Hi CF,

CAPI would like to introduce a validation where we disallow environment
variables that begin with “CF_”. For context, we already [1] have several
validations for environment variables, e.g. “VCAP_”. We would like to
prohibit “CF_” for a couple reasons:

1. There are several environment variables with the prefix “CF_” that
are already set in containers running on the platform. Currently, without
this validation, users can override these with app environment variables.
2. VCAP_APPLICATION doesn’t quite fit for the V3 API world where apps
can be made up of multiple processes and tasks. See [2] original discussion
and [3] proposed environment variables we will introduce as we roll out the
V3 API.


If this is acceptable, we’d like to propose adding this validation in an
upcoming version of Cloud Foundry. The plan might look something like this:

1. Announce that the validation would be added in a certain version of
Cloud Foundry.
2. Complete the [3] story for the new “CF_” environment variables.
3. Announce the version where we will remove VCAP_APPLICATION, say
completion of above story + 5 versions.



Please let us know if you have any feedback for the validation itself or
the plan to roll this out.

Thanks!

Nick


[1]
https://github.com/cloudfoundry/cloud_controller_ng/blob/master/app/messages/validators.rb#L41-L47
[2]
https://lists.cloudfoundry.org/archives/list/cf-dev(a)lists.cloudfoundry.org/thread/LTF4NAKWF56SEER57ZNBO5SLM72NPTQJ/#LTF4NAKWF56SEER57ZNBO5SLM72NPTQJ
[3] https://www.pivotaltracker.com/story/show/126180869

--
Nicholas Calugar
Product Manager - Cloud Foundry API
Pivotal Software, Inc.