerow([s.encode("utf-8") for s in row]) + # Fetch UTF-8 output from the queue ... + data = self.queue.getvalue() + data = data.decode("utf-8") + # ... and reencode it into the target encoding + data = self.encoder.encode(data) + # write to the target stream + self.stream.write(data) + # empty queue + self.queue.truncate(0) + + def writerows(self, rows): + for row in rows: + self.writerow(row) + + +# the original re.escape messes with unicode +def re_escape(s): + return re.sub(r"[(){}\[\].*?|^$\\+-]", r"\\\g<0>", s) + + +BOT_BITS = ['bot', 'slurp', 'spider', 'facebook', 'crawler', 'parser', 'http'] + + +def is_crawler(request): + user_agent = request.META.get('HTTP_USER_AGENT') + if not user_agent: + return True + user_agent = user_agent.lower() + return any(bot_bit in user_agent for bot_bit in BOT_BITS) + + +def get_cached_render_key(instance, property_name, language=None): + if language is None: + language = get_language() + return 'cached_render:%s.%s:%s:%s' % ( + type(instance).__name__, + property_name, + instance.pk, + language + ) + + +def cached_render(template_name, timeout=24 * 60 * 60): + def decorator(method): + @wraps(method) + def wrapper(self): + key = get_cached_render_key(self, method.__name__) + content = cache.get(key) + if content is None: + context = method(self) + content = render_to_string(template_name, context) + cache.set(key, str(content), timeout=timeout) + else: + content = mark_safe(content) + return content + return wrapper + return decorator + + +def clear_cached_renders(bound_method): + for lc, ln in settings.LANGUAGES: + cache.delete( + get_cached_render_key( + bound_method.__self__, + bound_method.__name__, + lc + ) + )