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
start(Type) -> ok

Types:

Type = temporary | permanent

Starts the Orber application (it also starts mnesia if it is not running). Which Type parameter is supplied determines the behavior. If not supplied Orber is started as temporary. See the Reference Manual application(3) for further information.

jump_start(Attributes) -> ok | {'EXIT', Reason}

Types:

Attributes = Port | Options

Port = integer()

Options = [{Key, Value}]

Key = any key listed in the configuration chapter

Value = allowed value associated with the given key

Installs and starts the Orber and the Mnesia applications with the configuration parameters domain and iiop_port set to "IP-number:Port" and the supplied Port respectively. Theses settings are in most cases sufficient to ensure that no clash with any other Orber instance occur. If this operation fails, check if the listen port (iiop_port) is already in use. This function MAY ONLY be used during development and tests; how Orber is configured when using this operation may change at any time without warning.

stop() -> ok

Stops the Orber application.

info() -> ok
info(IoType) -> ok | {'EXIT', Reason} | string()

Types:

IoType = info_msg | string | io | {io, IoDevice}

Generates an Info Report, which contain Orber's configuration settings. If no IoType is supplied, info_msg is used (see the error_logger documentation). When the atom string is supplied this function will return a flat list. For io and {io, IoDevice}, io:format/1 and io:format/3 is used respectively.

exception_info(Exception) -> {ok, string()} | {error, Reason}

Returns a printable string, which describes the supplied exception in greater detail. Note, this function is mainly intended for system exceptions.

is_system_exception(Exception) -> true | false

Returns true if the supplied exception is a system defined exception, otherwise false.

get_tables() -> [Tables]

Returns a list of the Orber specific Mnesia tables. This list is required to restore Mnesia if it has been partitioned.

get_ORBInitRef() -> string() | undefined

This function returns undefined if we will resolve references locally, otherwise a string describing which host we will contact if the Key given to corba:resolve_initial_references/1 matches the Key set in this configuration variable. For more information see the user's guide.

get_ORBDefaultInitRef() -> string() | undefined

This function returns undefined if we will resolve references locally, otherwise a string describing which host, or hosts, from which we will try to resolve the Key given to corba:resolve_initial_references/1. For more information see the user's guide.

domain() -> string()

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

iiop_port() -> int()

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

iiop_out_ports() -> 0 | {Min, Max}

The return value of this operation is what the configuration parameter iiop_out_ports has been set to.

iiop_out_ports_random() -> true | false

Return the value of the configuration parameter iiop_out_ports_random.

iiop_out_ports_attempts() -> int()

Return the value of the configuration parameter iiop_out_ports_attempts.

iiop_ssl_port() -> int()

This function returns the port-number, which is used by the secure IIOP protocol. It can be configured by setting the application variable iiop_ssl_port, if it is not set it will have the default number 4002 if Orber is to configured to run in secure mode. Otherwise it returns -1.

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 is not set it will have the default value infinity. If a request times out a system exception, e.g. TIMEOUT, is raised.

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

Note: Earlier IC versions required that the compile option {timeout,"module::interface"}, was used, which allow the user to add an extra timeout parameter, e.g., module_interface:function(ObjRef, Timeout, ... Arguments ...) or module_interface:function(ObjRef, [{timeout, Timeout}], ... Arguments ...), instead of module_interface:function(ObjRef, ... Arguments ...). This is no longer the case and if the extra Timeout is used, argument will override the configuration parameter iiop_timeout. It is, however, not possible to use infinity to override the Timeout parameter. The Timeout option is also valid for objects which resides within the same Orber domain.

iiop_connection_timeout() -> int() (milliseconds)

This function returns the timeout value after which outgoing IIOP connections terminate. It can be configured by setting the application variable iiop_connection_timeout TimeVal (seconds), if it is not set it will have the default value infinity. The connection will not be terminated if there are pending requests.

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

iiop_connections() -> Result
iiop_connections(Direction) -> Result

Types:

Direction = in | out | inout

Result = [{Host, Port}] | [{Host, Port, Interface}] | {'EXIT',Reason}

Host = string()

Port = integer()

Interface = string()

Reason = term()

The list returned by this operation contain tuples of remote hosts/ports Orber is currently connected to. If no Direction is not supplied, both incoming and outgoing connections are included.

If a specific local interface has been defined for the connection, this will be added to the returned tuple.

iiop_connections_pending() -> Result

Types:

Result = [{Host, Port}] | [{Host, Port, Interface}] | {'EXIT',Reason}

Host = string()

Port = integer()

Interface = string()

Reason = term()

In some cases a connection attempt (i.e. trying to communicate with another ORB) may block due to a number of reasons. This operation allows the user to check if this is the case. The returned list contain tuples of remote hosts/ports. Normally, the list is empty.

If a specific local interface has been defined for the connection, this will be added to the returned tuple.

iiop_in_connection_timeout() -> int() (milliseconds)

This function returns the timeout value after which incoming IIOP connections terminate. It can be configured by setting the application variable iiop_in_connection_timeout TimeVal (seconds), if it is not set it will have the default value infinity. The connection will not be terminated if there are pending requests.

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

iiop_acl() -> Result

Types:

Result = [{Direction, Filter}] | [{Direction, Filter, [Interface]}]

Direction = tcp_in | ssl_in | tcp_out | ssl_out

Filter = string()

Interface = string()

Returns the ACL configuration. The Filter uses a extended format of Classless Inter Domain Routing (CIDR). For example, "123.123.123.10" limits the connection to that particular host, while "123.123.123.10/17" allows connections to or from any host equal to the 17 most significant bits. Orber also allow the user to specify a certain port or port range, for example, "123.123.123.10/17#4001" and "123.123.123.10/17#4001/5001" respectively. IPv4 or none compressed IPv6 strings are accepted.
The list of Interfaces, IPv4 or IPv6 strings, are currently only used for outgoing connections and may only contain one address. If set and access is granted, Orber will use that local interface when connecting to the other ORB. The module orber_acl provides operations for evaluating the access control for filters and addresses.

activate_audit_trail() -> Result
activate_audit_trail(Verbosity) -> Result

Types:

Verbosity = stealth | normal | verbose

Result = ok | {error, Reason}

Reason = string()

Activates audit/trail for all existing incoming and outgoing IIOP connections. The Verbosity parameter, stealth, normal or verbose, determines which of the built in interceptors is used (orber_iiop_tracer_stealth, orber_iiop_tracer_silent or orber_iiop_tracer respectively). If no verbosity level is supplied, then the normal will be used.

In case Orber is configured to use other interceptors, the audit/trail interceptors will simply be added to that list.

deactivate_audit_trail() -> Result

Types:

Result = ok | {error, Reason}

Reason = string()

Deactivates audit/trail for all existing incoming and outgoing IIOP connections. In case Orber is configured to use other interceptors, those will still be used.

add_listen_interface(IP, Type) -> Result
add_listen_interface(IP, Type, Port) -> Result
add_listen_interface(IP, Type, ConfigurationParameters) -> Result

Types:

IP = string

Type = normal | ssl

Port = integer() > 0

ConfigurationParameters = [{Key, Value}]

Value = as described in the User's Guide or below

Result = {ok, Ref} | {error, Reason} | {'EXCEPTION', #'BAD_PARAM'{}}

Ref = #Ref

Reason = string()

Create a new process that handle requests for creating a new incoming IIOP connection via the given interface and port. If the latter is excluded, Orber will use the value of the iiop_port or iiop_ssl_port configuration parameters. The Type parameter determines if it is supposed to be IIOP or IIOP via SSL. If successful, the returned #Ref shall be passed to orber:remove_listen_interface/1 when the connection shall be terminated.

It is also possible to supply configuration parameters that override the global configuration. The iiop_in_connection_timeout, iiop_max_fragments, iiop_max_in_requests and interceptors parameters simply overrides the global counterparts (See the Configuration chapter in the User's Guide). But for the following parameters there are a few restrictions:

flags - currently it is only possible to override the global setting for the Use Current Interface in IOR and Exclude CodeSet Component flags.
ip_family - can be set to inet or inet6 and is used to get a listen interface that uses another IP version than the default set with flags at startup.
iiop_port - requires that Use Current Interface in IOR is activated and the supplied Type is normal. If so, exported IOR:s will contain the IIOP port defined by this configuration parameter. Otherwise, the global setting will be used.
iiop_ssl_port - almost equivalent to iiop_port. The difference is that Type shall be ssl and that exported IOR:s will contain the IIOP via SSL port defined by this configuration parameter.

If it is not possible to add a listener based on the supplied interface and port, the error message is one of the ones described in inet and/or ssl documentation.

remove_listen_interface(Ref) -> ok

Types:

Ref = #Ref

Terminates the listen process, associated with the supplied #Ref, for incoming a connection. The Ref parameter is the return value from the orber:add_listen_interface/2/3 operation. When terminating the connection, all associated requests will not deliver a reply to the clients.

close_connection(Connection) -> Result
close_connection(Connection, Interface) -> Result

Types:

Connection = Object | [{Host, Port}]

Object = #objref (external)

Host = string()

Port = string()

Interface = string()

Result = ok | {'EXCEPTION', #'BAD_PARAM'{}}

Will try to close all outgoing connections to the host/port combinations found in the supplied object reference or the given list of hosts/ports. If a #'IOP_ServiceContext'{} containing a local interface has been used when communicating with the remote object (see also Module_Interface), that interface shall be passed as the second argument. Otherwise, connections via the default local interface, will be terminated.

Note

Since several clients maybe communicates via the same connection, they will be affected when invoking this operation. Other clients may re-create the connection by invoking an operation on the target object.

secure() -> no | ssl

This function returns the security mode Orber is running in, which is either no if it is an insecure domain or the type of security mechanism used. For the moment the only security mechanism is ssl. This is configured by setting the application variable secure.

ssl_server_options() -> list()

This function returns the list of SSL options set for the Orber domain as server. This is configured by setting the application variable ssl_server_options.

ssl_client_options() -> list()

This function returns the list of SSL options used in outgoing calls in the current process. The default value is configured by setting the application variable ssl_client_options.

set_ssl_client_options(Options) -> ok

Types:

Options = list()

This function takes a list of SSL options as parameter and sets it for the current process.

objectkeys_gc_time() -> int() (seconds)

This function returns the timeout value after which after which terminated object keys, related to servers started with the configuration parameter {persistent, true}, will be removed. It can be configured by setting the application variable objectkeys_gc_time TimeVal (seconds), if it is not set it will have the default value infinity.

Objects terminating with reason normal or shutdown are removed automatically.

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

orber_nodes() -> RetVal

Types:

RetVal = [node()]

This function returns the list of node names 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} | {nameservice_storage_type, TableType} | {initialreferences_storage_type, TableType} | {load_order, Priority}

Timeout = infinity | integer()

TableType = disc_copies | ram_copies

Priority = integer()

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 multi node domain

Mnesia will be started by the function if it is 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.
{initialreferences_storage_type, TableType} - this option sets the type of table used for storing initial references. The TableType can be disc_copies or ram_copies. Default is ram_copies.
{nameservice_storage_type, TableType} - the default behavior of Orber is to install the NameService as ram_copies. This option makes it possible to change this to disc_copies. But the user should be aware of that if a node is restarted, all local object references stored in the NameService is not valid. Hence, you cannot switch to disc_copies and expect exactly the same behavior as before.
{load_order, Priority} - per default the priority is set to 0. Using this option it will change the priority of in which order Mnesia will load Orber internal tables. For more information, consult the Mnesia documentation.

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, Options) -> RetVal

Types:

Node = node()

Options = IFRStorageType | [KeyValue]

IFRStorageType = StorageType

StorageType = disc_copies | ram_copies

KeyValue = {ifr_storage_type, StorageType} | {initialreferences_storage_type, StorageType} | {nameservice_storage_type, StorageType} | {type, Type}

Type = temporary | permanent

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
The new node's domain name is the same for the nodes we want to connect to.
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, due to, for example, the iiop_port is already in use.

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.

configure(Key, Value) -> ok | {'EXIT', Reason}

Types:

Value = allowed value associated with the given key

This function allows the user to configure Orber in, for example, an Erlang shell. It is possible to invoke configure at any time the keys specified above.

Any other key must be set before installing and starting Orber.

Trying to change the configuration in any other way is NOT allowed since it may affect the behavior of Orber.

For more information regarding allowed values, see configuration settings in the User's Guide.

Note

Configuring the IIOP timeout values will not affect already existing connections. If you want a guaranteed uniform behavior, you must set these parameters from the start.