Module Netplex_main

module Netplex_main: sig .. end

Main program for Netplex servers

type cmdline_config

val args : ?defaults:cmdline_config ->
       unit -> (Arg.key * Arg.spec * Arg.doc) list * cmdline_config

let (opt_list, cmdline_cfg) = args(): Returns opt_list for inclusion in the Arg.parse option list. The effects made available by the returned cmdline_cfg value.

The defaults (unless overridden by defaults): The config file is derived from the name of the executable (by appending .conf instead of the current extension). There is no config tree.

defaults : The default argument values

val create : ?config_filename:string ->
       ?config_tree:Netplex_types.config_tree ->
       ?pidfile:string option ->
       ?foreground:bool -> unit -> cmdline_config

Creates the command-line configuration object.

By setting config_tree a special configuration can be injected - the file config_filename is not loaded in this case (but may still appear in error messages)

val modify : ?config_filename:string ->
       ?config_tree:Netplex_types.config_tree ->
       ?pidfile:string option ->
       ?foreground:bool ->
       cmdline_config -> cmdline_config

Modifies the command-line configuration object

val config_filename : cmdline_config -> string

Returns the filename of the configuration file, or the default if it has not been set on the command-line

val config_filename_opt : cmdline_config -> string option

Returns the filename of the configuration file, or None if it has not been set on the command-line

val config_tree_opt : cmdline_config -> Netplex_types.config_tree option

Returns the tree of the configuration file, or None if it has not been set by create or modify. Note that args never sets the config tree.

val pidfile : cmdline_config -> string option

Returns the location of the PID file (if any)

val foreground : cmdline_config -> bool

Returns whether the daemon runs in the foreground

val startup : ?late_initializer:(Netplex_types.config_file ->
                          Netplex_types.controller -> unit) ->
       ?config_parser:(string -> Netplex_types.config_file) ->
       Netplex_types.parallelizer ->
       Netplex_types.logger_factory list ->
       Netplex_types.workload_manager_factory list ->
       Netplex_types.processor_factory list -> cmdline_config -> unit

Establishes a configuration and starts the Netplex daemon.

If a ready-made configuration tree is included in the passed configuration it is taken as the configuration. If otherwise only the name of the config file is available, this file is parsed. Fails with Netplex_config.Config_error when an error in the configuration is detected.

The late_initializer is called after the Netplex controller has been fully initialized, and before the main event loop is entered. You can perform here further initializations, e.g. starting helper threads.

The config_parser is by default Netplex_config.read_config_file. You can override it by whatever parser you would like to use. The parser is only used if a configuration tree is unavailable, and the configuration needs to be loaded from a file.

As side-effect, the current logger of the Netlog module is set to selected Netplex logger. Note that this setting remains active even after startup returns to the caller. Also note that log messages submitted via Netlog appear as from component "netplex.other" if they are sent from outside of a container.

Tutorial

The typical main program for a Netplex server system looks like:

 
   let my_factories = ...

   let start() =
    let opts, cmdconf = Netplex_main.args() in
    Arg.parse 
      opts
      (fun s -> raise(Arg.Bad ("Unknown arg: " ^ s))) 
      "usage: protoserver";
    let par = Netplex_mp.mp() in  (* or Netplex_mt.mt() *)
    Netplex_main.startup
      par
      Netplex_log.logger_factories
      Netplex_workload.workload_manager_factories
      my_factories
      cmdconf

   Sys.set_signal Sys.sigpipe Sys.Signal_ignore;
   start()

This main program enables:

The standard command-line arguments -conf, -pid and -fg are understood
The configuration file is parsed
The configuration can refer to all loggers and workload managers coming with Netplex
The parallelizer is selected: Here, it is multi-processing (Netplex_mp). One could also select multi-threading (Netplex_mt)
The processors defined by my_factories are made available for connection processing

This web site is published by Informatikbüro Gerd Stolpmann

Plasma	GitLab	Archive
Projects	Blog	Knowledge