On Thu, Sep 15, 2016 at 2:21 PM, Brian Stansberry <
brian.stansberry(a)redhat.com> wrote:
I’m adding wildfly-dev in cc.
Yes, the names of the parameters are ambiguous. And it’s not necessary for
them to be ambiguous, as the “alternatives”, “required” and “requires"
stuff lets us use clearly named params for different cases:
“attribute” — required=true, alternatives=[parameter]
“parameter - required=true, alternatives=[attribute], requires=[operation]
“operation” - required=false
An alternative is we could just drop all of those. The operation and
attribute params are not necessary if the client has already done a
read-resource-description or read-operation-description and already knows
the value of the “capability-reference” descriptor. Then it could simply be
/core-service=capability-registry:suggest-capabilities(
address=[(subsystem=foo),(child=bar)],static-name=org.
wildfly.network.socket-binding)
{
“outcome” => “success”,
“result” => [
“http”,
“https”
]
}
From the console's perspective that version would work best for
us.
However I see one issue using this approach: If there are multiple
suggestions having the same name while referring to different resources.
This typically happens with attributes which have a capability reference to
"org.wildfly.network.socket-binding" (for instance attribute
"socket-binding" in "/subsystem=remoting/connector=*").
Using
/core-service=capability-registry:get-provider-points(name=org.wildfly.network.socket-binding)
returns "/socket-binding-group=*/socket-binding=*" which resolves to
several "http" socket-bindings in different socket-binding-groups.
Just using the names as suggestions would end up in several "http"
suggestions. What we do in that case in the console is to show some context:
standard-sockets / http
ha-sockets / http
full-sockets / http
...
When thinking about this we should remember the dot/bracket syntax we
allow for updating details of complex attributes via write-attribute:
:write-attribute(name=complex.nested[2].field,value=http)
For the CLI, just passing through “attribute”=>"complex.nested[2].field”
is easier as there is no need for it to unpack the ‘.’ and ‘[]' syntax and
find the description of ‘field’ and get the capabiity-reference.
For the console, it may be easier to get the capability-reference and pass
it instead. Easier than going from some code backing a gui widget and
synthesizing "complex.nested[2].field” to pass to the server.
> On Sep 15, 2016, at 6:40 AM, Jean-Francois Denise <jdenise(a)redhat.com>
wrote:
>
> The operation argument is an optional argument that contains the
resource operation name. In case the operation is present, the attribute
argument means operation argument. Otherwise the attribute contains the
name of an attribute. This is a draft of operation, the operation naming
could be reviewed.
> I don't think that this operation updates the capabilities registry,
this is a readonly operation to retrieve capabilities.
> JF
>
> On 15/09/16 12:41, Harald Pehl wrote:
>> That looks very promising. Having such an operation would also cover
the requirements of HAL. What's behind the "operation" parameter? Does it
allow add / modify?
>>
>> On Thu, Sep 15, 2016 at 12:04 PM, Jean-Francois Denise <
jdenise(a)redhat.com> wrote:
>> Hi,
>>
>> I have spent some time looking at the semantic of the capability scopes
(thanks to Brian help).
>> A client "could" try to base its capability resolution by looking at
capabilities present in the capabilities registry. Scope can be very
complex, are possibly not fully modeled yet, and semantic could evolve in
the future. So difficult for a client to rely on scopes to
resolve the accessible capabilities.
>>
>> The server side has the logic to check the capabilities and could
expose part of its engine logic to clients for capabilities resolution.
Brian is proposing that the capabilities registry would expose a new
operation:
>> /core-service=capability-registry:suggest-capabilities(
address=[(subsystem=foo),(child=bar)],operation=add,
>> attribute=socket-binding)
>> {
>> “outcome” => “success”,
>> “result” => [
>> “http”,
>> “https”
>> ]
>> }
>>
>> It seems that the CLI "completion requirements" would be covered by
this addition. I am wandering if it would also cover the HAL ones?
>>
>> Thanks.
>>
>> JF
>>
>>
>> On 13/09/16 21:50, Harald Pehl wrote:
>>> See my answers inline.
>>> On Tue, Sep 13, 2016 at 12:04 PM, Jean-Francois Denise <
jdenise(a)redhat.com> wrote:
>>> Hi Claudio and Harald, thank you for your reply. Some questions
in-lined. I am just discovering the capabilities topic ;-) On 12/09/16
19:47, Claudio Miranda wrote:
>>> Your suggested approach looks similar to the way HAL does, however
there are some differences. 1) There are many attributes that doesn't
declare the capability-reference, (example: subsystem=transactions,
attribute jdbc-store-datasource), then we emulate it.
>>> How do you emulate this? You are hard coding the list of attributes
that are reference to capabilities? You can point me to some code? Harald,
what is the technical difficulty there? Are they real capabilities? If the
referenced resource can't register capabilities, are they actual
capabilities?
>>> We have an internal registry [1] which is basically a map with the
capability name as key and a class holding information about the capability
as value [2]. Most entries in our registry are taken from
/core-service=capability-registry, but to provide the capabilities also
for WildFly < 11, we need to manually add entries to our registry during
startup [3].
>>>
>>> 2) The capabilities and addresses are associated at bootstrap, this
way HAL associates all capability-reference names to the target address it
should lookup on at runtime.
https://github.com/hal/core/blob/
26bb90653f60cfad2f3c3aac5964c4f125e18777/gui/src/main/java/
org/jboss/as/console/client/meta/CoreCapabilitiesRegister.java
>>> This is the information that the capabilities registry contains?
Right? I should be able to retrieve all that from the registry?
>>> Yes we read everything from /core-service=capability-registry
>>> 3) For domain mode, the attributes that declares capabilities
resources out of profile, as socket-bindings, there is a small
inconvenient, we need to display the full resource address, as there is no
way to associate the profile to the socket-binding, we need to show all
socket-binding of all socket-binding-groups, see
http://i.imgur.com/86VP1F9.png
>>> The /<profile>/subsystem=transactions/process-id-socket-binding
should be tagged with "capability-reference". Right? And it doesn't seem
to
be. Do you now the rational?
>>> Right, the r-r-d result for /<profile>/subsystem=transactions does
not contain a "capabilities-reference" for the attribute
"process-id-socket-binding". This seems to be a bug in the transactions
subsystem. But actually it's a good example how we can still provide
typeahead support for attributes which do not have a "capability-reference"
info [4]. This does not involve the capabilities registry. It's just about
adding typeahead support for attributes which reference some other
resources, but do not yet have a "capabilities-reference"
>>> Once the user has chosen a value, what are you setting as the value
for the process-id-socket-binding attribute? Harald, you are saying that
the resource name is taken as form input. So it means that only the last
part of the resource address is stored? For example only "ajp"? Is it
enough to fully identify the actual resource? Don't you need (full
capabilities name + scope)?
>>> Yes that's right, only the resource name is stored. Let's take the
server-group resource as an example. It has the attribute "profile" which
declares the "capability-reference" "org.wildfly.domain.profile".
When
adding the resource, only the profile name is stored. AIUI to identify /
verify the profile the attribute value and the information from the
capabilities-regisrty are used.
>>>
>>> Thank-you.
>>> [1]
https://github.com/hal/hal.next/blob/develop/meta/src/
main/java/org/jboss/hal/meta/capabilitiy/Capabilities.java
>>> [2]
https://github.com/hal/hal.next/blob/develop/meta/src/
main/java/org/jboss/hal/meta/capabilitiy/Capability.java
>>> [3]
https://github.com/hal/hal.next/blob/develop/app/src/
main/java/org/jboss/hal/client/bootstrap/functions/
ReadCapabilities.java#L65
>>> [4]
https://github.com/hal/hal.next/blob/develop/app/src/
main/resources/org/jboss/hal/client/configuration/subsystem/transactions/
TransactionView.mbui.xml#L47
>>> --- Harald Pehl JBoss by Red Hat
http://hpehl.info
>> --
>> --- Harald Pehl JBoss by Red Hat
http://hpehl.info
--
Brian Stansberry
Manager, Senior Principal Software Engineer
JBoss by Red Hat