External repos in charms - Please consider before relying on them

[Clint Byrum]

Excerpts from Clint Byrum's message of 2012-08-15 11:35:55 -0700:
> Hey everybody. I've noticed a lot of wgets and git clones in charms and
> it concerns me a bit.
> 
> The idea behind juju is to make it simpler to get on the cloud and to
> help people get into a "scale out" mind set. In order to do that, we
> need things like 'add-unit' to be reliable.
> 
> This means considering how reliable those external services are. So I
> have proposed this change to charm store policy:
> 
> https://code.launchpad.net/~clint-fewbar/juju/docs-external-repos/+merge/119761

Oops, wrong target. Here is the correct MP

https://code.launchpad.net/~clint-fewbar/juju/docs-external-repos/+merge/119786

> 
> Its really just making an explicit admonition to maintainers to consider
> how reliable any external services are in official charms.
> 
> Long term I think we'll be able to guarantee reliability of 'add-unit'
> by caching downloads and/or booting from snapshotted containers/images.
> But that is a long way off, so this policy should help to make sure we
> don't get users into a bad situation where they can't scale out when
> they need to.