On 14.06.2011, at 22:45, Bill Shannon wrote:
> Adam Bien wrote on 06/14/11 12:13 PM:
>>
>> On 13.06.2011, at 22:48, Bill Shannon wrote:
>>
>>> We discussed this "staging" concept quite a bit internally for EE 6.
>>> In the end we left it out of the platform because it didn't seem to
>>> solve any problem that couldn't already be solved using other existing
>>> mechanisms, at least as it was being proposed at the time.
>>>
>>> We found *very* few cases where the behavior of existing APIs would
>>> change based on what "stage" you were in. About the best we came up
>>> with was that some web application errors might want to produce more
>>> useful output when in development stage. But since we specify very
>>> little about what such output should contain, products already have
>>> the flexibility to vary their behavior in this regard.
>>>
>>> If the behavior of the platform APIs don't change based on the stage,
>>> what is it used for? Well, applications could change their behavior
>>> based on the stage, but they can already do that using an appropriate
>>> JNDI environment variable of their own choosing; we didn't really need
>>> to specify that.
>>
>> But then you will have to change the application code. With stage dependent application server settings you
>> would modify the application server settings, without touching the application.
>
> Well, you have to change the application code to read the variable and
> make use of it, but once you do that you can set different values of
> the variable without changing the application.
I meant: you do not have to change the application to move it from one stage to another.
>
>>> One idea we did consider was to have different resource settings based
>>> on the stage. You might bind to one database for testing and another
>>> for production, for instance. Since it's already possible for the
>>> deployer to do these different mappings at deployment time, this seemed
>>> like it would only really be useful if you could specify more details
>>> about the resource you were mapping to, as you can with DataSourceDefinition.
>>
>> I actually never saw a dedicated deployer role in my projects. There is the "operation" role, but they usually
>> do not care about the application internals.
>>
>> What is the experience of the other consultants (Antonio, Reza and Co:-))?
>>
>>>
>>> Allowing different resource configurations for different stages
>>> required more changes to the deployment descriptors than we were
>>> willing to consider for EE 6. Since we knew that we wanted to consider
>>> major changes to deployment descriptors in the future, this was another
>>> reason to defer defining anything about stages for EE 6.
>> Or we could standardize the Resource settings (e.g. connection pools) on the application server side and make them stage dependent.
>
> That's one of the things we should look at for EE 7.
This would be useful. Especially the standardization part.