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

[James Bowes]

On Thu, Aug 09, 2012 at 01:39:56PM +0100, 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 resolution for urls that are no longer valid (via 301).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.
> 

label and name can be seperate. label could be my-env, name could be "My
Environment". label is something that can be easily passed into a cli
command, or put in a yum url for content downloads. name would just be
something you view.

I don't think it's necessary to support redirection.

> 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
>

Unless you update the label at the same time.

> 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:
> 
> GET http://localhost/katello/api/organizations/ACME_Corporation/environments?name=super-duper
> 

That's effectively the same as using the label directly in the path of
the url, isn't it?

> Less convenient, but easier to implement and maintain (from both
> user and developer perspective).
> 
> -d
> 
> >
> >To clarify, UUIDs are fine imo as an internal canonical id for envs
> >within katello as a whole, but once the env is exposed on the cli or in
> >a url, label should be used.
> >
> >>The larger problem: Katello and Candlepin modelling of
> >>products/product content/environments lost coherency.
> >>
> >>Candlepin's view of the above trifecta (use of a monospaced font is
> >>encouraged for the content below):
> >>+-------------+          +--------------------+
> >>| Environment | 1 <--- * | EnvironmentContent |
> >>+-------------+          +--------------------+
> >>                                 ^
> >>                                 | *
> >>                                 | 1
> >>+---------+          +----------------+
> >>     | Product | 1 ---> * | ProductContent |
> >>     +---------+          +----------------+
> >>
> >>
> >>same thing in Katello (with added pulp repositories):
> >>
> >>    +-------------+
> >>    | Pulp::Repos |<-----------------------+
> >>    +-------------+                        |
> >>        ^                                  |
> >>        | uses                             |
> >>     +----------------------------------+  |  +-------------+
> >>     | Candlepin::Product               |  |  | Environment |
> >>     | (uses Candlepin::ProductContent) |  |  +-------------+
> >>     +----------------------------------+  |          ^
> >>        |       ^                          |          | 1
> >>        |uses   | uses                     |          |
> >>        |       |                          |          | *
> >>+---------+                      +--------------------+
> >>       | Product | 1 ---------------> * | EnvironmentProduct |
> >>       +---------+                      +--------------------+
> >>                                           |          |1
> >>                                           |          |*
> >>                                           |          V
> >>                                           | uses +------------+
> >>                                           +------| Repository |
> >>                                                  +------------+
> >>
> >>
> >>I propose:
> >>  - Rename EnvironmentProduct to ProductContent
> >>    - make it use Candlepin::ProductContent
> >>    - remove use of Pulp::Repos from Product
> >>    - delegate responsibility of generation of environment uuids to
> >>Candlepin (should cp folks agree on this)
> >>
> >>resulting in:
> >>
> >>                         +-------------+
> >>                         | Environment |
> >>                         +-------------+
> >>                                ^
> >>                                | 1
> >>                                | *
> >>   +---------+          +----------------+
> >>   | Product | 1 ---> * | ProductContent |
> >>   +---------+          +----------------+
> >>                            |1  | uses
> >>                            |   |    +---------------------------+
> >>                            |1  +->  | Candlepin::ProductContent |
> >>                            V        +---------------------------+
> >>     +-------------+ uses +------------+
> >>     | Pulp::Repos |<-----| Repository |
> >>     +-------------+      +------------+
> >>
> >>I don't think many-1 relation is required on
> >>Repository-ProductContent, it's 1-1?
> >>
> >>
> >>Thoughts, concerns, opinions?
> >>-d
> >>
> >>
> >>
> >>
> >>_______________________________________________
> >>katello-devel mailing list
> >>katello-devel at redhat.com
> >>https://www.redhat.com/mailman/listinfo/katello-devel
> >
> >-James
> 
> 

-James
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