TRODBSessionManager

Overview

TRODBSessionManager implements a sophisticated session manager that stores session data in a database accessed by standard Delphi data access components. This database can in theory be shared by multiple servers, allowing session state to be accessible across a server farm.

DB script

CREATE TABLE [dbo].[Sessions] (
    [SessionID] [char] (38) COLLATE SQL_Latin1_General_CP1_CI_AS NOT NULL ,
    [Created] [datetime] NULL ,
    [LastAccessed] [datetime] NULL ,
    [Data] [IMAGE] NULL
)
GO

ALTER TABLE [dbo].[Sessions] WITH NOCHECK ADD
    CONSTRAINT [PK_Sessions] PRIMARY KEY  CLUSTERED
    (
        [SessionID]
    )  ON [PRIMARY]
GO

Required Datasets/Commands:

Name SQL
ClearSessionsDataset DELETE FROM Sessions WHERE LastAccessed < :LastAccessed
DeleteDataset DELETE FROM Sessions WHERE SessionID = :SessionID
GetCountDataset SELECT COUNT(*) FROM Sessions
InsertDataset INSERT INTO Sessions (SessionID, Created, LastAccessed, Data) VALUES ( :SessionID, :Created, :LastAccessed, :Data)
SelectAllDataset SELECT * FROM Sessions
SelectDataset SELECT * FROM Sessions WHERE SessionID = :SessionID
UpdateDataset UPDATE Sessions SET LastAccessed = :LastAccessed, Data = :Data WHERE SessionID = :SessionID

Location


 

constructor Create  override

Standard component constructor

constructor Create(aOwner: TComponent)

Parameters:

  • aOwner: Owner

Assign  override

Copies the contents of another, similar object.

procedure Assign(Source: TPersistent)

Parameters:

  • Source: Instance whose properties will be copied

AutoTransaction

Controls of using implicit (True) or explicit (False) database transactions.

property AutoTransaction: Boolean read write

CheckProperties  override

Validates the session manager properties.

procedure CheckProperties

CheckSessionIsExpired (TROSession): Boolean  overload    (declared in TROCustomSessionManager)

Checks state of given session.

function CheckSessionIsExpired(aSession: TROSession): Boolean

Parameters:

  • aSession: Given session.

CheckSessionIsExpired (TGUID): Boolean  overload    (declared in TROCustomSessionManager)

Checks state of given session or not.

function CheckSessionIsExpired(const aSessionID: TGUID): Boolean

Parameters:

  • aSessionID: Session ID

Clearing  protected    (declared in TROCustomSessionManager)

internal flag that is set when session are clearing

property Clearing: Boolean read

ClearSessions    (declared in TROCustomSessionManager)

Discards all sessions within the session manager, so that any new call from a client will start with a fresh session.

procedure ClearSessions(OnlyExpired: Boolean)

Parameters:

  • OnlyExpired: process only expired sessions or not.

ClearSessionsDataset

This TDataset component will be used to DELETE all sessions from the database, when ClearSessions is called or if the ClearSessionsOnCreate or ClearSessionsOnDestroy properties are set to true.

property ClearSessionsDataset: TDataset read write

ClearSessionsOnCreate

Forces the session manager to clear the database of old sessions when the component is created (i.e. usually at application startup).

property ClearSessionsOnCreate: Boolean read write

ClearSessionsOnDestroy

Determines whether the session manager should clear the database of old sessions when the component is destroyed (i.e. usually at application shutdown).

property ClearSessionsOnDestroy: Boolean read write

CreateSession    (declared in TROCustomSessionManager)

Creates a new session with provided ID.

function CreateSession(const aSessionID: TGUID): TROSession

Parameters:

  • aSessionID: Session ID

CreateTimerByRequest  protected    (declared in TROCustomSessionManager)

Creates internal timer.

procedure CreateTimerByRequest

DeleteDataset

This TDataset component will be used to DELETE sessions from the database, when they expire or are explicitly deleted.

property DeleteDataset: TDataset read write

DeleteSession    (declared in TROCustomSessionManager)

Deletes the session with specified ID.

procedure DeleteSession(const aSessionID: TGUID; IsExpired: Boolean)

Parameters:

  • aSessionID: Session ID
  • IsExpired: current state of session

DeleteTemporarySession    (declared in TROCustomSessionManager)

Deletes the temporary session.

procedure DeleteTemporarySession(var Session: TROSession)

Parameters:

  • Session: given session.

DoClearSessions  protected override

Discards all sessions within the session manager, so that any new call from a client will start with a fresh session.

procedure DoClearSessions(OnlyExpired: Boolean)

Parameters:

  • OnlyExpired: process only expired sessions or not.

DoConvertGUID  protected virtual

Calls to OnConvertGUID (if set) or uses GUIDToString for getting a text representation of given aGUID.

function DoConvertGUID(const aGUID: TGUID): string

Parameters:

  • aGUID: guid

DoCreateSession  protected virtual    (declared in TROCustomSessionManager)

Creates a new session with provided ID.

function DoCreateSession(const aSessionID: TGUID): TROSession

Parameters:

  • aSessionID: Session ID

DoDeleteSession  protected override

Deletes the session with specified ID.

procedure DoDeleteSession(const aSessionID: TGUID; IsExpired: Boolean)

Parameters:

  • aSessionID: Session ID
  • IsExpired: current state of session

DoFindSession  protected override

Finds session with the specified GUID

function DoFindSession(const aSessionID: TGUID; aUpdateTime: Boolean): TROSession

Parameters:

  • aSessionID: Session ID.
  • aUpdateTime: Update LastAccess of found session or not

DoGetAllSessions  protected override

Returns a string list containing the IDs of all currently active sessions.

procedure DoGetAllSessions(Dest: TStringList)

Parameters:

  • Dest: destination

DoGetSessionCount  protected override

Returns the session count.

function DoGetSessionCount: Integer

DoNotifySessionsChangesListener  protected virtual    (declared in TROCustomSessionManager)

Notifies attached listeners about changes

procedure DoNotifySessionsChangesListener(const aSessionID: TGUID; aSessionAction: TROSessionsActions; Sender: TObject)

Parameters:

  • aSessionID: Session ID
  • aSessionAction: action
  • Sender: sender

DoReleaseSession  protected override

Releases the previously acquired session.

procedure DoReleaseSession(aSession: TROSession; NewSession: Boolean)

Parameters:

  • aSession: given session
  • NewSession: newly created session or not

DoTimerTick  protected virtual    (declared in TROCustomSessionManager)

Clears expired sessions.

procedure DoTimerTick(CurrentTickCount: Cardinal)

Parameters:

  • CurrentTickCount: ignored

FieldNameCreated

Sets the database field used to store the time and date the session was originally created.

property FieldNameCreated: string read write

FieldNameData

Defines the database field used to store the session data. This must be a BLOB field.

property FieldNameData: string read write

FieldNameLastAccessed

Sets the database field used to store the time and date the session was last accessed.

property FieldNameLastAccessed: string read write

FieldNameSessionID

Determines the database field used to store the session ID. This must be a GUID field, or a string field of 38 characters.

property FieldNameSessionID: string read write

FindSession    (declared in TROCustomSessionManager)

Finds session with the specified GUID

function FindSession(const aSessionID: TGUID; aUpdateTime: Boolean): TROSession

Parameters:

  • aSessionID: Session ID.
  • aUpdateTime: Update LastAccess of found session or not

GetAllSessions  overload    (declared in TROCustomSessionManager)

function GetAllSessions: TROSessionIDs

GetAllSessions (TStringList)  overload    (declared in TROCustomSessionManager)

Returns a string list containing the IDs of all currently active sessions. Depending on the session manager and on your application architecture, this list can be huge, especially when using a database based session list that is shared by a large server farm. Obtaining the full list of sessions can be a costly process.

procedure GetAllSessions(Dest: TStringList)

Parameters:

  • Dest: destination

GetCountDataset

This TDataset component will be used to get the number of sessions contained in the database.

property GetCountDataset: TDataset read write

GetSessionCount    (declared in TROCustomSessionManager)

Returns the session count.

function GetSessionCount: Integer

InsertDataset

Defines the TDataset component that will be used to INSERT new sessions into the database, when they are first created.

property InsertDataset: TDataset read write

IsSessionPresent    (declared in TROCustomSessionManager)

function IsSessionPresent(const aSessionID: TGUID): Boolean

Parameters:

  • aSessionID:

KillTimer  protected    (declared in TROCustomSessionManager)

Kills internal timer

procedure KillTimer

LockForReading  protected    (declared in TROCustomSessionManager)

procedure LockForReading

LockForWriting  protected    (declared in TROCustomSessionManager)

procedure LockForWriting

MaxSessions    (declared in TROCustomSessionManager)

Specifies the maximum number of sessions that will be allowed. -1 (the default) indicates that no limit on number of sessions will be enforced. Allowing a server to run without enforcing any limit on the number of sessions might pose a security risk, as malicious clients could theoretically start an infinite number of sessions by performing repeated requests with changing Client IDs, until server memory is depleted. You should make sure to either set a limit, or tie session creation to user authentication, so that only valid client users can obtain a session(and possibly only one session per login).

property MaxSessions: Integer read write

Notification  protected override

Forwards notification messages to all owned components.

procedure Notification(AComponent: TComponent; Operation: TOperation)

Parameters:

  • AComponent: component
  • Operation: operation

OnBeforeDeleteSession    (declared in TROCustomSessionManager)

Fires before deleting session.

property OnBeforeDeleteSession: TDeleteSessionEvent read write
delegate:  procedure OnBeforeDeleteSession(const aSessionID: TGUID; IsExpired: Boolean)

OnCommitTransaction

Fires when a transaction should be committed. You can handle this event to determine if the transaction should be committed (default) or not.

property OnCommitTransaction: TRODBSessionManagerTransactionEvent read write
delegate:  procedure OnCommitTransaction(Sender: TROCustomSessionManager)

OnConvertGUID

Fires whenever a Session ID is used to access the database, allowing to convert the actual GUIDs used by the session management to a different format for storage in a database.

property OnConvertGUID: TConvertGUIDEvent read write
delegate:  function OnConvertGUID(Sender: TROCustomSessionManager; const aGUID: TGUID): string

OnCustomCreateSession    (declared in TROCustomSessionManager)

Fires before the session is created. It allows to return existing session for given session ID

property OnCustomCreateSession: TROCustomSessionCreationEvent read write
delegate:  procedure OnCustomCreateSession(const aSessionID: TGUID; var Session: TROSession)

OnDatasetExecute

Fired when aDataset should be executed. if event isn't assigned, aDataset.PSExecute is called

property OnDatasetExecute: TRODBSessionManagerDatasetExecute read write
delegate:  procedure OnDatasetExecute(Sender: TROCustomSessionManager; aDataset: TDataset)

OnDatasetGetParams

Fired when parameters should be retrieved. if event isn't assigned, aDataset.PSGetParam is called

property OnDatasetGetParams: TRODBSessionManagerDatasetGetParams read write
delegate:  function OnDatasetGetParams(Sender: TROCustomSessionManager; aDataset: TDataset): TParams

OnDatasetSetParams

Fired when parameters should be set. if event isn't assigned, aDataset.PSSetParam is called

property OnDatasetSetParams: TRODBSessionManagerDatasetSetParams read write
delegate:  procedure OnDatasetSetParams(Sender: TROCustomSessionManager; aDataset: TDataset; aParams: TParams)

OnException    (declared in TROCustomSessionManager)

Fires when an exception is occuring

property OnException: TROSessionExceptionEvent read write
delegate:  procedure OnException(aSessionID: TGUID; anException: Exception; var aRetry: Boolean)

OnInTransaction

Fires when a currect state of transaction is requested

property OnInTransaction: TRODBSessionManagerInTransactionEvent read write
delegate:  function OnInTransaction(Sender: TROCustomSessionManager): Boolean

OnMaxSessionsReached    (declared in TROCustomSessionManager)

Fires when maximum count of allowed sessions is reached

property OnMaxSessionsReached: TROMaxSessionsReachedEvent read write
delegate:  procedure OnMaxSessionsReached(var aFail: Boolean)

OnRollbackTransaction

Fires when a transaction should be rolling back. You can handle this event to determine if the transaction should be rolling back (default) or not.

property OnRollbackTransaction: TRODBSessionManagerTransactionEvent read write
delegate:  procedure OnRollbackTransaction(Sender: TROCustomSessionManager)

OnSessionCreated    (declared in TROCustomSessionManager)

Gets triggered after a new Session has been created. You can use it to perform initialization functions or fill the session with default values.

property OnSessionCreated: TSessionEvent read write
delegate:  procedure OnSessionCreated(const aSession: TROSession)

OnSessionDeleted    (declared in TROCustomSessionManager)

Gets triggered after the Session has been deleted. You can use it to perform some finalization functions.

property OnSessionDeleted: TDeleteSessionEvent read write
delegate:  procedure OnSessionDeleted(const aSessionID: TGUID; IsExpired: Boolean)

OnStartTransaction

Fires when a transaction should be started. You can handle this event to determine if the transaction should be started (default) or not.

property OnStartTransaction: TRODBSessionManagerTransactionEvent read write
delegate:  procedure OnStartTransaction(Sender: TROCustomSessionManager)

RegisterSessionsChangesListener  protected virtual    (declared in TROCustomSessionManager)

Attaches a new IROSessionsChangesListener listener.

procedure RegisterSessionsChangesListener(aListener: IROSessionsChangesListener)

Parameters:

  • aListener: New listener

ReleaseSession    (declared in TROCustomSessionManager)

Releases the previously acquired session.

procedure ReleaseSession(var aSession: TROSession; NewSession: Boolean)

Parameters:

  • aSession: given session
  • NewSession: newly created session or not

ROFreeNotification    (declared in TROComponent)

Forwards notification messages to all owned components.

procedure ROFreeNotification(aComponent: TComponent)

Parameters:

  • aComponent: component

RORemoveFreeNotification    (declared in TROComponent)

Forwards notification messages to all owned components.

procedure RORemoveFreeNotification(aComponent: TComponent)

Parameters:

  • aComponent: component

SelectAllDataset

Sets the TDataset component that will be used to get the complete list of session IDs from the database.

property SelectAllDataset: TDataSet read write

SelectDataset

Determines the TDataset component that will be used to SELECT (i.e. retrieve) sessions from the database, when needed.

property SelectDataset: TDataset read write

SendRemoveNotification  protected    (declared in TROComponent)

Forwards notification messages to all owned components.

procedure SendRemoveNotification(aComponent: TComponent)

Parameters:

  • aComponent: component

SessionCheckInterval

Internal for checking session in minutes. default value is 15 minutes.

property SessionCheckInterval: Integer read write

SessionDuration

The time, in minutes, that sessions will persist before timing out (default is 15 minutes).The timeout for each individual session will be reset every time the session is accessed; after SessionDuration minutes have passed without access to the session, it will be discarded. The exact handling of the timeout processing depends on the implementation of the specific session manager, which might check session timeouts at intervals. Therefore, sessions might live slightly longer then the specified timeout.

property SessionDuration: Integer read write

ShouldNotifySessionsChanges  protected    (declared in TROCustomSessionManager)

function ShouldNotifySessionsChanges: Boolean

StoreAsUTCTimeStamp

Store timestamp as UTC in DB

property StoreAsUTCTimeStamp: Boolean read write

TestLastAccess  protected    (declared in TROCustomSessionManager)

function TestLastAccess(const aLastAccess: TDateTime): Boolean

Parameters:

  • aLastAccess:

UnlockForReading  protected    (declared in TROCustomSessionManager)

procedure UnlockForReading

UnlockForWriting  protected    (declared in TROCustomSessionManager)

procedure UnlockForWriting

UnRegisterSessionsChangesListener  protected virtual    (declared in TROCustomSessionManager)

Detaches a previously attached aListener.

procedure UnRegisterSessionsChangesListener(aListener: IROSessionsChangesListener)

Parameters:

  • aListener: Known listener

UpdateDataset

This TDataset component will be used to UPDATE sessions in the database, when they have been touched by the user.

property UpdateDataset: TDataset read write

 

AutoTransaction

Controls of using implicit (True) or explicit (False) database transactions.

property AutoTransaction: Boolean read write

Clearing  protected    (declared in TROCustomSessionManager)

internal flag that is set when session are clearing

property Clearing: Boolean read

ClearSessionsDataset

This TDataset component will be used to DELETE all sessions from the database, when ClearSessions is called or if the ClearSessionsOnCreate or ClearSessionsOnDestroy properties are set to true.

property ClearSessionsDataset: TDataset read write

ClearSessionsOnCreate

Forces the session manager to clear the database of old sessions when the component is created (i.e. usually at application startup).

property ClearSessionsOnCreate: Boolean read write

ClearSessionsOnDestroy

Determines whether the session manager should clear the database of old sessions when the component is destroyed (i.e. usually at application shutdown).

property ClearSessionsOnDestroy: Boolean read write

DeleteDataset

This TDataset component will be used to DELETE sessions from the database, when they expire or are explicitly deleted.

property DeleteDataset: TDataset read write

FieldNameCreated

Sets the database field used to store the time and date the session was originally created.

property FieldNameCreated: string read write

FieldNameData

Defines the database field used to store the session data. This must be a BLOB field.

property FieldNameData: string read write

FieldNameLastAccessed

Sets the database field used to store the time and date the session was last accessed.

property FieldNameLastAccessed: string read write

FieldNameSessionID

Determines the database field used to store the session ID. This must be a GUID field, or a string field of 38 characters.

property FieldNameSessionID: string read write

GetCountDataset

This TDataset component will be used to get the number of sessions contained in the database.

property GetCountDataset: TDataset read write

InsertDataset

Defines the TDataset component that will be used to INSERT new sessions into the database, when they are first created.

property InsertDataset: TDataset read write

MaxSessions    (declared in TROCustomSessionManager)

Specifies the maximum number of sessions that will be allowed. -1 (the default) indicates that no limit on number of sessions will be enforced. Allowing a server to run without enforcing any limit on the number of sessions might pose a security risk, as malicious clients could theoretically start an infinite number of sessions by performing repeated requests with changing Client IDs, until server memory is depleted. You should make sure to either set a limit, or tie session creation to user authentication, so that only valid client users can obtain a session(and possibly only one session per login).

property MaxSessions: Integer read write

SelectAllDataset

Sets the TDataset component that will be used to get the complete list of session IDs from the database.

property SelectAllDataset: TDataSet read write

SelectDataset

Determines the TDataset component that will be used to SELECT (i.e. retrieve) sessions from the database, when needed.

property SelectDataset: TDataset read write

SessionCheckInterval

Internal for checking session in minutes. default value is 15 minutes.

property SessionCheckInterval: Integer read write

SessionDuration

The time, in minutes, that sessions will persist before timing out (default is 15 minutes).The timeout for each individual session will be reset every time the session is accessed; after SessionDuration minutes have passed without access to the session, it will be discarded. The exact handling of the timeout processing depends on the implementation of the specific session manager, which might check session timeouts at intervals. Therefore, sessions might live slightly longer then the specified timeout.

property SessionDuration: Integer read write

StoreAsUTCTimeStamp

Store timestamp as UTC in DB

property StoreAsUTCTimeStamp: Boolean read write

UpdateDataset

This TDataset component will be used to UPDATE sessions in the database, when they have been touched by the user.

property UpdateDataset: TDataset read write

 

constructor Create  override

Standard component constructor

constructor Create(aOwner: TComponent)

Parameters:

  • aOwner: Owner

Assign  override

Copies the contents of another, similar object.

procedure Assign(Source: TPersistent)

Parameters:

  • Source: Instance whose properties will be copied

CheckProperties  override

Validates the session manager properties.

procedure CheckProperties

CheckSessionIsExpired (TROSession): Boolean  overload    (declared in TROCustomSessionManager)

Checks state of given session.

function CheckSessionIsExpired(aSession: TROSession): Boolean

Parameters:

  • aSession: Given session.

CheckSessionIsExpired (TGUID): Boolean  overload    (declared in TROCustomSessionManager)

Checks state of given session or not.

function CheckSessionIsExpired(const aSessionID: TGUID): Boolean

Parameters:

  • aSessionID: Session ID

ClearSessions    (declared in TROCustomSessionManager)

Discards all sessions within the session manager, so that any new call from a client will start with a fresh session.

procedure ClearSessions(OnlyExpired: Boolean)

Parameters:

  • OnlyExpired: process only expired sessions or not.

CreateSession    (declared in TROCustomSessionManager)

Creates a new session with provided ID.

function CreateSession(const aSessionID: TGUID): TROSession

Parameters:

  • aSessionID: Session ID

CreateTimerByRequest  protected    (declared in TROCustomSessionManager)

Creates internal timer.

procedure CreateTimerByRequest

DeleteSession    (declared in TROCustomSessionManager)

Deletes the session with specified ID.

procedure DeleteSession(const aSessionID: TGUID; IsExpired: Boolean)

Parameters:

  • aSessionID: Session ID
  • IsExpired: current state of session

DeleteTemporarySession    (declared in TROCustomSessionManager)

Deletes the temporary session.

procedure DeleteTemporarySession(var Session: TROSession)

Parameters:

  • Session: given session.

DoClearSessions  protected override

Discards all sessions within the session manager, so that any new call from a client will start with a fresh session.

procedure DoClearSessions(OnlyExpired: Boolean)

Parameters:

  • OnlyExpired: process only expired sessions or not.

DoConvertGUID  protected virtual

Calls to OnConvertGUID (if set) or uses GUIDToString for getting a text representation of given aGUID.

function DoConvertGUID(const aGUID: TGUID): string

Parameters:

  • aGUID: guid

DoCreateSession  protected virtual    (declared in TROCustomSessionManager)

Creates a new session with provided ID.

function DoCreateSession(const aSessionID: TGUID): TROSession

Parameters:

  • aSessionID: Session ID

DoDeleteSession  protected override

Deletes the session with specified ID.

procedure DoDeleteSession(const aSessionID: TGUID; IsExpired: Boolean)

Parameters:

  • aSessionID: Session ID
  • IsExpired: current state of session

DoFindSession  protected override

Finds session with the specified GUID

function DoFindSession(const aSessionID: TGUID; aUpdateTime: Boolean): TROSession

Parameters:

  • aSessionID: Session ID.
  • aUpdateTime: Update LastAccess of found session or not

DoGetAllSessions  protected override

Returns a string list containing the IDs of all currently active sessions.

procedure DoGetAllSessions(Dest: TStringList)

Parameters:

  • Dest: destination

DoGetSessionCount  protected override

Returns the session count.

function DoGetSessionCount: Integer

DoNotifySessionsChangesListener  protected virtual    (declared in TROCustomSessionManager)

Notifies attached listeners about changes

procedure DoNotifySessionsChangesListener(const aSessionID: TGUID; aSessionAction: TROSessionsActions; Sender: TObject)

Parameters:

  • aSessionID: Session ID
  • aSessionAction: action
  • Sender: sender

DoReleaseSession  protected override

Releases the previously acquired session.

procedure DoReleaseSession(aSession: TROSession; NewSession: Boolean)

Parameters:

  • aSession: given session
  • NewSession: newly created session or not

DoTimerTick  protected virtual    (declared in TROCustomSessionManager)

Clears expired sessions.

procedure DoTimerTick(CurrentTickCount: Cardinal)

Parameters:

  • CurrentTickCount: ignored

FindSession    (declared in TROCustomSessionManager)

Finds session with the specified GUID

function FindSession(const aSessionID: TGUID; aUpdateTime: Boolean): TROSession

Parameters:

  • aSessionID: Session ID.
  • aUpdateTime: Update LastAccess of found session or not

GetAllSessions  overload    (declared in TROCustomSessionManager)

function GetAllSessions: TROSessionIDs

GetAllSessions (TStringList)  overload    (declared in TROCustomSessionManager)

Returns a string list containing the IDs of all currently active sessions. Depending on the session manager and on your application architecture, this list can be huge, especially when using a database based session list that is shared by a large server farm. Obtaining the full list of sessions can be a costly process.

procedure GetAllSessions(Dest: TStringList)

Parameters:

  • Dest: destination

GetSessionCount    (declared in TROCustomSessionManager)

Returns the session count.

function GetSessionCount: Integer

IsSessionPresent    (declared in TROCustomSessionManager)

function IsSessionPresent(const aSessionID: TGUID): Boolean

Parameters:

  • aSessionID:

KillTimer  protected    (declared in TROCustomSessionManager)

Kills internal timer

procedure KillTimer

LockForReading  protected    (declared in TROCustomSessionManager)

procedure LockForReading

LockForWriting  protected    (declared in TROCustomSessionManager)

procedure LockForWriting

Notification  protected override

Forwards notification messages to all owned components.

procedure Notification(AComponent: TComponent; Operation: TOperation)

Parameters:

  • AComponent: component
  • Operation: operation

RegisterSessionsChangesListener  protected virtual    (declared in TROCustomSessionManager)

Attaches a new IROSessionsChangesListener listener.

procedure RegisterSessionsChangesListener(aListener: IROSessionsChangesListener)

Parameters:

  • aListener: New listener

ReleaseSession    (declared in TROCustomSessionManager)

Releases the previously acquired session.

procedure ReleaseSession(var aSession: TROSession; NewSession: Boolean)

Parameters:

  • aSession: given session
  • NewSession: newly created session or not

ROFreeNotification    (declared in TROComponent)

Forwards notification messages to all owned components.

procedure ROFreeNotification(aComponent: TComponent)

Parameters:

  • aComponent: component

RORemoveFreeNotification    (declared in TROComponent)

Forwards notification messages to all owned components.

procedure RORemoveFreeNotification(aComponent: TComponent)

Parameters:

  • aComponent: component

SendRemoveNotification  protected    (declared in TROComponent)

Forwards notification messages to all owned components.

procedure SendRemoveNotification(aComponent: TComponent)

Parameters:

  • aComponent: component

ShouldNotifySessionsChanges  protected    (declared in TROCustomSessionManager)

function ShouldNotifySessionsChanges: Boolean

TestLastAccess  protected    (declared in TROCustomSessionManager)

function TestLastAccess(const aLastAccess: TDateTime): Boolean

Parameters:

  • aLastAccess:

UnlockForReading  protected    (declared in TROCustomSessionManager)

procedure UnlockForReading

UnlockForWriting  protected    (declared in TROCustomSessionManager)

procedure UnlockForWriting

UnRegisterSessionsChangesListener  protected virtual    (declared in TROCustomSessionManager)

Detaches a previously attached aListener.

procedure UnRegisterSessionsChangesListener(aListener: IROSessionsChangesListener)

Parameters:

  • aListener: Known listener

 

OnBeforeDeleteSession    (declared in TROCustomSessionManager)

Fires before deleting session.

property OnBeforeDeleteSession: TDeleteSessionEvent read write
delegate:  procedure OnBeforeDeleteSession(const aSessionID: TGUID; IsExpired: Boolean)

OnCommitTransaction

Fires when a transaction should be committed. You can handle this event to determine if the transaction should be committed (default) or not.

property OnCommitTransaction: TRODBSessionManagerTransactionEvent read write
delegate:  procedure OnCommitTransaction(Sender: TROCustomSessionManager)

OnConvertGUID

Fires whenever a Session ID is used to access the database, allowing to convert the actual GUIDs used by the session management to a different format for storage in a database.

property OnConvertGUID: TConvertGUIDEvent read write
delegate:  function OnConvertGUID(Sender: TROCustomSessionManager; const aGUID: TGUID): string

OnCustomCreateSession    (declared in TROCustomSessionManager)

Fires before the session is created. It allows to return existing session for given session ID

property OnCustomCreateSession: TROCustomSessionCreationEvent read write
delegate:  procedure OnCustomCreateSession(const aSessionID: TGUID; var Session: TROSession)

OnDatasetExecute

Fired when aDataset should be executed. if event isn't assigned, aDataset.PSExecute is called

property OnDatasetExecute: TRODBSessionManagerDatasetExecute read write
delegate:  procedure OnDatasetExecute(Sender: TROCustomSessionManager; aDataset: TDataset)

OnDatasetGetParams

Fired when parameters should be retrieved. if event isn't assigned, aDataset.PSGetParam is called

property OnDatasetGetParams: TRODBSessionManagerDatasetGetParams read write
delegate:  function OnDatasetGetParams(Sender: TROCustomSessionManager; aDataset: TDataset): TParams

OnDatasetSetParams

Fired when parameters should be set. if event isn't assigned, aDataset.PSSetParam is called

property OnDatasetSetParams: TRODBSessionManagerDatasetSetParams read write
delegate:  procedure OnDatasetSetParams(Sender: TROCustomSessionManager; aDataset: TDataset; aParams: TParams)

OnException    (declared in TROCustomSessionManager)

Fires when an exception is occuring

property OnException: TROSessionExceptionEvent read write
delegate:  procedure OnException(aSessionID: TGUID; anException: Exception; var aRetry: Boolean)

OnInTransaction

Fires when a currect state of transaction is requested

property OnInTransaction: TRODBSessionManagerInTransactionEvent read write
delegate:  function OnInTransaction(Sender: TROCustomSessionManager): Boolean

OnMaxSessionsReached    (declared in TROCustomSessionManager)

Fires when maximum count of allowed sessions is reached

property OnMaxSessionsReached: TROMaxSessionsReachedEvent read write
delegate:  procedure OnMaxSessionsReached(var aFail: Boolean)

OnRollbackTransaction

Fires when a transaction should be rolling back. You can handle this event to determine if the transaction should be rolling back (default) or not.

property OnRollbackTransaction: TRODBSessionManagerTransactionEvent read write
delegate:  procedure OnRollbackTransaction(Sender: TROCustomSessionManager)

OnSessionCreated    (declared in TROCustomSessionManager)

Gets triggered after a new Session has been created. You can use it to perform initialization functions or fill the session with default values.

property OnSessionCreated: TSessionEvent read write
delegate:  procedure OnSessionCreated(const aSession: TROSession)

OnSessionDeleted    (declared in TROCustomSessionManager)

Gets triggered after the Session has been deleted. You can use it to perform some finalization functions.

property OnSessionDeleted: TDeleteSessionEvent read write
delegate:  procedure OnSessionDeleted(const aSessionID: TGUID; IsExpired: Boolean)

OnStartTransaction

Fires when a transaction should be started. You can handle this event to determine if the transaction should be started (default) or not.

property OnStartTransaction: TRODBSessionManagerTransactionEvent read write
delegate:  procedure OnStartTransaction(Sender: TROCustomSessionManager)