o2app/bootstrap.py

   1 # Copyright (C) 2021 Wind River Systems, Inc.
   2 #
   3 #  Licensed under the Apache License, Version 2.0 (the "License");
   4 #  you may not use this file except in compliance with the License.
   5 #  You may obtain a copy of the License at
   6 #
   7 #      http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 #  Unless required by applicable law or agreed to in writing, software
  10 #  distributed under the License is distributed on an "AS IS" BASIS,
  11 #  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 #  See the License for the specific language governing permissions and
  13 #  limitations under the License.
  14
  15 from retry import retry
  16 import inspect
  17 from typing import Callable
  18
  19 from o2common.adapter.notifications import AbstractNotifications,\
  20     SmoO2Notifications
  21 from o2common.adapter import redis_eventpublisher
  22 from o2common.service import unit_of_work
  23 from o2common.service import messagebus
  24 from o2common.config import config
  25
  26 from o2app.service import handlers
  27 from o2app.adapter.unit_of_work import SqlAlchemyUnitOfWork
  28
  29 from o2ims.adapter import orm as o2ims_orm
  30 from o2dms.adapter import orm as o2dms_orm
  31
  32 from o2ims.adapter.clients import alarm_dict_client
  33
  34
  35 from o2common.helper import o2logging
  36 logger = o2logging.get_logger(__name__)
  37
  38
  39 @retry(tries=100, delay=2, backoff=1)
  40 def wait_for_db_ready(engine):
  41     # wait for db up
  42     logger.info("Wait for DB ready ...")
  43     engine.connect()
  44     logger.info("DB is ready")
  45
  46
  47 def bootstrap(
  48     start_orm: bool = True,
  49     uow: unit_of_work.AbstractUnitOfWork = SqlAlchemyUnitOfWork(),
  50     notifications: AbstractNotifications = None,
  51     publish: Callable = redis_eventpublisher.publish,
  52 ) -> messagebus.MessageBus:
  53
  54     if notifications is None:
  55         notifications = SmoO2Notifications()
  56
  57     if start_orm:
  58         with uow:
  59             # get default engine if uow is by default
  60             engine = uow.session.get_bind()
  61
  62             wait_for_db_ready(engine)
  63             o2ims_orm.start_o2ims_mappers(engine)
  64             o2dms_orm.start_o2dms_mappers(engine)
  65
  66     dependencies = {"uow": uow, "notifications": notifications,
  67                     "publish": publish}
  68     injected_event_handlers = {
  69         event_type: [
  70             inject_dependencies(handler, dependencies)
  71             for handler in event_handlers
  72         ]
  73         for event_type, event_handlers in handlers.EVENT_HANDLERS.items()
  74     }
  75     injected_command_handlers = {
  76         command_type: inject_dependencies(handler, dependencies)
  77         for command_type, handler in handlers.COMMAND_HANDLERS.items()
  78     }
  79
  80     bus = messagebus.MessageBus(
  81         uow=uow,
  82         event_handlers=injected_event_handlers,
  83         command_handlers=injected_command_handlers,
  84     )
  85     messagebus.MessageBus.set_instance(bus)
  86     return bus
  87
  88
  89 def inject_dependencies(handler, dependencies):
  90     params = inspect.signature(handler).parameters
  91     deps = {
  92         name: dependency
  93         for name, dependency in dependencies.items()
  94         if name in params
  95     }
  96     return lambda message: handler(message, **deps)