[wildfly-dev] trying to run subsystem extension in host controller

[John Mazzitelli]

<TL;DR>
Trying to run a subsystem extension in host controller and it fails because some of its service dependencies are missing. Am I doing something wrong (it would not be a shocker if I was) or are these services really not deployed inside the Host Controller?
</TL;DR>


I'm trying to get a subsystem extension to run inside of the Host Controller. This is a subsystem extension that runs fine in a standalone WildFly container - just trying to get it to run in a host controller (and maybe later in a domain controller as well).

In domain/configuration/host.xml, I add my own <subsystem> in the <profile> - and that seems to run OK (well, not OK, but I know it is getting its initialization method invoked by the container).

Because I need an outbound socket binding defined, I put add a socket-binding-groups in the host.xml (there are no socket-binding-groups in here by default):

    <socket-binding-groups>
      <socket-binding-group default-interface="public" name="standard-sockets">
          <outbound-socket-binding name="hawkular">
              <remote-destination host="127.0.0.1" port="8080"/>
          </outbound-socket-binding>
      </socket-binding-group>
    </socket-binding-groups>

That causes the container to abort with "WFLYCTL0198: Unexpected element '{urn:jboss:domain:4.0}socket-binding-groups' encountered" So I remove <socket-binding-groups> so that <socket-binding-group> is a direct child of the top-level <host>. The container starts OK when I do this.

But now the problems - my subsystem registers itself with a few service dependencies that do not exist at the time my service is initialized - specifically:

jboss.naming.context.java (o.j.a.naming.deployment.ContextNames.JAVA_CONTEXT_SERVICE_NAME)

jboss.outbound-socket-binding (o.j.a.network.OutboundSocketBinding.OUTBOUND_SOCKET_BINDING_BASE_SERVICE_NAME)

jboss.server.environment (o.j.a.server.ServerEnvironmentService.SERVICE_NAME)

jboss.as.server-controller (o.j.a.server.Services.JBOSS_SERVER_CONTROLLER)

When the host controller runs, I get this startup error:

ERROR [org.jboss.as.controller.management-operation] (Controller Boot Thread) WFLYCTL0013: Operation ("add") failed - address: ([
     ("host" => "master"),
     ("subsystem" => "hawkular-wildfly-agent")
 ]) - failure description: {"WFLYCTL0180: Services with missing/unavailable dependencies" => [
     "\"org.hawkular.agent.\".hawkular-wildfly-agent is missing [jboss.outbound-socket-binding.hawkular, jboss.server.environment, jboss.as.server-controller]",
     "jboss.naming.context.java.abc is missing [jboss.naming.context.java]"
 ]}

Sooo..... my question is - what happens if a subsystem needs these things? Do I need to do something special to make them available or are they really not deployed in the host controller?

What I need these for is:

jboss.naming.context.java - so I can store something in JNDI (actually, for my use case, I can probably skip this dependency - I don't think I will need it when running in the host controller)

jboss.outbound-socket-binding - my subsystem needs to talk to an external server and this defines what host/port that server is on

jboss.server.environment - I need this to find out where the host controller's data directory is (e.g. domain/data). Is there another way to get this?

jboss.as.server-controller - I need this to obtain information from the management model such as "/:uuid" (which it looks like HCs do not have), the "/:launch-type" attribute and others.