VO SAMP Hub class. More...

#include <GVOHub.hpp>

Inheritance diagram for GVOHub:

Classes
struct	client

Public Member Functions
	GVOHub (void)
	Void constructor. More...

	GVOHub (const GVOHub &hub)
	Copy constructor. More...

virtual	~GVOHub (void)
	Destructor. More...

GVOHub &	operator= (const GVOHub &hub)
	Assignment operator. More...

void	clear (void)
	Clear object. More...

GVOHub *	clone (void) const
	Clone object. More...

std::string	classname (void) const
	Return class name. More...

void	start (void)
	Start Hub. More...

std::string	print (const GChatter &chatter=NORMAL) const
	Print VO hub information. More...

Public Member Functions inherited from GBase
virtual	~GBase (void)
	Destructor. More...

Protected Member Functions
void	init_members (void)
	Initialise class members. More...

void	copy_members (const GVOHub &client)
	Copy class members. More...

void	free_members (void)
	Delete class members. More...

void	start_hub (void)
	Starts the SAMP hub socket and listens on it. More...

void	handle_request (const socklen_t &sock)
	Reads the client message and runs appropriate function. More...

void	request_ping (const socklen_t &sock)
	Handles ping requests. More...

void	request_register (const GXml &xml, const socklen_t &sock)
	Handles registration requests. More...

void	request_unregister (const GXml &xml, const socklen_t &sock)
	Handles unregistration requests. More...

void	request_declare_metadata (const GXml &xml, const socklen_t &sock)
	Handles metadata declaration requests. More...

void	request_declare_subscriptions (const GXml &xml, const socklen_t &sock)
	Handles subscriptions declaration requests. More...

void	request_set_xml_rpc_callback (const GXml &xml, const socklen_t &sock)
	Handles XML-RPC callback setting requests. More...

void	request_get_subscriptions (const GXml &xml, const socklen_t &sock)
	Handles subscriptions getting requests. More...

void	request_get_registered_clients (const GXml &xml, const socklen_t &sock)
	Handles registered client information requests. More...

void	request_get_subscribed_clients (const GXml &xml, const socklen_t &sock)
	Handles subscribed client information requests. More...

void	request_get_metadata (const GXml &xml, const socklen_t &sock)
	Handles a metadata requests. More...

void	request_notify_all (const GXml &xml, const socklen_t &sock)
	Handle request to notify all clients. More...

void	request_shutdown (const socklen_t &sock)
	Handles Hub shutdown requests. More...

std::string	get_client_key (const GXml &xml) const
	Extract client key from XML request. More...

int	get_client_index (const GXml &xml) const
	Extract client index in shared memory from XML request. More...

int	get_client_index (const std::string &reference) const
	Extract client index in shared memory from XML request. More...

std::string	get_response_value (const GXmlNode *node, const std::string &name) const
	Returns value for a named parameter. More...

std::vector< std::string >	get_subscriptions (const GXml &xml) const
	Returns subscriptions from XML document. More...

std::string	get_callback_url (const GXml &xml) const
	Returns callback URL of client. More...

std::string	get_hub_lockfile (void) const
	Returns SAMP Hub lockfile URL. More...

std::string	get_mtype (const GXml &xml) const
	Extract mtype from XML request. More...

void	create_samp_file (void) const
	Create the lockfile. More...

void	delete_samp_file (void) const
	Delete the lockfile. More...

int	get_socket (void)
	Get Hub socket. More...

void	post_samp_ok (const socklen_t &sock) const
	Post SAMP ok massage to client. More...

void	post_samp_void (const socklen_t &sock) const
	Post SAMP void massage to client. More...

void	post_string (const std::string &content, const socklen_t &sock) const
	Post string content to client. More...

void	notify (const std::string &url, const std::string &notification) const
	Send notification to client. More...

void	notify_register (const client &client, const std::string &reference)
	Notify client about another client registering at Hub. More...

void	notify_unregister (const client &client, const std::string &reference)
	Notify client about another client unregistering at Hub. More...

void	notify_metadata (const client &client, const std::string &reference)
	Notify client about the metadata of another client. More...

void	notify_image_load (const client &client, const GXml &xml)
	Notify client about image loading. More...

void	notify_table_load (const GVOHub::client &client, const GXml &xml)
	Notify client about VO table loading. More...

std::string	random_string (const size_t &length) const
	Generates random string of characters. More...

std::string	hub_url (void) const
	Return Hub URL. More...

std::string	get_client_name (const GXml &xml) const
	Return client name from XML message. More...

Protected Attributes
std::string	m_secret
	Secret Hub key. More...

std::string	m_hub_host
	Hub host. More...

std::string	m_hub_port
	Hub port. More...

std::string	m_hub_path
	Hub path. More...

std::string	m_version
	The version of the SAMP Standard Profile implemented by the hub. More...

std::string	m_hub_id
	Hub identifier used by the hub when it sends message itself rather than forwarding from others. More...

int	m_socket
	Hub socket. More...

bool	m_shutdown
	Shutdown request. More...

std::vector< client >	m_clients
	Clients. More...

Detailed Description

VO SAMP Hub class.

This class implements a SAMP hub to support the interoperability of Virtual Observatory applications.

Definition at line 51 of file GVOHub.hpp.

Constructor & Destructor Documentation

GVOHub::GVOHub ( void )

Void constructor.

Definition at line 73 of file GVOHub.cpp.

References init_members().

Referenced by clone().

GVOHub::GVOHub ( const GVOHub & hub )

Copy constructor.

Parameters

[in] hub VO Hub.

Definition at line 88 of file GVOHub.cpp.

References copy_members(), and init_members().

GVOHub::~GVOHub ( void )

virtual

Destructor.

Definition at line 104 of file GVOHub.cpp.

References free_members().

Member Function Documentation

std::string GVOHub::classname ( void ) const

inlinevirtual

Return class name.

Returns: String containing the class name ("GVOHub").

Implements GBase.

Definition at line 167 of file GVOHub.hpp.

void GVOHub::clear ( void )

virtual

Clear object.

Reset object to a clean initial state.

Implements GBase.

Definition at line 158 of file GVOHub.cpp.

References free_members(), and init_members().

GVOHub * GVOHub::clone ( void ) const

virtual

Clone object.

Implements GBase.

Definition at line 174 of file GVOHub.cpp.

References GVOHub().

void GVOHub::copy_members ( const GVOHub & hub )

protected

Copy class members.

Parameters

[in] hub VO hub.

Definition at line 260 of file GVOHub.cpp.

References m_clients, m_hub_host, m_hub_id, m_hub_path, m_hub_port, m_secret, m_shutdown, m_socket, and m_version.

Referenced by GVOHub(), and operator=().

void GVOHub::create_samp_file ( void ) const

protected

Create the lockfile.

Creates the SAMP lockfile and fill it with information. Implements IVOA standard REC-SAMP-1.3-20120411.

Definition at line 1465 of file GVOHub.cpp.

References get_hub_lockfile(), hub_url(), m_hub_id, m_secret, and m_version.

Referenced by start_hub().

void GVOHub::delete_samp_file ( void ) const

protected

Delete the lockfile.

Deletes the SAMP lockfile on disk.

Definition at line 1500 of file GVOHub.cpp.

References get_hub_lockfile().

Referenced by free_members(), and start_hub().

void GVOHub::free_members ( void )

protected

Delete class members.

Definition at line 281 of file GVOHub.cpp.

References delete_samp_file(), and m_socket.

Referenced by clear(), operator=(), and ~GVOHub().

std::string GVOHub::get_callback_url ( const GXml & xml ) const

protected

Returns callback URL of client.

Parameters

[in] xml client query XML document.

Returns: Callback URL of client.

Definition at line 1388 of file GVOHub.cpp.

References GXmlNode::append(), GXml::element(), and GXmlText::text().

Referenced by request_set_xml_rpc_callback().

int GVOHub::get_client_index ( const GXml & xml ) const

protected

Extract client index in shared memory from XML request.

Parameters

[in] xml XML message sent by client.

Returns: Client index (-1 if not found).

Extracts the client index from the XML request. The method returns -1 if no client was found.

Definition at line 1230 of file GVOHub.cpp.

References get_client_key(), and m_clients.

Referenced by request_declare_metadata(), request_declare_subscriptions(), request_get_metadata(), request_get_subscriptions(), request_set_xml_rpc_callback(), and request_unregister().

int GVOHub::get_client_index ( const std::string & reference ) const

protected

Extract client index in shared memory from XML request.

Parameters

[in] reference Client reference.

Returns: Client index (-1 if not found).

Extracts the client index from the client reference. The method returns -1 if no client was found.

Definition at line 1270 of file GVOHub.cpp.

References m_clients.

std::string GVOHub::get_client_key ( const GXml & xml ) const

protected

Extract client key from XML request.

Parameters

[in] xml XML message sent by client.

Extracts the clients key from the XML request.

Definition at line 1197 of file GVOHub.cpp.

References GXml::element(), and GXmlText::text().

Referenced by get_client_index(), request_declare_metadata(), request_declare_subscriptions(), request_get_metadata(), request_get_registered_clients(), request_get_subscriptions(), request_set_xml_rpc_callback(), and request_unregister().

std::string GVOHub::get_client_name ( const GXml & xml ) const

protected

Return client name from XML message.

Parameters

[in] xml XML message sent by client.

Returns client name from XML message.

Definition at line 2221 of file GVOHub.cpp.

References GXml::element(), and GXmlText::text().

Referenced by request_get_metadata(), and request_get_subscriptions().

std::string GVOHub::get_hub_lockfile ( void ) const

protected

Returns SAMP Hub lockfile URL.

Returns: SAMP Hub lockfile URL (empty if no lockfile was found).

Implements IVOA standard REC-SAMP-1.3-20120411.

Definition at line 1415 of file GVOHub.cpp.

References gammalib::getenv().

Referenced by create_samp_file(), and delete_samp_file().

std::string GVOHub::get_mtype ( const GXml & xml ) const

protected

Extract mtype from XML request.

Parameters

[in] xml XML message sent by client.

Extracts the mtype identifying calling message from the XML request.

Definition at line 2178 of file GVOHub.cpp.

References GXml::element(), and get_response_value().

Referenced by request_notify_all().

std::string GVOHub::get_response_value	(	const GXmlNode *	node,
		const std::string &	name
	)		const

protected

Returns value for a named parameter.

Parameters

[in]	node	XML node containing the response values.
[in]	name	Parameter name.

Returns: Parameter value.

Returns the value for the parameter name in a list of member XML nodes with the structure

<member>
  <name>name</name>
  <value>value</value>
</member>

If the specified parameter name was not found, or the the XML node is NULL, an empty string is returned.

Definition at line 1311 of file GVOHub.cpp.

References GXmlNode::element(), GXmlNode::elements(), and gammalib::xml_get_name_value_pair().

Referenced by get_mtype(), notify_image_load(), notify_table_load(), and request_declare_metadata().

int GVOHub::get_socket ( void )

protected

Get Hub socket.

Returns: Hub socket (-1 if no socket was found).

Returns Hub socket. Starting from an initial port of 2526 the method searches for the next free port and binds it to a socket.

Definition at line 1521 of file GVOHub.cpp.

References G_GET_SOCKET, m_hub_host, m_hub_port, and gammalib::str().

Referenced by start_hub().

std::vector< std::string > GVOHub::get_subscriptions ( const GXml & xml ) const

protected

Returns subscriptions from XML document.

Parameters

[in] xml client query XML document.

Returns: List of subscriptions.

Definition at line 1353 of file GVOHub.cpp.

References GXmlNode::element(), GXml::element(), GXmlNode::elements(), and GXmlText::text().

Referenced by request_declare_subscriptions().

void GVOHub::handle_request ( const socklen_t & sock )

protected

Reads the client message and runs appropriate function.

Parameters

[in] sock Socket to client.

Definition at line 366 of file GVOHub.cpp.

References GXml::element(), gammalib::recv(), request_declare_metadata(), request_declare_subscriptions(), request_get_metadata(), request_get_registered_clients(), request_get_subscribed_clients(), request_get_subscriptions(), request_notify_all(), request_ping(), request_register(), request_set_xml_rpc_callback(), request_shutdown(), request_unregister(), start(), and GXmlText::text().

Referenced by start_hub().

std::string GVOHub::hub_url ( void ) const

protected

Return Hub URL.

Returns: Hub URL.

Returns the XML-RPC endpoint for communication with the hub.

Definition at line 2204 of file GVOHub.cpp.

References m_hub_host, m_hub_path, and m_hub_port.

Referenced by create_samp_file(), print(), and request_register().

void GVOHub::init_members ( void )

protected

Initialise class members.

Definition at line 237 of file GVOHub.cpp.

References m_clients, m_hub_host, m_hub_id, m_hub_path, m_hub_port, m_secret, m_shutdown, m_socket, m_version, and random_string().

Referenced by clear(), GVOHub(), and operator=().

void GVOHub::notify	(	const std::string &	url,
		const std::string &	notification
	)		const

protected

Send notification to client.

Parameters

[in]	url	URL.
[in]	notification	Notification.

Send a notification to a url.

Definition at line 1702 of file GVOHub.cpp.

References start(), and gammalib::str().

Referenced by notify_image_load(), notify_metadata(), notify_register(), notify_table_load(), and notify_unregister().

void GVOHub::notify_image_load	(	const client &	client,
		const GXml &	xml
	)

protected

Notify client about image loading.

Parameters

[in]	client	Client.
[in]	xml	Message from which image information is extracted.

Notify a client that a FITS image is avialable for loading. The method sends a "image.load.fits" message to the client. Information about the image is extracted from the xml document.

Definition at line 2028 of file GVOHub.cpp.

References GXml::element(), get_response_value(), m_hub_id, notify(), GVOHub::client::private_key, and GVOHub::client::url.

Referenced by request_notify_all().

void GVOHub::notify_metadata	(	const client &	client,
		const std::string &	reference
	)

protected

Notify client about the metadata of another client.

Parameters

[in]	client	Client to notify.
[in]	reference	Reference of client for which metadata should be sent.

Notify a client about another the metadata of another client. The method sends a "samp.hub.event.metadata" message to the client.

Definition at line 1930 of file GVOHub.cpp.

References m_clients, m_hub_id, notify(), GVOHub::client::private_key, and GVOHub::client::url.

Referenced by request_declare_metadata().

void GVOHub::notify_register	(	const client &	client,
		const std::string &	reference
	)

protected

Notify client about another client registering at Hub.

Parameters

[in]	client	Client to notify.
[in]	reference	Reference to client which registered.

Notify a client about another client that has registered at the Hub. The method sends a "samp.hub.event.register" message to the client.

Definition at line 1834 of file GVOHub.cpp.

References m_hub_id, notify(), GVOHub::client::private_key, and GVOHub::client::url.

Referenced by request_register().

void GVOHub::notify_table_load	(	const GVOHub::client &	client,
		const GXml &	xml
	)

protected

Notify client about VO table loading.

Parameters

[in]	client	Client.
[in]	xml	Message from which table information is extracted.

Notify a client that a VO table is avialable for loading. The method sends sends a "table.load.votable" message to the client. Information about the VO table is extracted from the xml document.

Definition at line 2094 of file GVOHub.cpp.

References GXml::element(), get_response_value(), m_hub_id, notify(), GVOHub::client::private_key, and GVOHub::client::url.

Referenced by request_notify_all().

void GVOHub::notify_unregister	(	const client &	client,
		const std::string &	reference
	)

protected

Notify client about another client unregistering at Hub.

Parameters

[in]	client	Client to notify.
[in]	reference	Reference to client who unregistered.

Notify a client about another client that has unregistered at the Hub. The method sends a "samp.hub.event.unregister" message to the client.

Definition at line 1882 of file GVOHub.cpp.

References m_hub_id, notify(), GVOHub::client::private_key, and GVOHub::client::url.

Referenced by request_unregister().

GVOHub & GVOHub::operator= ( const GVOHub & hub )

Assignment operator.

Parameters

[in] hub VO hub.

Returns: VO hub.

Definition at line 126 of file GVOHub.cpp.

References copy_members(), free_members(), and init_members().

void GVOHub::post_samp_ok ( const socklen_t & sock ) const

protected

Post SAMP ok massage to client.

Parameters

[in] sock Socket.

Posts a SAMP OK message to a client.

Definition at line 1637 of file GVOHub.cpp.

References post_string().

Referenced by request_declare_subscriptions(), request_set_xml_rpc_callback(), and request_shutdown().

void GVOHub::post_samp_void ( const socklen_t & sock ) const

protected

Post SAMP void massage to client.

Parameters

[in] sock Socket.

Posts a void SAMP message to a client. Void messages can typically be discared by the client.

Definition at line 1671 of file GVOHub.cpp.

References post_string().

Referenced by request_declare_metadata(), request_notify_all(), request_ping(), and request_unregister().

void GVOHub::post_string	(	const std::string &	content,
		const socklen_t &	sock
	)		const

protected

Post string content to client.

Parameters

[in]	content	String content to post.
[in]	sock	Socket.

Posts the content of a string to a client.

Definition at line 1584 of file GVOHub.cpp.

References gammalib::str().

Referenced by post_samp_ok(), post_samp_void(), request_get_metadata(), request_get_registered_clients(), request_get_subscribed_clients(), request_get_subscriptions(), and request_register().

std::string GVOHub::print ( const GChatter & chatter = NORMAL ) const

virtual

Print VO hub information.

Parameters

[in] chatter Chattiness (defaults to NORMAL).

Returns: String containing VO hub information

Implements GBase.

Definition at line 200 of file GVOHub.cpp.

References hub_url(), m_hub_host, m_hub_id, m_hub_path, m_hub_port, m_secret, m_version, gammalib::parformat(), and SILENT.

std::string GVOHub::random_string ( const size_t & length ) const

protected

Generates random string of characters.

Parameters

[in] length Length of random string

Definition at line 2156 of file GVOHub.cpp.

References gammalib::str().

Referenced by init_members(), and request_register().

void GVOHub::request_declare_metadata	(	const GXml &	xml,
		const socklen_t &	sock
	)

protected

Handles metadata declaration requests.

Parameters

[in]	xml	XML message sent by client.
[in]	sock	Socket.

Handles all incoming metadata declaration requests.

Definition at line 654 of file GVOHub.cpp.

References GXml::element(), get_client_index(), get_client_key(), get_response_value(), m_clients, notify_metadata(), and post_samp_void().

Referenced by handle_request().

void GVOHub::request_declare_subscriptions	(	const GXml &	xml,
		const socklen_t &	sock
	)

protected

Handles subscriptions declaration requests.

Parameters

[in]	xml	XML message sent by client.
[in]	sock	Socket.

Handles all incoming subscription declaration requests.

Definition at line 718 of file GVOHub.cpp.

References get_client_index(), get_client_key(), get_subscriptions(), m_clients, and post_samp_ok().

Referenced by handle_request().

void GVOHub::request_get_metadata	(	const GXml &	xml,
		const socklen_t &	sock
	)

protected

Handles a metadata requests.

Parameters

[in]	xml	XML message sent by client.
[in]	sock	Socket.

Handles all metadata requests.

Definition at line 979 of file GVOHub.cpp.

References get_client_index(), get_client_key(), get_client_name(), m_clients, and post_string().

Referenced by handle_request().

void GVOHub::request_get_registered_clients	(	const GXml &	xml,
		const socklen_t &	sock
	)

protected

Handles registered client information requests.

Parameters

[in]	xml	XML message sent by client.
[in]	sock	Socket.

Handles all incoming registered client information requests.

Definition at line 887 of file GVOHub.cpp.

References get_client_key(), m_clients, and post_string().

Referenced by handle_request().

void GVOHub::request_get_subscribed_clients	(	const GXml &	xml,
		const socklen_t &	sock
	)

protected

Handles subscribed client information requests.

Parameters

[in]	xml	XML message sent by client.
[in]	sock	Socket.

Handles all incoming subscribed client information requests.

Definition at line 937 of file GVOHub.cpp.

References post_string().

Referenced by handle_request().

void GVOHub::request_get_subscriptions	(	const GXml &	xml,
		const socklen_t &	sock
	)

protected

Handles subscriptions getting requests.

Parameters

[in]	xml	XML message sent by client.
[in]	sock	Socket.

Handles all incoming subscriptions getting requests.

Definition at line 810 of file GVOHub.cpp.

References get_client_index(), get_client_key(), get_client_name(), m_clients, and post_string().

Referenced by handle_request().

void GVOHub::request_notify_all	(	const GXml &	xml,
		const socklen_t &	sock
	)

protected

Handle request to notify all clients.

Parameters

[in]	xml	XML message sent by client.
[in]	sock	Socket.

Handles requests to notify all clients. The method will loop over all clients to check the subscriptions of each client, and send a notification to all clients that are subscribed to the requested message type.

Definition at line 1117 of file GVOHub.cpp.

References get_mtype(), m_clients, notify_image_load(), notify_table_load(), and post_samp_void().

Referenced by handle_request().

void GVOHub::request_ping ( const socklen_t & sock )

protected

Handles ping requests.

Parameters

[in] sock Socket.

Handles all incoming ping requests.

Definition at line 487 of file GVOHub.cpp.

References post_samp_void().

Referenced by handle_request().