previously valid amazon environment now invalid?

[Aaron Bentley]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 2015-04-29 10:43 AM, roger peppe wrote:
>> Once Trusty EOLs, then I think we would be able to drop
>> functionality that 1.18 itself used only for migration.
>> 
>> For example, if juju 1.18 had automatically created .jenvs from
>> the environments.yaml instead of using environments.yaml
>> directly, then when Trusty EOLed, we could drop that
>> functionality.
> 
> OK, this is interesting. So if we do actually want to get rid of
> this feature, the steps would go something like:
> 
> - implement code in current juju-core so that when the juju command
> needs an environment and the .jenv file doesn't exist, the .jenv
> file is created.
> 
> - release that code as part of Ubuntu 16.04 Juju.
> 
> - for the 21.04 release (when we no longer support 16.04 support), 
> we can remove the fallback feature.
> 
> Is that about right?

Yes, I think so.

> Or is even that not possible, because the automatic .jenv creation
> is a feature in itself that must be maintained?

As long as nothing that comes out of $SERIES-updates contains a change
that stops things from working that previously worked, I would be
content.  IOW, I think migrations are a special case.

> Out of interest, how does this apply to command-line flag
> compatibility, where there's no possible automatic migration?

There's no wiggle room.  As William said, "if you're removing or
changing an API, or removing or changing the meaning of a command line
flag, you are Doing It Wrong."

Aaron
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1

iQEcBAEBAgAGBQJVQQJnAAoJEK84cMOcf+9hI/0IALneo7jxfiPzy7Sw5xvDlIiV
yFJ/MMoYvuSPzniC8WCOeBabCw8tdLOR2CFmyv8llmNk9XsmBtB73OH8cztRho5V
v7cAw2slAaZhBxynARvXls7r/+jaI5BI/6cccojYYYoslMroRwFG/YZT1pVwHCgt
eZOXSQ1xRX+6ZkkcFL7D8deLeaGAtgesV8gOP7kw1hqPGGXdJCQgMkJ+vxMt5XH9
93QGU0onP3u7rs/Yy6wvSPafsO3e0yu7oRAQ23yJjfFT0CgbA0APN6qi4i2orfhu
RbS6sYZmRaOca0W8dvRsKkcGgNTwJ0VUxbTrfcOWtt2u46MHnPF9Di+IioQFxIk=
=oYGu
-----END PGP SIGNATURE-----