Ocamlnet 3 Reference Manual : Netplex_types.controller

# Class type Netplex_types.controller

    class type controller = object .. end

The controller is the object in the Netplex master process/thread that manages the containers, logging, and service definitions

    method ptype : parallelization_type

The actually effective parallelization type

    method sys_id : thread_sys_id

The thread running the controller

    method controller_config : controller_config

    method services : (socket_service * socket_controller *
            workload_manager)
           list

The list of controlled services

    method add_service : socket_service -> workload_manager -> unit

Adds a new service. Containers for these services will be started soon. It is allowed to add several services with the same name (but it will be hard to distinguish them later).

    method add_message_receiver : ctrl_message_receiver -> unit

Adds a message receiver. This receiver runs in the context of the controller and receives all messages sent to it. The `name` method must return the name.

    method add_plugin : plugin -> unit

Adds a plugin. If the plugin object has already been added, this is a no-op.

Plugins must have been added before the first container is started. This is not checked, however. You are on the safe side when the plugin is added in the `create_processor` factory method, or in the `post_add_hook` of the processor.

    method add_admin : (Rpc_server.t -> unit) -> unit

`add_admin setup`: Allows to bind another RPC program to the admin socket. The function `setup` will be called whenever a connection to the admin socket is established, and this function can call `Rpc_server.bind` to bind another RPC program. By default, only the `Admin` interface is available as described in `netplex_ctrl.x`.

Note that this RPC server runs in the scope of the controller! No additional process or thread is created.

    method logger : logger

The logger

    method event_system : Unixqueue.unix_event_system

The event system used by the controller. It must not be used from a container.

    method restart : unit -> unit

Initiates a restart of all containers: All threads/processes are terminated and replaced by newly initialized ones.

    method shutdown : unit -> unit

Initiates a shutdown of all containers. It is no longer possible to add new services. When the shutdown has been completed, the controller will terminate itself. Note that the shutdown is performed asynchronously, i.e. this method returns immediately, and the messaging required to do the shutdown is done in the background.

    method send_message : string -> string -> string array -> unit

`send_message destination msgname msgargs`: Sends a message to `destination`. When this method returns, it is only ensured that the receivers registered in the controller have been notified about the message (so it can be made sure that any newly forked containers know about the message). It is not guaranteed that the existing containers are notified when this method returns. This can (and usually will) happen at any time in the future.

    method send_admin_message : string -> string -> string array -> unit

`send_message destination msgname msgargs`: Sends an admin message to `destination`.

See `send_message` for the notification guarantees.

    method register_lever : (controller -> encap -> encap) ->
           int

`let id = register_lever f`: It is possible to register a function `f` in the controller, and run it over the internal RPC interface from any container. These functions are called levers. See `activate_lever` below. See also `Netplex_cenv.Make_lever` for a convenient way to create and use levers.

    method activate_lever : int -> encap -> encap

Runs the registered lever directly

    method containers : container_id list

Lists the containers

    method containers_for : string -> container_id list

Lists the containers for a certain socket service name

    method container_count : string -> int

The number of containers for a certain socket service name

    method free_resources : unit -> unit

Should be called when the controller is finished, in order to free resources again. E.g. plugins are unplugged, and the master sockets are closed.

    method startup_directory : string

The current directory at startup time