OMQ::AbstractParallelStream Class Reference

common base class for streams using a background thread for socket I/O More...

Inheritance diagram for OMQ::AbstractParallelStream:

Public Member Methods
	destructor ()
	wait for any I/O in progress to complete
nothing	cleanupBase ()
	called by child classes when the thread resource is still allocated and the thread exits or one of Qore::throw_thread_resource_exceptions() or Qore::throw_thread_resource_exceptions_to_mark() is called
private	waitIoComplete ()
	waits for the I/O thread to complete and returns
private	markIoInProgress ()
	marks the current connection as in progress; must be already checked beforehand that it's not in progress
private	markIoComplete ()
	performs thread cleanup on the background I/O thread if any is registered and running
OMQ::StreamInfo	getInfo ()
	returns performance information about the stream
private	checkError (string cmd)
	checks for an error in the background send thread; if there is one, then rethrows the exception in the main application / data thread
private	startStream ()
	opens the remote transaction by calling startStreamImpl() and starts the background I/O socket thread More...
private	socketThread (*ThreadLocalData my_tld)
	sets up thread-local data if possible and calls socketThreadImpl() that implements the background socket I/O for the object
private	abortIo (string reason)
	signals the end of queue operations
private bool	abortIoWait (string reason)
	signals the end of queue operations and waits until the socket thread terminates More...
private	beginTransaction (OMQ::DbStreamConfig m_config)
	starts or continues a remote transaction
private	commit (OMQ::DbStreamConfig m_config)
	commits a remote transaction
private	rollback (OMQ::DbStreamConfig m_config)
	rolls back a remote transaction
abstract OMQ::StreamConfig	config ()
	returns the configuration object

Static Public Member Methods
static	staticCleanup ()
	performs static thread resource cleanup on I/O thread resources
static	checkStream (QorusSystemRestHelper helper, string op)
	checks if there is a stream operation running in the background, if so, a user-friendly exception is thrown
static	beginTransaction (QorusSystemRestHelper remote, string datasource, *timeout timeout_ms, *reference info)
	starts a transaction in a remote datasource More...

Public Attributes
const	DO_DISCONNECT = True
	A constant for rollback() methods to perform real disconnect.
const	DONT_DISCONNECT = False
	A constant for rollback() methods to keep the network connection alive.

Private Member Methods
Qore::Thread::Counter	cnt ()
	confirmation counter for the socket I/O thread
OMQ::StreamInfo	m_info ()
	stream information
abstract	socketThreadImpl ()
	this method implements the background thread that handles the actual DataStream socket sends
abstract	startStreamImpl ()
	opens the remote transaction before starting the background I/O socket thread

Private Attributes
Qore::Thread::Queue	dataq
	Queue for the socket I/O thread.
*hash	thread_ex
	exception info for send thread to communicate errors to the primary data thread
string	objid
	stream object identifier
const	StreamTerminatedError = "STREAM-TERMINATED"
	stream terminated error
const	ThreadKey = "_STREAM_"
	thread-local data key

Detailed Description

common base class for streams using a background thread for socket I/O

Member Function Documentation

abortIoWait()

private bool OMQ::AbstractParallelStream::abortIoWait

(

string

reason

)

signals the end of queue operations and waits until the socket thread terminates

Parameters

reason

the reason for aborting the I/O thread

Returns

True if there was I/O still in progress, False if not

beginTransaction()

static OMQ::AbstractParallelStream::beginTransaction ( QorusSystemRestHelper  remote, string  datasource, *timeout  timeout_ms, *reference  info  )

static

starts a transaction in a remote datasource

Example:

AbstractParallelStream::beginTransaction(remote, dsname);

Parameters

remote	a OMQ::QorusSystemRestHelper object
datasource	the name of the datasource in the remote server
timeout_ms	an optional timeout value in milliseconds for HTTP communication
info	an optional reference to an lvalue that will be used as an output variable giving a hash of request headers and other information about the HTTP request

The "Qorus-Connection: Continue-Persistent" header is sent with the call so that a new transaction is started or any transaction in progress is continued

startStream()

private OMQ::AbstractParallelStream::startStream

(

)

opens the remote transaction by calling startStreamImpl() and starts the background I/O socket thread

Exceptions

STREAM-ERROR

if the same remote connection object is already active with a remote stream, this exception is thrown

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

• Streams.qc