TelnetClient::TelnetClient Class Reference

The TelnetClient class allows communication with a telnet server; it can be used directly or subclassed with overridden methods to customize its behavior. More...

Public Member Methods
	clearStats ()
	Clears performance statistics. More...
nothing	clearWarningQueue ()
	Removes any warning Queue object from the Socket. More...
	connect (timeout timeout=DefaultConnTimeout)
	connects to the Telnet server More...
	constructor (string connect, *code log, *code dbglog)
	creates the TelnetClient object from a target string and optional log closure(s) More...
	constructor (string host, softint port, *code log, *code dbglog)
	creates the TelnetClient object More...
	destructor ()
	disconnects from the server if connected and deletes the object
	disconnect ()
	disconnects from the Telnet server More...
*string	getAvailableData (timeout t=DefaultTimeout)
	returns all data available as a string (which could be an empty string if no data is available in the timeout period) or NOTHING if the connection was closed by the remote end More...
string	getTarget ()
	Returns the connection target string. More...
hash< auto >	getUsageInfo ()
	Returns performance statistics for the socket. More...
*string	getUser ()
	returns the current value of the username parameter
bool	hasFeature (int fc)
	returns True if the server has confirmed with a DO command that it supports the given feature More...
bool	isConnected ()
	returns True if the client is connected to the server
	sendData (softlist arr)
	sends data to the server More...
	sendTextData (string str)
	sends literal string data to the server; the text dat is converted to the socket's encoding if necessary More...
	setEventQueue ()
	Removes any Queue object so that socket events are no longer added to the Queue. More...
	setEventQueue (Qore::Thread::Queue queue, auto arg, *bool with_data)
	Sets a Queue object to receive socket events. More...
	setUser (*string n_user)
	sets or clears (in case passed with no value) the username parameter for logging in to the telnet server More...
nothing	setWarningQueue (int warning_ms, int warning_bs, Queue queue, any arg, timeout min_ms=1s)
	Sets a Queue object to receive socket warnings. More...
	windowSizeUpdated ()
	this method should be called externally when the window size has changed More...

Private Member Methods
*string	getDisplay ()
	this method provides the value that will be given as the DISPLAY value in protocol negotiation More...
hash	getEnvironment ()
	this method provides the value that will be given as the user's environment in protocol negotiation More...
int	getTerminalSpeed ()
	this method provides the value that will be given as the terminal speed in protocol negotiation More...
*string	getTerminalType ()
	this method provides the value that will be given as the terminal type in protocol negotiation More...
hash	getWindowSize ()
	this method provides the value that will be given as the terminal window size in protocol negotiation More...
	log (string msg)
	logs the message to the log closure set with the constructor (if any)
	logDbg (string msg)
	logs the message to the debug log closure set with the constructor (if any)

Detailed Description

The TelnetClient class allows communication with a telnet server; it can be used directly or subclassed with overridden methods to customize its behavior.

This class uses a Mutex lock in each TelnetClient object to ensure thread serialization to the underlying socket and its internal configuration, so it is safe to access in a multithreaded context.

Member Function Documentation

clearStats()

TelnetClient::TelnetClient::clearStats

(

)

Clears performance statistics.

Example:

telnet.clearStats();

Since

TelnetClient 1.1

See also

TelnetClient::getUsageInfo()

clearWarningQueue()

nothing TelnetClient::TelnetClient::clearWarningQueue

(

)

Removes any warning Queue object from the Socket.

Example:

telnet.clearWarningQueue();

See also

setWarningQueue()

Since

TelnetClient 1.1

connect()

TelnetClient::TelnetClient::connect

(

timeout

timeout = DefaultConnTimeout

)

connects to the Telnet server

If the object is already connected, it is disconnected and a new connection attempt is made.

Note

This method is subject to thread serialization.

constructor() [1/2]

TelnetClient::TelnetClient::constructor	(	string	connect,
		*code	log,
		*code	dbglog
	)

creates the TelnetClient object from a target string and optional log closure(s)

Parameters

connect	the hostname of the Telnet server or a hostname:port specification (use [hostname] or [address] for ipv6 connections); also accepts URLs with a scheme "telnet://", any other scheme, or of the URL contains a username, password, or path, an INVALID-TARGET exception will be thrown
log	a closure or call reference for log messages; a single string argument will be passed to this code for logging
dbglog	a closure or call reference for debugging/technical log messages; a single string argument will be passed to this code for logging

Note

a UNIX domain socket target can be given with a URL in the following format: scheme://socket=url_encoded_path/path, where url_encoded_path is a path with URL-encoding as performed by encode_url(string, True); for example: "telnet://socket=%2ftmp%socket-dir%2fsocket-file-1"; this allows a filesystem path to be used in the host portion of the URL providing the path to the UNIX domain socket.

Exceptions

INVALID-TARGET

the connection argument contains a URL with an invalid target scheme or unsupported components (username, password, or path)

constructor() [2/2]

TelnetClient::TelnetClient::constructor	(	string	host,
		softint	port,
		*code	log,
		*code	dbglog
	)

creates the TelnetClient object

Parameters

host	the hostname of the telnet server (use [hostname] to explicitly specify an ipv6 connection)
port	the port number of the telnet server
log	a closure or call reference for log messages; a single string argument will be passed to this code for logging
dbglog	a closure for debugging/technical log messages; a single string argument will be passed to this code for logging

disconnect()

TelnetClient::TelnetClient::disconnect

(

)

disconnects from the Telnet server

Note

This method is subject to thread serialization.

getAvailableData()

*string TelnetClient::TelnetClient::getAvailableData

(

timeout

t = DefaultTimeout

)

returns all data available as a string (which could be an empty string if no data is available in the timeout period) or NOTHING if the connection was closed by the remote end

NOTHING is only returned if the remote end closed the connection

Note

• This method could throw any exception that Socket::recvu1() could throw except SOCKET-CLOSED (in which case the exception is caught and NOTHING is returned)
• This method is subject to thread serialization

getDisplay()

*string TelnetClient::TelnetClient::getDisplay ( )

private

this method provides the value that will be given as the DISPLAY value in protocol negotiation

override this method in a subclass to provide a different value

getEnvironment()

hash TelnetClient::TelnetClient::getEnvironment ( )

private

this method provides the value that will be given as the user's environment in protocol negotiation

override this method in a subclass to provide a different value

getTarget()

string TelnetClient::TelnetClient::getTarget

(

)

Returns the connection target string.

Since

TelnetClient 1.3

getTerminalSpeed()

int TelnetClient::TelnetClient::getTerminalSpeed ( )

private

this method provides the value that will be given as the terminal speed in protocol negotiation

override this method in a subclass to provide a different value

getTerminalType()

*string TelnetClient::TelnetClient::getTerminalType ( )

private

this method provides the value that will be given as the terminal type in protocol negotiation

override this method in a subclass to provide a different value

getUsageInfo()

hash<auto> TelnetClient::TelnetClient::getUsageInfo

(

)

Returns performance statistics for the socket.

Example:

hash<auto> h = telnet.getUsageInfo();

Returns

a hash with the following keys:

• "bytes_sent": an integer giving the total amount of bytes sent
• "bytes_recv": an integer giving the total amount of bytes received
• "us_sent": an integer giving the total number of microseconds spent sending data
• "us_recv": an integer giving the total number of microseconds spent receiving data
• "arg": (only if warning values have been set with TelnetClient::setWarningQueue()) the optional argument for warning hashes
• "timeout": (only if warning values have been set with TelnetClient::setWarningQueue()) the warning timeout in microseconds
• "min_throughput": (only if warning values have been set with TelnetClient::setWarningQueue()) the minimum warning throughput in bytes/sec

Since

TelnetClient 1.1

See also

TelnetClient::clearStats()

getWindowSize()

hash TelnetClient::TelnetClient::getWindowSize ( )

private

this method provides the value that will be given as the terminal window size in protocol negotiation

The default implementation of this method is to return the actual terminal size by calling TermIOS::getWindowSize(). Override this method in a subclass to provide a different value.

Returns

a hash with the following keys:

• rows: the number of rows in the display
• columns: the number of columns in the display

hasFeature()

bool TelnetClient::TelnetClient::hasFeature

(

int

fc

)

returns True if the server has confirmed with a DO command that it supports the given feature

Parameters

fc	The feature code to check; see Telnet Command Option Codes for possible values; supported features are: TOPT_TS: TerminalSpeed TOPT_XDL: XDisplayLocation TOPT_TERM: TerminalType TOPT_ENVIR_NEW: TelnetNewEnvironmentOption TOPT_SUPP: SuppressGoAhead TOPT_NAWS: NegotiateAboutWindowSize

sendData()

TelnetClient::TelnetClient::sendData

(

softlist

arr

)

sends data to the server

Parameters

arr

a single element or a list of elements to send to the server; elements can be as follows: string: currently sent verbatim to the server, in particular no encoding conversions are performed on this string (possibly these should be scanned for IAC characters which should be duplicated) integer: treated as a single-byte value; if the value is IAC (ie 255 or 0xff) then it is sent twice binary: sent verbatim to the server

Exceptions

SEND-ERROR	this exception is thrown if an invalid data type is passed to this method
NOT-CONNECTED-EXCEPTION	if the socket is not already connected then this exception is thrown

Note

• This method could also throw any exception that Socket::sendBinary2() or Socket::sendi1() could throw
• This method is subject to thread serialization

sendTextData()

TelnetClient::TelnetClient::sendTextData

(

string

str

)

sends literal string data to the server; the text dat is converted to the socket's encoding if necessary

Parameters

str	currently sent verbatim to the server; no encoding conversions are performed on this string (possibly these should be scanned for IAC characters which should be duplicated)

Exceptions

NOT-CONNECTED-EXCEPTION

if the socket is not already connected then this exception is thrown

Note

• This method could also throw any exception that Socket::sendBinary2() could throw
• This method is subject to thread serialization

setEventQueue() [1/2]

TelnetClient::TelnetClient::setEventQueue

(

)

Removes any Queue object so that socket events are no longer added to the Queue.

Example:

telnet.setEventQueue();

See also

I/O Event Handling for more information

Since

TelnetClient 1.6

setEventQueue() [2/2]

TelnetClient::TelnetClient::setEventQueue	(	Qore::Thread::Queue	queue,
		auto	arg,
		*bool	with_data
	)

Sets a Queue object to receive socket events.

Example:

telnet.setEventQueue(queue);

Parameters

queue	the Queue object to receive socket events; note that the Queue passed cannot have any maximum size set or a QUEUE-ERROR will be thrown
arg	an argument that will be included in each event hash in the arg key
with_data	if True, then the actual raw data transferred / received is also included in the events

Exceptions

QUEUE-ERROR

the Queue passed has a maximum size set

See also

I/O Event Handling for more information

Since

TelnetClient 1.6

setUser()

TelnetClient::TelnetClient::setUser

(

*string

n_user

)

sets or clears (in case passed with no value) the username parameter for logging in to the telnet server

Parameters

n_user

the username to use for logins

Note

This method is subject to thread serialization.

setWarningQueue()

nothing TelnetClient::TelnetClient::setWarningQueue	(	int	warning_ms,
		int	warning_bs,
		Queue	queue,
		any	arg,
		timeout	min_ms = 1s
	)

Sets a Queue object to receive socket warnings.

Example:

telnet.setWarningQueue(5000, 5000, queue, "socket-1");

Parameters

warning_ms	the threshold in milliseconds for individual socket actions (send, receive, connect), if exceeded, a socket warning is placed on the warning queue with the following keys: "type": a string with the constant value "SOCKET-OPERATION-WARNING" "operation": a string giving the operation that caused the warning (ex: "connect") "us": an integer giving the number of microseconds for the operation "timeout": an integer giving the warning threshold in microseconds "arg": if any "arg" argument is passed to the TelnetClient::setWarningQueue() method, it will be included in the warning hash here
warning_bs	value in bytes per second; if any call has performance below this threshold, a socket warning is placed on the warning queue with the following keys: "type": a string with the constant value "SOCKET-THROUGHPUT-WARNING" "dir": either "send" or "recv" depending on the direction of the data flow "bytes": the amount of bytes sent "us": an integer giving the number of microseconds for the operation "bytes_sec": a float giving the transfer speed in bytes per second "threshold": an integer giving the warning threshold in bytes per second "arg": if any "arg" argument is passed to the TelnetClient::setWarningQueue() method, it will be included in the warning hash here
queue	the Queue object to receive warning events
arg	an optional argument to be placed in the "arg" key in each warning hash (could be used to identify the socket for example)
min_ms	the minimum transfer time with a resolution of milliseconds for a transfer to be eligible for triggering a warning; transfers that take less than this period of time are not eligible for raising a warning

Exceptions

QUEUE-ERROR	the Queue passed has a maximum size set
SOCKET-SETWARNINGQUEUE-ERROR	at least one of warning_ms and warning_bs must be > 0

See also

TelnetClient::clearWarningQueue()

Since

TelnetClient 1.1

windowSizeUpdated()

TelnetClient::TelnetClient::windowSizeUpdated

(

)

this method should be called externally when the window size has changed

See also

getWindowSize()