Packages

•  package root

  Definition Classes

  root

•  package csw

  Definition Classes

  root

•  package framework

  This project contains the framework for creating components, such as HCDs and Assemblies.

  Framework

  This project contains the framework for creating components, such as HCDs and Assemblies.

  A component is implemented by extending the csw.framework.scaladsl.ComponentHandlers base class. These handlers are executed under an Supervisor Actor: csw.framework.internal.supervisor.SupervisorBehavior and TLA Actor (Top Level Actor): csw.framework.internal.component.ComponentBehavior defined in the framework which handles the lifecycle and supervision of this component.

  Components are controlled by a csw.framework.internal.supervisor.SupervisorBehavior actor that intercepts common messages (ex. Shutdown, Restart) or lifecycle messages (ex. GoOffline or GoOnline) sent from external entities to determine the state of the component.

  Components that are not in the csw.messages.framework.SupervisorLifecycleState.Running state, do not receive csw.messages.CommandMessage.

  When Component is created using this framework, it guarantees that component (HCD/Assembly) is registered with LocationService only when Component moves to csw.messages.framework.SupervisorLifecycleState.Running state. That means, one component can resolve other component only when its in Running state and ready to accept messages.CommandMessage

  Important Actors in Framework

  - csw.framework.internal.supervisor.SupervisorBehavior : Each component created by this framework is supervised by this actor.

  Default strategy of supervisor is to stop child actor but depending on nature of the failure, the supervisor has a choice of the following two options:

  • csw.framework.exceptions.FailureRestart : Restart the child actor i.e. kill the current child actor that failed and create a new one in its place
  • csw.framework.exceptions.FailureStop : Stop the child actor permanently

  Supervisor changes its csw.messages.framework.SupervisorLifecycleState based on the messages it receives. Decision to handle external messages or not is taken by the supervisor based on its current csw.messages.framework.SupervisorLifecycleState. For complete list of supported messages per csw.messages.framework.SupervisorLifecycleState, see csw-messages project.

  - csw.framework.internal.component.ComponentBehavior : Like Supervisor, evey component is associate with this actor which is known as TLA (Top Level Actor) And it also maintains its own state csw.framework.internal.component.ComponentLifecycleState based on messages it receives.

  Main purpose of this actor is to invoke component specific code written in their corresponding handlers. This is where framework code meets Component specific code.

  - csw.framework.internal.pubsub.PubSubBehavior : This actor is created by framework which is wrapped into csw.framework.CurrentStatePublisher for easy interaction with this actor and then passed to component handlers so that component can publish their csw.messages.params.states.CurrentState.

  If one component (ex. Assembly) is interested in csw.messages.params.states.CurrentState published by other component (ex. HCD) then Assembly can subscribe to HCD's current state.

  PubSub actor maintains the list of subscribers and keeps publishing csw.messages.params.states.CurrentState to all subscribers.

  - csw.framework.internal.container.ContainerBehavior : When multiple components needs to be started in container, then this actor is created. Job of this actor is just to logically group multiple components and support csw.messages.SupervisorContainerCommonMessages. It receives csw.messages.SupervisorContainerCommonMessages.Shutdown or csw.messages.SupervisorContainerCommonMessages.Restart message and forwards it to all the components residing in this container.

  deploy package

  - csw.framework.deploy.containercmd.ContainerCmd : ContainerCmd is a helper utility provided by framework to start multiple components in container mode or single component in Standalone mode.

  Example of Container Config File

  Here is an example of a config file for creating a container with the name IRIS_Container that contains one assembly (named Filter) and depends on the services of two HCDs (Instrument_Filter and Disperser). Factory class for assembly is csw.common.components.framework.SampleComponentBehaviorFactory. A Supervisor actor will be created to manage the assembly, which includes registering it with the location service, using the given name and prefix. The prefix can be used to distribute parts of the configurations to different HCDs. HCDs register themselves with the Location Service and specify a unique prefix that can be used for this purpose.

  name = "IRIS_Container"
  components: [
    {
      name = "Filter"
      componentType = assembly
      behaviorFactoryClassName = csw.common.components.framework.SampleComponentBehaviorFactory
      prefix = tcs.mobie.blue.filter
      locationServiceUsage = RegisterOnly
      connections = [
        {
          name: Instrument_Filter
          componentType: hcd
          connectionType: akka
        },
        {
          name: Disperser
          componentType: hcd
          connectionType: akka
        }
      ]
    },
    {
      name = "Instrument_Filter"
      componentType = hcd
      behaviorFactoryClassName = csw.common.components.framework.SampleComponentBehaviorFactory
      prefix = tcs.mobie.blue.filter
      locationServiceUsage = RegisterOnly
    },
    {
      name = "Disperser"
      componentType: hcd
      behaviorFactoryClassName: csw.common.components.framework.SampleComponentBehaviorFactory
      prefix: tcs.mobie.blue.disperser
      locationServiceUsage = RegisterOnly
    }
  ]

  Example of Standalone Config File

  name = "IFS_Detector"
  componentType = hcd
  behaviorFactoryClassName = csw.common.components.framework.SampleComponentBehaviorFactory
  prefix = iris.ifs
  locationServiceUsage = RegisterOnly
  connections = []

  - csw.framework.deploy.hostconfig.HostConfig : This is just a helper to create host configuration application. This support starting multiple containers on a given host machine and each container will have single/multiple components.

  Example of Host Config file

  # This is a host configuration file which contains list of containers to be spawned by host configuration app
  containers: [
      {
        # mode can be one of Container or Standalone
        mode: "Container"
        # path of individual container configuration file
        configFilePath: "/resources/assemblyContainer.conf"
        # provide 'Remote' if file needs to fetched from config service else
        # provide 'Local' to fetch file from local machine
        configFileLocation: "Local"
      },
      {
        mode: "Standalone"
        configFilePath: "/resources/hcdStandalone.conf"
        configFileLocation: "Local"
      }
  ]

  Definition Classes

  csw

•  package exceptions

  Definition Classes

  framework

• FailureRestart
• FailureStop

csw.framework.exceptions

FailureStop 