Re: [atomic] "LABEL install/uninstall" guidelines

[Ken Dreyer <kdreyer redhat com>]

Thanks Micah for the pointers, that is really helpful.

- Ken

On Tue, Feb 7, 2017 at 8:07 AM, Micah Abbott <miabbott redhat com> wrote:
> On 02/06/2017 06:47 PM, Ken Dreyer wrote:
>>
>> Are there any guidelines or policies for what to put in the "install"
>> or "uninstall" labels in my Dockerfiles? Can images basically do
>> whatever they want in those scripts?
>
>
> I don't believe there are any guidelines for what can or cannot be used in
> those labels.
>
>> I see examples where the install script sets up systemd unit files -
>> is that the pattern these install shell scripts should always follow?
>
>
> If the application requires a systemd unit file, that's what should be
> installed.  However, this is not required.
>
> For example, the Cockpit container has an INSTALL label that runs a script
> to land a few files on the host and runs
>
> https://github.com/cockpit-project/cockpit-container/blob/master/Dockerfile#L16
>
> https://github.com/cockpit-project/cockpit-container/blob/master/atomic-install
>
>> I also saw an example where an image provides "LABEL install" but no
>> "LABEL uninstall". Is that bad?
>
>
> Again, there aren't any strict rules about what labels to provide.  I think
> a reasonable expectation is that if you are installing something, you should
> also have a way to uninstall it.
>
>
> Related to this topic of labels, there is an upstream effort to come up with
> a set of default names for labels:
>
> https://github.com/projectatomic/ContainerApplicationGenericLabels