py27 Ci tests are often broke by new packages

[Alexey Stupnikov]

It is quite common situation that review process is blocked by failed py27 check which in turn is broken by too new version of specific package. Starting from Kilo release cycle, there is a file in openstack/requirements project called upper-constraints.txt [1]; the contents of that file can be used to pin packages used in CI checks.

[1] https://github.com/openstack/requirements/blob/stable/kilo/upper-constraints.txt

[Alexey Stupnikov (astupnikov)]

I have analyzed unpinned packages inter-dependencies. It is impossible to pin python package’s versions with full compliance to our deb/rpm repo. Here are the reasons:
  * python-barbicanclient 3.0.3 (as in MOS7 repo) requires cliff (>=1.10.0,<1.11.0). But cliff is pinned to 1.7.0 version according to its version in MOS7 repos.
  * python-mistral_2015.1.0 (as in MOS7 repo) requires pecan (>=0.8.0). But pecan is pinned to 0.6.1 version according to its version in MOS7 repos.
  * python-oslo.db_1.7.2 requires alembic>=0.7.2 and stevedore>=1.3.0,<1.4.0. But alembic 0.6.7 and stevedore 1.1.0 are in repos.
  * python-oslo.vmware_0.11.2 requires stevedore<1.4.0,>=1.3.0 and eventlet!=0.17.0,>=0.16.1. But stevedore 1.1.0 and eventlet 0.15.2 are in repos.

So it is impossible to sync 7.0 constraints and MOS7 repo and IMO it is too hard to test updated constraints to pin packages to another versions. Closing this bug as Won’t Fix.