hwm.network.protocols.data.PipelineData Class Reference

Represents a Pipeline data connection. More...

Inheritance diagram for hwm.network.protocols.data.PipelineData:

Public Member Functions
def	__init__
	Sets up the PipelineData protocol instance. More...
def	write_output
	Sends a chunk of pipeline output to the user. More...
def	dataReceived
	Receives data that the user is trying to write to the pipeline. More...
def	connectionMade
	Sets up the data protocol before any data transfer occurs. More...
def	connectionLost
	Called when the pipeline data connection is lost.
def	perform_registrations
	Performs the necessary registrations between the protocol and its associated session. More...

Public Attributes
	session_coordinator
	session

Private Member Functions
def	_connection_setup_error
	Handles errors that arise during the data protocol connection setup. More...

Detailed Description

Represents a Pipeline data connection.

This Protocol represents a Pipeline data stream connection to the pipeline's active user (through its currently active session). It is responsible for sending the pipeline's output to the end user as well as passing the user's input to the pipeline. It uses a basic TCP protocol.

Note

This Protocol only routes the pipeline data stream (what "flows" in and out of the pipeline). All other data, such as the pipeline telemetry stream and station commands, pass through different protocols.

Constructor & Destructor Documentation

def hwm.network.protocols.data.PipelineData.__init__	(		self,
			session_coordinator
	)

Sets up the PipelineData protocol instance.

Parameters

session_coordinator

A SessionCoordinator instance that will be used to locate requested sessions.

Member Function Documentation

def hwm.network.protocols.data.PipelineData._connection_setup_error (   self,   failure  )

private

Handles errors that arise during the data protocol connection setup.

 This callback handles errors that may occur when authenticating the protocol user and loading their requested
 session. It logs the error and cleans up the protocol's connection.

Parameters

failure

A Failure object encapsulating the error.

Returns

Returns None after handling the error.

def hwm.network.protocols.data.PipelineData.connectionMade

(

self)

Sets up the data protocol before any data transfer occurs.

 This method sets up the protocol right after the connection has been established. It is responsible for calling a
 function that will wait and load the user's certificate after the TLS handshake has been performed.

Note

Because this method may be (and probably will be) called before the connection's TLS handshake is complete, it calls an additional function that periodically checks if the client's certificate is available and, once it is, returns it via a deferred. Any data that the user tries to pass to the connection before the TLS handshake has completed will be dropped.

Returns

Returns a deferred that will be fired with the requested Session.

def hwm.network.protocols.data.PipelineData.dataReceived	(		self,
			data
	)

Receives data that the user is trying to write to the pipeline.

 This method receives data from the pipeline user and passes it along to the target pipeline via the associated
 session.

Note

If the session specified in the user's SSL certificate is not yet active, any data that they send will be discarded until the session is made active active.

Parameters

data	A chunk of data of indeterminate size that is to be passed to the session.

def hwm.network.protocols.data.PipelineData.perform_registrations	(		self,
			requested_session
	)

Performs the necessary registrations between the protocol and its associated session.

 This callback makes the necessary registrations between the pipeline data protocol and its Session. It will be 
 called with session specified in the client's TLS certificate after the TLS handshake is complete.

Exceptions

May	pass along session.ProtocolAlreadyRegistered exceptions when trying to register this protocol with its session.

Parameters

requested_session

The Session associated with the protocol.

Returns

Returns the newly loaded Session that was passed to this callback.

def hwm.network.protocols.data.PipelineData.write_output	(		self,
			output_data
	)

Sends a chunk of pipeline output to the user.

 This method writes the provided chunk of data (output from the pipeline) to the end user.

Note

Because all pipeline output must reach the end user, any data received by this function is passed to the transport regardless of the buffer state. All data in the transport's buffer will eventually be sent to the pipeline user (unless the connection is lost).

See Also

https://twistedmatrix.com/documents/8.1.0/api/twisted.internet.interfaces.ITransport.html#write

Parameters

output_data

A chunk of pipeline output of arbitrary size that is to be sent to the pipeline user.

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The documentation for this class was generated from the following file:

• hwm/network/protocols/data.py