[fuel-devops 3.0] AddressPool._safe_create_network does not protect from race condition

[Anton Studenov]

When multiple environments are being created at the same time, there is a race condition
for AddressPool networks.

Steps to reproduce:
  Run two dos.py create-env simultaneously

Expected result:
  Environments are created properly

Actual result:
  Second environment gets error stacktrace:

File "/home/tohin/.virtualenvs/devops3.0.0/bin/dos.py", line 6, in <module>
    exec(compile(open(__file__).read(), __file__, 'exec'))
  File "/home/tohin/Code/fuel-devops/bin/dos.py", line 22, in <module>
    main()
  File "/home/tohin/Code/fuel-devops/devops/shell.py", line 628, in main
    Shell(args).execute()
  File "/home/tohin/Code/fuel-devops/devops/shell.py", line 55, in execute
    self.commands.get(self.params.command)(self)
  File "/home/tohin/Code/fuel-devops/devops/shell.py", line 219, in do_create_env
    self._create_env_from_config(config)
  File "/home/tohin/Code/fuel-devops/devops/shell.py", line 228, in _create_env_from_config
    self.env = Environment.create_environment(config)
  File "/home/tohin/Code/fuel-devops/devops/models/environment.py", line 314, in create_environment
    environment.add_address_pools(address_pools)
  File "/home/tohin/Code/fuel-devops/devops/models/environment.py", line 121, in add_address_pools
    **data.get('params', {})
  File "/home/tohin/Code/fuel-devops/devops/models/environment.py", line 138, in add_address_pool
    **params
  File "/home/tohin/Code/fuel-devops/devops/models/network.py", line 248, in address_pool_create
    **params
  File "/home/tohin/.virtualenvs/devops3.0.0/local/lib/python2.7/site-packages/Django-1.8.13-py2.7.egg/django/utils/decorators.py", line 145, in inner
    return func(*args, **kwargs)
  File "/home/tohin/Code/fuel-devops/devops/models/network.py", line 230, in _safe_create_network
    transaction.rollback()
  File "/home/tohin/.virtualenvs/devops3.0.0/local/lib/python2.7/site-packages/Django-1.8.13-py2.7.egg/django/db/transaction.py", line 49, in rollback
    get_connection(using).rollback()
  File "/home/tohin/.virtualenvs/devops3.0.0/local/lib/python2.7/site-packages/Django-1.8.13-py2.7.egg/django/db/backends/base/base.py", line 182, in rollback
    self.validate_no_atomic_block()
  File "/home/tohin/.virtualenvs/devops3.0.0/local/lib/python2.7/site-packages/Django-1.8.13-py2.7.egg/django/db/backends/base/base.py", line 322, in validate_no_atomic_block
    "This is forbidden when an 'atomic' block is active.")
django.db.transaction.TransactionManagementError: This is forbidden when an 'atomic' block is active.

Workaround:
  Create environments consecutively

Impact:
  May affect CI

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/336566

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/336566
Committed: https://git.openstack.org/cgit/openstack/fuel-devops/commit/?id=59742856f8071a3482d013910db7fb1ecfc6bda3
Submitter: Jenkins
Branch: master

commit 59742856f8071a3482d013910db7fb1ecfc6bda3
Author: Anton Studenov <email address hidden>
Date: Fri Jul 1 16:42:36 2016 +0300

    Fix AddressPool._safe_create_network

    - transaction.atomic was used improperly.
      transaction.rollback() will be called at atomic.__exit__
      in case of error
    - Added DevopsError for duplicate names and networks
    - Added unit tests

    Closes-Bug: #1598141
    Closes-Bug: #1597025
    Change-Id: I024c29761048447446a09ac4439cca66e60b11d4

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: release/2.9
Review: https://review.openstack.org/350400

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/350400
Committed: https://git.openstack.org/cgit/openstack/fuel-devops/commit/?id=fa073f615de9d247960b97f725d5cc543e480aaa
Submitter: Jenkins
Branch: release/2.9

commit fa073f615de9d247960b97f725d5cc543e480aaa
Author: Alexey Stepanov <email address hidden>
Date: Wed Aug 3 10:05:58 2016 +0300

    Fix AddressPool._safe_create_network

    - transaction.atomic was used improperly.
      transaction.rollback() will be called at atomic.__exit__
      in case of error
    - Added DevopsError for duplicate names and networks
    - Added unit tests

    Closes-Bug: #1598141
    Closes-Bug: #1597025
    Closes-bug: #1607342
    Change-Id: I024c29761048447446a09ac4439cca66e60b11d4