[katello-devel] Modelling of environments, products, etc in Katello (related to renaming of environments)

[jesus m. rodriguez]

On 08/09/2012 08:39 AM, Dmitri Dolguikh wrote:
> On 09/08/12 01:20 PM, James Bowes wrote:
>> On Thu, Aug 09, 2012 at 12:34:57PM +0100, Dmitri Dolguikh wrote:
>>> Please see https://bugzilla.redhat.com/show_bug.cgi?id=795928 for
>>> description of an issue with environment renaming.
>>>
>>> The immediate problems around environments: using of environment
>>> names and environment ids for identification of environments
>>> interchangeably. Using db ids for environment identification when
>>> not using environment names.
>>>
>>> To resolve these:
>>>    - introduce environment uuids
>>>    - update katello/katello cli to use uuids for environment identification
>>>    - update repository naming to use environment uuids
>>>    - update candlepin (this will include updates to schema, and
>>> resource controller)
>>>
>> -1 to UUIDs, for the same reason as has been discussed wrt pulp
>> repo labels. a url like:
>>
>> https://my-cdn.local/content/dev/rhel-server/i386/
>>
>> is way more useful than:
>>
>> https://my-cdn.local/content/abc123213-23423423-aaa123/rhel-server/i386/
>>
>> not to mention, far more handsome!
>>
>> I'd rather see either immutable labels, or supporting renaming labels,
>> too.
> The issue boils down to renaming of environments. If we are to use
> environment names for environment identification, we have to provide
> resolution for urls that are no longer valid (via 301). Doable, but
> additional work.

Labels are not necessarily environment names. Nothing says you have to 
allow changing of the label. The label is just a human readable identifier 
that is both easy to remember and use.

While allowing renaming of labels is nice, I don't think it is necessary. 
Even if you allow renaming the environment (the one shown on the page).

Think of the trac wiki url. If I create a new page I can call it 
DesignLabelsEnvironments. But change the title on the page to be 'Design of 
Labels for Environments'. Later I change the title to be: 'Environment 
Label Design'. I don't have to change the page name. If I want to I just 
create a new one. So if you want to allow label renaming, then make it easy 
to create Environments.


> The idea of labels is interesting, but I don't think it would work out
> in the long-term: it would become stale after a rename or two

The labels is what we used for RHN Satellite for Channels. It works and a 
lot easier to remember. I can guarantee if you go with UUID you *WILL* get 
someone asking why can't they pass in a name. And using the actual name is 
bad because they will have spaces and might have to be translated. Labels 
are again human readable.

>
> With uuid's we won't need to support url redirection, they won't go
> stale. For user-friendliness we should provide querying by name with
> environment resource, smt. like:

Nothing says you have to offer redirection with labels. If you make them 
static and force users to create a new environment to get a new label.

So let's walk through the label rename then. You let a user change the 
label of an environment. So now instead of being 'int-dev' it becomes 
'devel'. You could simply return 404 for anyone still using 'int-dev' just 
like they were if they used the wrong uuid.

If you *MUST* offer 301 'moved permanently' for the label then you'll have 
to keep a list of labels. But I think that's going to be more of a user 
issue. Because I know people will want to reuse label names later. So I 
think most of them will be ok if you have a 404 for a non existent label.

IMO I don't think you need to offer label renames. Just allow renaming of 
the environment for displaying on the UI. That way your urls are easier to 
use, cli will be easier to use, and you'll get less complaints.

>
> GET
> http://localhost/katello/api/organizations/ACME_Corporation/environments?name=super-duper
>
> Less convenient, but easier to implement and maintain (from both user
> and developer perspective).

I don't understand what your example is about. name should never be used, 
it should be label:

../ACME_Corporation/environments?label=super-duper

jesus

-- 
jesus m. rodriguez          | jesusr at redhat.com
principal software engineer | irc: zeus
red hat systems management  | 919.754.4413 (w)
rhce # 805008586930012      | 919.623.0080 (c)
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