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

doc/source/topics/settings.rst

@@ -508,6 +508,28 @@ This setting can be used in the case where a separate panel is used for
 managing a custom property or if a certain custom property should never be
 edited.
 
+
+``MESSAGES_PATH``
+-----------------
+
+.. versionadded:: 9.0.0(Mitaka)
+
+Default: ``None``
+
+The absolute path to the directory where message files are collected.
+
+When the user logins to horizon, the message files collected are processed
+and displayed to the user. Each message file should contain a JSON formatted
+data and must have a .json file extension. For example::
+
+    {
+        "level": "info",
+        "message": "message of the day here"
+    }
+
+Possible values for level are: success, info, warning and error.
+
+
 ``OPENSTACK_API_VERSIONS``
 --------------------------
 

horizon/exceptions.py

@@ -217,6 +217,11 @@ class WorkflowValidationError(HorizonException):
     pass
 
 
+class MessageFailure(HorizonException):
+    """Exception raised during message notification."""
+    pass
+
+
 class HandledException(HorizonException):
     """Used internally to track exceptions that have gone through
     :func:`horizon.exceptions.handle` more than once.

horizon/notifications.py

@@ -0,0 +1,150 @@
+# 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)

horizon/test/messages/test_info.json

@@ -0,0 +1 @@
+{"level": "info", "message": "info message"}

horizon/test/messages/test_invalid.json

@@ -0,0 +1 @@
+invalid msg file

horizon/test/messages/test_warning.json

@@ -0,0 +1 @@
+{"level": "warning", "message": "warning message"}

horizon/test/tests/notifications.py

@@ -0,0 +1,59 @@
+# 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 os
+
+from django.conf import settings
+
+from horizon import exceptions
+from horizon.notifications import JSONMessage
+from horizon.test import helpers as test
+
+
+class NotificationTests(test.TestCase):
+
+    MESSAGES_PATH = os.path.abspath(os.path.join(settings.ROOT_PATH,
+                                                 'messages'))
+
+    def _test_msg(self, path, expected_level, expected_msg=''):
+        msg = JSONMessage(path)
+        msg.load()
+
+        self.assertEqual(expected_level, msg.level_name)
+        self.assertEqual(expected_msg, msg.message)
+
+    def test_warning_msg(self):
+        path = self.MESSAGES_PATH + '/test_warning.json'
+
+        self._test_msg(path, 'warning', 'warning message')
+
+    def test_info_msg(self):
+        path = self.MESSAGES_PATH + '/test_info.json'
+
+        self._test_msg(path, 'info', 'info message')
+
+    def test_invalid_msg_file(self):
+        path = self.MESSAGES_PATH + '/test_invalid.json'
+
+        with self.assertRaises(exceptions.MessageFailure):
+            msg = JSONMessage(path)
+            msg.load()
+
+    def test_invalid_msg_file_fail_silently(self):
+        path = self.MESSAGES_PATH + '/test_invalid.json'
+
+        msg = JSONMessage(path, fail_silently=True)
+        msg.load()
+
+        self.assertTrue(msg.failed)

openstack_dashboard/local/local_settings.py.example

@@ -40,6 +40,11 @@ WEBROOT = '/'
 #CSRF_COOKIE_SECURE = True
 #SESSION_COOKIE_SECURE = True
 
+# The absolute path to the directory where message files are collected.
+# The message file must have a .json file extension. When the user logins to
+# horizon, the message files collected are processed and displayed to the user.
+#MESSAGES_PATH=None
+
 # Overrides for OpenStack API versions. Use this setting to force the
 # OpenStack dashboard to use a specific API version for a given service API.
 # Versions specified here should be integers or floats, not strings.

openstack_dashboard/views.py

@@ -12,12 +12,17 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
+from django.conf import settings
 from django import shortcuts
 import django.views.decorators.vary
 
 import horizon
 from horizon import base
 from horizon import exceptions
+from horizon import notifications
+
+
+MESSAGES_PATH = getattr(settings, 'MESSAGES_PATH', None)
 
 
 def get_user_home(user):
@@ -42,4 +47,8 @@ def splash(request):
     response = shortcuts.redirect(horizon.get_user_home(request.user))
     if 'logout_reason' in request.COOKIES:
         response.delete_cookie('logout_reason')
+    # Display Message of the Day message from the message files
+    # located in MESSAGES_PATH
+    if MESSAGES_PATH:
+        notifications.process_message_notification(request, MESSAGES_PATH)
     return response

releasenotes/notes/message-of-the-day-19eb745a147ca56d.yaml

@@ -0,0 +1,9 @@
+---
+features:
+  - >
+   [`blueprint message-of-the-day <https://blueprints.launchpad.net/horizon/+spec/message-of-the-day>`_]
+   Message of the day can now be configured in horizon, this will be displayed
+   to the user whenever they login. To enable the feature set ``MESSAGES_PATH``
+   in the local_settting.py to the directory where message files are located.
+   The message file must have a .json file extension.
+