[jboss-as7-dev] transaction integration

[David M. Lloyd]

On 09/19/2011 07:44 AM, Jonathan Halliday wrote:
>
> The AS management model is not intended to support all the JTS (or other
> parts of JBossTS) config options. There are over 100 of them in TS as a
> whole. Only the most commonly used ones are exposed. For the others
> there needs to be a general mechanism per AS7-1496.

Note that general configuration mechanisms are not allowed in most 
circumstances.  Either a property is important enough to be a 
first-class part of the schema, or it is not important enough to be a 
part of the supported configuration.

That said, we will allow an unsupported ad-hoc configuration element. 
The element should be called "extension-properties", and the child 
elements should be property elements (e.g. <property name="foo" 
value="bar"/>).

Note that unlike our formal schema, ad-hoc properties do NOT have any 
compatibility or functionality guarantees and are intended as a means by 
which we can deliver fixes which require configuration outside of the 
main schema.  We can drop support for properties at any time; 
unrecognized properties are ignored.

Here are some guidelines as to when to use what:

1. If the property is something that would be set in the default shipped 
configuration, it must be a first-class element, not an extension property.

2. If the property is something that is commonly configured or 
customized, it must be a first-class element, not an extension property.

3. If the property is something that the user should NOT generally be 
accessing or modifying, it should not be a first-class element.  It MAY 
be added as an extension property as needed later on.

I believe that this does mean that we will generally err on the side of 
having many configuration elements.

Also, if we do plan to drop a first-class element, there needs to be a 
deprecation notice ahead of time; this should be planned well in advance.

-- 
- DML