Hi Brian,
Re the stability level, I'd like to explore the idea of using the server itself as the control point for what features are allowed by tools.
1) The WildFly Galleon Plug has stability notions that can be used when provisioning, to restrict the installation to functionality with a desired stability. Is this surfaced in Prospero?
Yes when provisioning the server the user can use `--stability-level` attribute to define the provisioned server’s stability level.
At the very beginning, Prospero of course comes before the installation, so there does need to be some initial control of stability that's not coming from the installation.
2) This feature is about updating an existing installation. That installation was provisioned with a particular minimum stability. Can this information be preserved in a way that allows Prospero to use it?
Yes, the stability level is a part of the Galleon provisioning definition, it's stored in the .galleon/provisioning.xml. Prospero has an access to that information.
I started down this line of thinking because there shouldn't be any need to start the JBoss CLI or HAL with a particular stability level in order to control the capabilities they expose to users. They connect to a server and can see its stability and can tailor their behavior accordingly. For example if a CLI command or command arg is at preview stability, don't offer it if the server is at community or default.
I guess that would be possible - the argument or operation would still be available to the user when composing the command, but at execution time the user would get an unsupported operation error. I’m wondering if that’d lead to some confusion for the users though if those operations and attributes were available in the help and autocomplete but would not work when executed on the server.
JBoss CLI has the same issue regarding help, as its help text is static. I think it's ok -- the static help text can just be a bit more verbose and explain about the required stability.
In general I wanted to explore the option to include the notion of stability levels in the Prospero Galleon packs, so that we can provision the installer distribution at either level, but I need to understand more about how those levels are implemented in WildFly and Galleon to do that.
A quick primer:
1) 3 interfaces in the controller module org.jboss.as.contoller package -- Feature, FeatureFilter, FeatureRegistry. Particularly Feature, which Extension, ResourceDefintion, AttributeDefinition, OperationDefinition, etc implement, with methods in the related builders to set the stability of the thing if it's not default. This is the mechanism to define the stability of feature pack elements.
2) <property name="jboss.stability" value="preview"/> in a module.xml marks an entire module as being preview stability. This is read by Galleon when making decisions about whether to provision the Galleon package that represents the module. This lets us prevent unwanted bits from even being installed.
Thanks,
Bartosz
-- Brian Stansberry
Principal Architect, Red Hat JBoss EAP
WildFly Project Lead
He/Him/His