Feature-request: bosh releases should be able to perform post-install actions on the CLI machine

[evanfarrar]

BUCC is really cool. It has one thing in particular that is a super power I'd like to give to all things BOSH: after you install Concourse, you are configured to use Concourse.

Here's what it is normally like:

1. run this command to install concourse
2. now interrogate credhub to figure out what secrets/infrastructure were generated
3. use the results of that interrogation to log in to concourse and fly set-pipeline

What if it were like this:

1. run this command to install concourse:bosh deploy -d concourse -v target-name=myconcourse
2. fly -t myconcourse set-pipeline --pipeline my-pipeline --config pipeline.yml
3. There is no step three.

This same concept applies to CFAR and the CF cli, and to CFCR and the kubectl cli. This would be something to run locally after the whole release is resolved, possibly after the whole manifest has successfully deployed.

Risks/Challenges/Thoughts:

• well, for starters, this is probably somewhat operating system specific. The process by which I target concourse on Windows is probably different than on Linux.
• This is so convenient that I will want to re-enter it, so I may want to run just the local-post-deploy hooks in a release.
• This almost necessarily involves secrets, and a lot of baggage comes along with that: what if I don't want this written to disk? What if it is rotated while I'm trying to use it?
• In addition to implicit targeting One MVP iteration of this would be to simply output to screen the whole host of variables you need to log into your concourse:

Thanks for installing concourse! Run this to log into your concourse:
fly -t myconcourse --api https://54.172.12.7 --password qwertyuiop --user admin