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Guideline On Refreshing Configuration Files Under etc/
======================================================

During a release cycle many configuration options are changed or updated. The
sample configuration files provided in tree (under ``etc/*``) need to be
updated using the autogeneration tool as these files are being used in
different places. Some examples are devstack gates, downstream packagers
shipping with the same (or using defaults from these files), etc. Hence, before
we cut a release we need to refresh the configuration files shipped with tree
to match the changes done in the source code during the release cycle.

In an ideal world, every review that proposes an addition, removal or update to
a configuration option(s) should use the tox tool to refresh only the
configuration options(s) that were changed. However, many of the configuration
options like those coming from oslo.messaging, oslo_middleware, etc. may have
changed in the meantime. So, whenever someone uses the tool to autogenerate the
configuration files based on the options in tree, there are more changes than
those made just by the author.

We do not recommend the authors to manually edit the autogenerated files so, a
reasonable tradeoff is for the authors to include **only those files** that are
affected by their change(s).


    $ tox -e genconfig


When To Refresh The Sample Configuration Files
==============================================

* Every review that proposes an addition, removal or update to a configuration
  option(s) should use the tox tool to refresh only the configuration option(s)
  they have changed.
* Ideally reviewers should request updates to sample configuration files for
  every change that attempts to add/delete/modify a configuration option(s) in
  the code.
* In some situations however, there may be a bunch of similar changes that are
  affecting the configuration files. In this case, in order to make the
  developers' and reviewers' effort easier, we recommend an update to the
  configuration files in bulk right after all the update changes have been
  made/merged.


**IMPORTANT NOTE**: All sample configuration files mush be updated before the
milestone-3 (or the final release) of the project.

Add guideline to refresh config files shipped with source
Add guideline to refresh config files shipped with source

This commit adds documentation to help authors identify the steps they
need to take while updating the config files and thereafter.

This documentation is being added as per question asked on change
I534a0dc2d9f82ab70517cde12bfd40d4f5ae69e2

There is some discussion as to when we will be getting rid of the config
file from the tree on the change
Iee695870aefc9cb6142dbc7400672b335588fcc9

Until we do get rid of the config files from source, we need to document
this process for any further updates to configs.

Change-Id: I2e3d43e43e00cd2a13b5a0fb794ac6e6d2e24dc2
