orber

MODULE

orber

MODULE SUMMARY

The main module of the Orber application

DESCRIPTION

This module contains the functions for starting and stopping the application. It also has some utility functions to get some of the configuration information from running application.

EXPORTS

start() -> ok

Starts the Orber application (it also starts mnesia if it's not running).

stop() -> ok

Stops the Orber application.

domain() -> string()

This function returns the domain name of the current Orber domain as a string.

iiop_port() -> int()

This function returns the portnumber, which is used by the IIOP protocol. It can be configured by setting the application variable iiop_port, if it's not set it will have the default number 4001.

iiop_timeout() -> int() (milliseconds)

This function returns the timeout value after which outgoing IIOP requests terminate. It can be configured by setting the application variable iiop_timeout TimeVal (seconds), if it's not set it will have the default value infinity. If a request times out a COMM_FAILURE exception is raised.

Note: the iiop_timeout configuration parameter (TimeVal) may only range between 0 and 1000000 seconds. Otherwise, the default value is used.

bootstrap_port() -> int()

This function returns the portnumber, which is used by the CORBA bootstrapping protocol. This protocol is used to fetch an initial reference from another ORB. It can be configured by setting the application variable bootstrap_port, if it's not set it will use the iiop port.

Note: In the future it will use the port number which is set in the standard (the suggestion is 900). Because the standard isn't ready in this area we in the meantime uses a port number, which don't require root permissions in Unix.

orber_nodes() -> RetVal

Types:
RetVal = [node()]

This function returns the list of nodenames that this orber domain consists of.

install(NodeList) -> ok
install(NodeList, Options) -> ok

Types:
NodeList = [node()]
Options = [Option]
Option = {install_timeout, Timeout} | {ifr_storage_type, TableType}
Timeout = infinity | integer()
TableType = disc_copies | ram_copies

This function installs all the necessary mnesia tables and load default data in some of them. If one or more Orber tables already exists the installation fails. The function uninstall may be used, if it is safe, i.e., no other application is running Orber.

Preconditions:

• a mnesia schema must exist before the installation
• mnesia is running on the other nodes if the new installation shall be a multinode domain

Mnesia will be started by the function if it's not already running on the installation node and if it was started it will be stopped afterwards.

The options that can be sent to the installation program is:

• {install_timeout, Timeout} - this timeout is how long we will wait for the tables to be created. The Timeout value can be infinity or an integer number in milliseconds. Default is infinity.
• {ifr_storage_type, TableType} - this option sets the type of tables used for the interface repository. The TableType can be disc_copies or ram_copies. Default is disc_copies. (All other tables in Orber are ram copies).

uninstall() -> ok

This function stops the Orber application, terminates all server objects and removes all Orber related mnesia tables.

Note: Since other applications may be running on the same node using mnesia uninstall will not stop the mnesia application.

add_node(Node, StorageType) -> RetVal

Types:
Node = node()
StorageType = disc_copies | ram_copies
RetVal = ok | exit()

This function add given node to a existing Orber node group and starts Orber on the new node. orber:add_node is called from a member in the Orber node group.

Preconditions for new node:

• erlang started on the new node using the option -mnesia extra_db_nodes, e.g., erl -sname new_node_name -mnesia extra_db_nodes ConnectToNodes_List
• mnesia is running on the new node (no new schema created).
• if the new node will use disc_copies the schema type must be changed using: mnesia:change_table_copy_type(schema, node(), disc_copies)

Orber will be started by the function on the new node.

Fails if:

• Orber already installed on given node
• Mnesia not started as described above on the new node
• Impossible to copy data in Mnesia tables to the new node
• Not able to start Orber on the new node.

The function do not remove already copied tables after a failure. Use orber:remove_node to remove these tables.

remove_node(Node) -> RetVal

Types:
Node = node()
RetVal = ok | exit()

This function removes given node from a Orber node group. The Mnesia application is not stopped.

AUTHORS

Lars Thorsén - support@erlang.se