nns_server man page

nameserv::server — Name service facility, Server

Synopsis

package require Tcl 8.4

package require nameserv::server ?0.3.2?

package require comm

package require interp

package require logger

::nameserv::server::start

::nameserv::server::stop

::nameserv::server::active?

::nameserv::server::cget -option

::nameserv::server::configure

::nameserv::server::configure -option

::nameserv::server::configure -option value...

Description

Please read Name service facility, introduction first.

This package provides an implementation of the serviver side of the name service facility queried by the client provided by the package nameserv. All information required by the server will be held in memory. There is no persistent state.

This service is built in top of and for the package comm. It has nothing to do with the Internet's Domain Name System. If the reader is looking for a package dealing with that please see Tcllib's packages dns and resolv.

This server supports the Core protocol feature, and since version 0.3 the Search/Continuous feature as well.

API

The package exports five commands, as specified below:

::nameserv::server::start
This command starts the server and causes it to listen on the configured port. From now on clients are able to connect and make requests. The result of the command is the empty string.

Note that any incoming requests will only be handled if the application the server is part of does enter an event loop after this command has been run.
::nameserv::server::stop
Invoking this command stops the server and releases all information it had. Existing connections are shut down, and no new connections will be accepted any longer. The result of the command is the empty string.
::nameserv::server::active?
This command returns a boolean value indicating the state of the server. The result will be true if the server is active, i.e. has been started, and false otherwise.
::nameserv::server::cget -option
This command returns the currently configured value for the specified -option. The list of supported options and their meaning can be found in section Options.
::nameserv::server::configure
In this form the command returns a dictionary of all supported options, and their current values. The list of supported options and their meaning can be found in section Options.
::nameserv::server::configure -option
In this form the command is an alias for "::nameserv::server::cget -option]". The list of supported options and their meaning can be found in section Options.
::nameserv::server::configure -option value...
In this form the command is used to configure one or more of the supported options. At least one option has to be specified, and each option is followed by its new value. The list of supported options and their meaning can be found in section Options.

This form can be used only if the server is not active, i.e. has not been started yet, or has been stopped. While the server is active it cannot be reconfigured.

Options

The options supported by the server are for the specification of the TCP port to listen on, and whether to accept non-local connections or not. They are:

-localonly bool
This option specifies whether to accept only local connections (-localonly 1) or remote connections as well (-localonly 0). The default is to accept only local connections.
-port number
This option specifies the port the name service will listen on after it has been started. It has to be a positive integer number (> 0) not greater than 65536 (unsigned short). The initial default is the number returned by the command ::nameserv::server::common::port, as provided by the package ::nameserv::server::common.

History

0.3
Extended the server with the ability to perform asynchronous and continuous searches.
0.2
Changed name of -local switch to -localonly.
0.1
Initial implementation of the server.

Bugs, Ideas, Feedback

This document, and the package it describes, will undoubtedly contain bugs and other problems. Please report such in the category nameserv of the Tcllib Trackers [http://core.tcl.tk/tcllib/reportlist]. Please also report any ideas for enhancements you may have for either package and/or documentation.

See Also

nameserv::client(n), nameserv::common(n)

Keywords

name service, server

Category

Networking

Info

0.3.2 tcllib Name service facility