deb-horizon/horizon/notifications.py
lin-hua-cheng 0e025d9d71 Add message of the day option
Allow user to configure messages to display to the user
after they login.

Change-Id: I6dc0318708d0f964e52c8b127718297fc723651c
Implements: blueprint message-of-the-day
2016-01-22 11:31:36 -08:00

151 lines
4.2 KiB
Python

# Copyright (C) 2015 Yahoo! Inc. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License"); you may
# not use this file except in compliance with the License. You may obtain
# a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
# WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
# License for the specific language governing permissions and limitations
# under the License.
import glob
import json
import logging
import os
from django.utils.safestring import mark_safe
from django.utils.translation import ugettext_lazy as _
from horizon import exceptions
from horizon import messages
LOG = logging.getLogger(__name__)
_MESSAGES_CACHE = None
_MESSAGES_MTIME = None
class JSONMessage(object):
INFO = messages.info
SUCCESS = messages.success
WARNING = messages.warning
ERROR = messages.error
MESSAGE_LEVELS = {
'info': INFO,
'success': SUCCESS,
'warning': WARNING,
'error': ERROR
}
def __init__(self, path, fail_silently=False):
self._path = path
self._data = ''
self.failed = False
self.fail_silently = fail_silently
self.message = ''
self.level = self.INFO
self.level_name = 'info'
def _read(self):
with open(self._path, 'rb') as file_obj:
self._data = file_obj.read()
def _parse(self):
attrs = {}
try:
data = self._data.decode('utf-8')
attrs = json.loads(data)
except ValueError as exc:
self.failed = True
msg = _("Message json file '%(path)s' is malformed."
" %(exception)s")
msg = msg % {'path': self._path, 'exception': str(exc)}
if self.fail_silently:
LOG.warning(msg)
else:
raise exceptions.MessageFailure(msg)
else:
level_name = attrs.get('level', 'info')
if level_name in self.MESSAGE_LEVELS:
self.level_name = level_name
self.level = self.MESSAGE_LEVELS.get(self.level_name, self.INFO)
self.message = attrs.get('message', '')
def load(self):
"""Read and parse the message file."""
try:
self._read()
self._parse()
except Exception as exc:
self.failed = True
msg = _("Error processing message json file '%(path)s': "
"%(exception)s")
msg = msg % {'path': self._path, 'exception': str(exc)}
if self.fail_silently:
LOG.warning(msg)
else:
raise exceptions.MessageFailure(msg)
def send_message(self, request):
if self.failed:
return
self.level(request, mark_safe(self.message))
def _is_path(path):
if os.path.exists(path) and os.path.isdir(path):
return True
else:
return False
def _get_processed_messages(messages_path):
msgs = list()
if not _is_path(messages_path):
LOG.error('%s is not a valid messages path.', messages_path)
return msgs
# Get all files from messages_path with .json extension
for fname in glob.glob(os.path.join(messages_path, '*.json')):
fpath = os.path.join(messages_path, fname)
msg = JSONMessage(fpath, fail_silently=True)
msg.load()
if not msg.failed:
msgs.append(msg)
return msgs
def process_message_notification(request, messages_path):
"""Process all the msg file found in the message directory"""
if not messages_path:
return
global _MESSAGES_CACHE
global _MESSAGES_MTIME
# NOTE (lhcheng): Cache the processed messages to avoid parsing
# the files every time. Check directory modification time if
# reload is necessary.
if (_MESSAGES_CACHE is None
or _MESSAGES_MTIME != os.path.getmtime(messages_path)):
_MESSAGES_CACHE = _get_processed_messages(messages_path)
_MESSAGES_MTIME = os.path.getmtime(messages_path)
for msg in _MESSAGES_CACHE:
msg.send_message(request)