[Freeipa-devel] [PATCH] 1106 IPA REST smart proxy

[Dmitri Pal]

On 02/18/2014 04:01 AM, Petr Viktorin wrote:
> On 02/18/2014 07:52 AM, Martin Kosek wrote:
>> On 02/18/2014 12:11 AM, Dmitri Pal wrote:
>>> On 02/17/2014 04:57 PM, Rob Crittenden wrote:
>>>> Dmitri Pal wrote:
>>>>> On 02/17/2014 04:13 PM, Rob Crittenden wrote:
>>>>>> Dmitri Pal wrote:
>>>>>>> On 02/17/2014 02:33 PM, Rob Crittenden wrote:
>>>>>>>> Dmitri Pal wrote:
>>>>>>>>> On 02/17/2014 01:21 PM, Rob Crittenden wrote:
>>>>>>>>>> Martin Kosek wrote:
>>>>>>>>>>> On 02/14/2014 11:26 PM, Dmitri Pal wrote:
>>>>>>>>>>> +1, this was exactly my goal. It is easy to name and organize
>>>>>>>>>>> things
>>>>>>>>>>> now,
>>>>>>>>>>> difficult to do when it is live upstream and/or integrated with
>>>>>>>>>>> Foreman.
>>>>>>>>>>>
>>>>>>>>>>> I think the key for the right naming is a fact if this is 
>>>>>>>>>>> really
>>>>>>>>>>> specific to
>>>>>>>>>>> Foreman or it is a truly general design usable also in other 
>>>>>>>>>>> use
>>>>>>>>>>> cases. If
>>>>>>>>>>> Foreman-specific, I would go with
>>>>>>>>>>> freeipa-server-smartproxy-host or
>>>>>>>>>>> similar.
>>>>>>>>>>>
>>>>>>>>>>> If general, we can go with
>>>>>>>>>>>
>>>>>>>>>>> freeipa-server-proxy-host
>>>>>>>>>>> freeipa-server-proxy-user
>>>>>>>>>>> freeipa-server-proxy-dhcp
>>>>>>>>>>>
>>>>>>>>>>> The proxies may share the framework and only expose the 
>>>>>>>>>>> requested
>>>>>>>>>>> part of the
>>>>>>>>>>> tree - which in advance gives you an option for an API
>>>>>>>>>>> separation, as
>>>>>>>>>>> compared
>>>>>>>>>>> to general freeipa-server-smartproxy.
>>>>>>>>>>
>>>>>>>>>> I still don't get the point of this. Are you proposing having 3
>>>>>>>>>> different servers, each providing a unique service? Or one 
>>>>>>>>>> service
>>>>>>>>>> that one can turn on/off features, or something else? Do you
>>>>>>>>>> envision
>>>>>>>>>> this as 3 separate subpackages?
>>>>>>>>>>
>>>>>>>>>> There is no "framework" in my current patch, it is a cherrypy
>>>>>>>>>> server
>>>>>>>>>> that exposes parts of IPA on a given URI. It is the thinnest of
>>>>>>>>>> layers.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Then it seems to make sense to have 3 different packages that
>>>>>>>>> can be
>>>>>>>>> optionally coninstalled and would probably share the same
>>>>>>>>> principal,
>>>>>>>>> keytab and local REST API socket/port.
>>>>>>>>>
>>>>>>>>
>>>>>>>> Well, what you are designing is a central framework with plugins.
>>>>>>>> What
>>>>>>>> I designed is a quick-and-dirty get something up quickly. We 
>>>>>>>> need to
>>>>>>>> pick one. The plugable method is going to require a fair bit of
>>>>>>>> rework, though it will potentially pay dividends in the future.
>>>>>>>
>>>>>>> I think that we can start where you are but drive towards this
>>>>>>> architecture via refactoring. But we need to pick the right name 
>>>>>>> now.
>>>>>>> Even if the architecture is not there yet we should name the
>>>>>>> package in
>>>>>>> such way that it does not preclude us from moving towards a clean
>>>>>>> architecture I described during the next iteration.
>>>>>>
>>>>>> Just having a hard time seeing the value. This would be like making
>>>>>> each of the IPA plugins a separate package and somehow installing 
>>>>>> them
>>>>>> individually.
>>>>>>
>>>>>> To do this you'd need at least 2 packages, a high level one with the
>>>>>> "framework" and then a separate one for each data type.
>>>>>>
>>>>>> This could also be achieved, and likely more cleanly, without all
>>>>>> these extra packages, as a simple configuration file. Once a 
>>>>>> package,
>>>>>> always a package.
>>>>>>
>>>>>> Maybe I'm too close to the problem, but to me this is a
>>>>>> Foreman-specific solution. The "smartproxy" is a Foreman creation, I
>>>>>> don't know that anything else is using it. If you want a RESTful
>>>>>> server, then we enable REST in IPA directly, but selectively 
>>>>>> enabling
>>>>>> and disabling APIs is not something we've done before. It has been
>>>>>> controlled by ACIs instead.
>>>>>>
>>>>>> rob
>>>>>>
>>>>>
>>>>> We are trying to predict future here. Say we release it as you 
>>>>> suggest.
>>>>> Tomorrow we point someone upstream who wants to add users to IPA 
>>>>> from a
>>>>> similar proxy to this implementation and say use this as a model.
>>>>> And then Rich needs the same but for DNS for Designate.
>>>>>
>>>>> What would be the best? Rob if you knew that tomorrow two other
>>>>> developers will create similar proxies for users and DNS would you
>>>>> change anything? Would you provide some guidelines to them?
>>>>> If you are close to the problem you should be able to at least tell
>>>>> them: "copy and paste" vs. "add more APIs to the same proxy".
>>>>> If your recommendation is copy and paste then I suspect there will be
>>>>> challenges of running these proxies on the same machine - they will
>>>>> collide on ports and sockets. If we say "extend" shouldn't we use a
>>>>> more
>>>>> generic name?
>>>>>
>>>>
>>>> I'd say "use the existing IPA API". The only reason we have to 
>>>> write the
>>>> smartproxy at all is to interoperate with another service that
>>>> already has a
>>>> well-defined remote server API which uses REST.
>>>>
>>>> rob
>
> +1, this is indeed a Foreman-specific one-off. A real REST API would 
> only look similar on the outside. (But I still see the value in making 
> the responses simulate what a real REST API would look like.)
>
>>> OK, so you think that proxy is one off. OK I am fine with it.
>>> I was under assumption that it would be a beginning of a trend but I
>>> might be
>>> wrong as I do not have valid arguments to prove or disprove one way or
>>> another.
>>> I guess time would show.
>>>
>>> Any objections to Rob's approach?
>>
>> If this is a one off, specifically designed only for Foreman use case,
>> my question is - do we really want to have this as a part of core
>> FreeIPA repo and a part of it's core subpackages? So that when somebody
>> installs all packages from our repo, he gets Foreman one-off installed?
>
> Installed, but definitely not started or configured.
> It's a few small files, I don't think it's worth it to create a whole 
> different repo for them.
>
>> Wouldn't it be better then to keep the FreeIPA smartproxy in a separate
>> package to avoid having FreeIPA core full of one-offs? In my mind,
>> FreeIPA is a general purpose IdM solution and this part does not follow
>> the picture...
>
> Maybe it should go to contrib/ then?
>
>> Just brainstorming here...
>>
>> Martin
>
I do not see a reason to have a separate SRPM. So far it will complicate 
things.
As long as we can install it separately I am fine.

-- 
Thank you,
Dmitri Pal

Sr. Engineering Manager for IdM portfolio
Red Hat Inc.


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