lpreports doesn't get new primary on mongo replicaset rebuild

[Igor Shishkin]

Hi,

I've the following issue with LP-reports:

When mongodb in replicaset elects new primary lpreports doesn't catch it up until restart which causes app failure:

Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/flask/app.py", line 1836, in __call__
    return self.wsgi_app(environ, start_response)
  File "/usr/lib/python2.7/dist-packages/flask/app.py", line 1820, in wsgi_app
    response = self.make_response(self.handle_exception(e))
  File "/usr/lib/python2.7/dist-packages/flask_restful/__init__.py", line 270, in error_router
    return original_handler(e)
  File "/usr/lib/python2.7/dist-packages/flask/app.py", line 1403, in handle_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/lib/python2.7/dist-packages/flask/app.py", line 1817, in wsgi_app
    response = self.full_dispatch_request()
  File "/usr/lib/python2.7/dist-packages/flask/app.py", line 1477, in full_dispatch_request
    rv = self.handle_user_exception(e)
  File "/usr/lib/python2.7/dist-packages/flask_restful/__init__.py", line 270, in error_router
    return original_handler(e)
  File "/usr/lib/python2.7/dist-packages/flask/app.py", line 1381, in handle_user_exception
    reraise(exc_type, exc_value, tb)
  File "/usr/lib/python2.7/dist-packages/flask/app.py", line 1475, in full_dispatch_request
    rv = self.dispatch_request()
  File "/usr/lib/python2.7/dist-packages/flask/app.py", line 1461, in dispatch_request
    return self.view_functions[rule.endpoint](**req.view_args)
  File "/usr/lib/python2.7/dist-packages/lpreports/auth.py", line 108, in authorized
    db.add_user(user, update=update)
  File "/usr/lib/python2.7/dist-packages/lpreports/db.py", line 87, in add_user
    store.update({"_id": user["_id"]}, user)
  File "/usr/lib/python2.7/dist-packages/pymongo/collection.py", line 2230, in update
    with self._socket_for_writes() as sock_info:
  File "/usr/lib/python2.7/contextlib.py", line 17, in __enter__
    return self.gen.next()
  File "/usr/lib/python2.7/dist-packages/pymongo/mongo_client.py", line 712, in _get_socket
    server = self._get_topology().select_server(selector)
  File "/usr/lib/python2.7/dist-packages/pymongo/topology.py", line 141, in select_server
    address))
  File "/usr/lib/python2.7/dist-packages/pymongo/topology.py", line 117, in select_servers
    self._error_message(selector))
pymongo.errors.ServerSelectionTimeoutError: No primary available for writes

[Alexander Charykov (acharykov)]

We don't support mongodb replica set. We'll look this at this when when we would have time to make application able to run on several nodes and support multiple connections to mongodb.

[Igor Shishkin (teran)]

Unfortunately you can't say you don't support it since you that concept we had just from the start of migration process and it's discussed design for production run.

[Fuel Devops McRobotson (fuel-devops-robot)]

Related fix proposed to branch: master
Change author: Igor Shishkin <email address hidden>
Review: https://review.fuel-infra.org/21260

[Fuel Devops McRobotson (fuel-devops-robot)]

Reviewed: https://review.fuel-infra.org/21260
Submitter: Igor Shishkin <email address hidden>
Branch: master

Commit: c6ca495f34a1d695c35e9db36a7d44053e7df690
Author: Igor Shishkin <email address hidden>
Date: Thu May 26 08:33:21 2016

Fix for lpreports issue with refreshing mongo rs state on uwsgi side

Change-Id: I84b613d1cf6b755e73cdb4e314c5092e5732bd43
Related-Bug: #1585559
Signed-off-by: Igor Shishkin <email address hidden>