DbRecordRetrievalEngine Class Reference

Network-connection logic relating fetching db records from DHT. More...

#include <dbretrievalengine.h>

Inheritance diagram for DbRecordRetrievalEngine:

Collaboration diagram for DbRecordRetrievalEngine:

Classes
struct	DlQueueItemStruct

Public Slots
void	stopRetrieving ()
void	notifyOfContentReceived (const Hash &aHashOfContent, const ProtocolItemType aTypeOfReceivedContent)
void	nodeConnectionAttemptStatus (Connection::ConnectionState aStatus, const Hash aHashOfAttemptedNode)
void	run ()

Public Member Functions
	DbRecordRetrievalEngine (Controller *aController, Model &aModel)
	~DbRecordRetrievalEngine ()
void	startRetrieving (CaDbRecord::SearchTerms aSearchTerms)

Private Types
typedef struct DbRecordRetrievalEngine::DlQueueItemStruct	DlQueueItem

Private Member Functions
void	sendQueryToNode (const CaDbRecord::SearchTerms &aSearchTerms, const Hash &aNodeFingerPrint)

Private Attributes
Controller *	iController
Model &	iModel
bool	iNowRunning
QList< Hash >	iNodeCandidatesToTryQuery
QList< Hash >	iNodesSuccessfullyConnected
QList< Hash >	iNodesFailurefullyConnected
QList< DlQueueItem >	iSearchTerms

Detailed Description

Network-connection logic relating fetching db records from DHT.

Special retrieval logic for records of distributed db records only. See also RetrievalEngine that is used to fetch classified ads or binary files. RetrievalEngine is limited to fetching one item at time, with db records we may have multiple collections open at the same time and it may be necessary to fetch from all of those, and at the same time honouring possible search terms that user may have given.

Method is called via controller due to users activity usually inside TCL program. If conditions are met, this class locates nodes in the network that store the desired collection and repeates the query to those nodes in hope to retrieve more records matching the query.

Member Typedef Documentation

DlQueueItem

typedef struct DbRecordRetrievalEngine::DlQueueItemStruct DbRecordRetrievalEngine::DlQueueItem

private

Type definition for download queue items. See iSearchTerms

Constructor & Destructor Documentation

DbRecordRetrievalEngine()

DbRecordRetrievalEngine::DbRecordRetrievalEngine	(	Controller *	aController,
		Model &	aModel
	)

Constructor

Parameters

aController	application controller. not owned.
aModel	persistent storage.

~DbRecordRetrievalEngine()

DbRecordRetrievalEngine::~DbRecordRetrievalEngine

(

)

Destructor

Member Function Documentation

nodeConnectionAttemptStatus

void DbRecordRetrievalEngine::nodeConnectionAttemptStatus ( Connection::ConnectionState  aStatus, const Hash  aHashOfAttemptedNode  )

slot

when connection is attempted, NetworkListener will emit the status (failed or success) of the connection, emitted signal is connected here

notifyOfContentReceived

void DbRecordRetrievalEngine::notifyOfContentReceived ( const Hash &  aHashOfContent, const ProtocolItemType  aTypeOfReceivedContent  )

slot

when content is received, we may want to check if it was the content we were waiting for. this method is for performing that check

run

void DbRecordRetrievalEngine::run ( )

slot

this class is a not a thread, but QTimer, thus run.

sendQueryToNode()

void DbRecordRetrievalEngine::sendQueryToNode ( const CaDbRecord::SearchTerms &  aSearchTerms, const Hash &  aNodeFingerPrint  )

private

startRetrieving()

void DbRecordRetrievalEngine::startRetrieving

(

CaDbRecord::SearchTerms

aSearchTerms

)

command-interface for this class: start to do work

Parameters

aSearchTerms

specifies the database records to dl.

stopRetrieving

void DbRecordRetrievalEngine::stopRetrieving ( )

slot

Command-interface for this class: cancel all ongoing retrievals. This gets connected to "finished" signal of the tcl interpreter: when program stops, it makes no more sense to serve it with db requests.

Member Data Documentation

iController

Controller* DbRecordRetrievalEngine::iController

private

application controller

iModel

Model& DbRecordRetrievalEngine::iModel

private

persistent storage

iNodeCandidatesToTryQuery

QList<Hash> DbRecordRetrievalEngine::iNodeCandidatesToTryQuery

private

iNodesFailurefullyConnected

QList<Hash> DbRecordRetrievalEngine::iNodesFailurefullyConnected

private

iNodesSuccessfullyConnected

QList<Hash> DbRecordRetrievalEngine::iNodesSuccessfullyConnected

private

iNowRunning

bool DbRecordRetrievalEngine::iNowRunning

private

iSearchTerms

QList<DlQueueItem> DbRecordRetrievalEngine::iSearchTerms

private

List of records to try retrieve. In pair inside the list the "first" item is actual search condidtions, second is list of node fingerprints that have already received the search query ; so it won't be sent again

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

• dbretrievalengine.h