Wombat::MamaSubscription

Subscription class, derives from a basic subscription.

Inherits from Wombat.MamaBasicSubscription, Wombat.MamaWrapper, IDisposable

Public Functions

	Name
	MamaSubscription() Allocate memory for a new subscription. The subscription is not actually created until a call to one of the create() functions is made. Memory must be freed using the deallocate()
void	activate() Activate a subscription that has been set up by calling the setup function. Subscription creation actually occurs on the throttle queue. An individual subscription cannot be assumed to be fully created until its onCreate callback has been successfully invoked. The subscription rate can be governed via the MamaTransport.setOutboundThrottle function. Any subscription properties should be set prior to calling this function.
void	create(MamaQueue queue, MamaSubscriptionCallback callback, MamaSource source, string symbol) Set up and activate a subscriber using the throttle queue. This method is equivalent to calling setup() followed by activate().
void	create(MamaQueue queue, MamaSubscriptionCallback callback, MamaSource source, string symbol, object closure) Set up and activate a subscriber using the throttle queue. This method is equivalent to calling setup() followed by activate().
void	createBasic(MamaTransport transport, MamaQueue queue, MamaSubscriptionCallback callback, string symbol) This function will create the basic subscription without marketdata semantics. To pass a closure use the overload. This overload provides access to the basic subscription with the MamaSubscriptionCallback rather than the MamaBasicSubscriptionCallback interface. Instantiating the base class directly will provide better performance.
void	createBasic(MamaTransport transport, MamaQueue queue, MamaSubscriptionCallback callback, string symbol, object closure) This function will create the basic subscription without marketdata semantics. This overload provides access to the basic subscription with the MamaSubscriptionCallback rather than the MamaBasicSubscriptionCallback interface. Instantiating the base class directly will provide better performance.
void	deactivate() Deactivate an active subscription. The onDestroy callback will be invoked whenever the subscription has been fully deactivated.
int	getPreInitialCacheSize() Return the initial value cache size.
bool	getReceivedInitial() Whether an Initial has been received for the specified subscription. Returns true if initial has been received.
void	setPreInitialCacheSize(int cacheSize) Set the number of messages to cache for each symbol before the initial value arrives. This allows the subscription to recover when the initial value arrives late (after a subsequent trade or quote already arrived). For group subscription, a separate cache is used for each group member. The default is 10.
void	setRecoverGaps(bool recover) If this flag is set then the subscription will attempt to recover from a sequence number gap.
void	setRequiresInitial(bool requiresInitial) Whether an initial value is required for the specified subscription. This only applies to market data subscriptions and not to basic subscriptions. Default value of true indicating that initial values are required.
void	setRetries(int retries) Set the number of retries when requesting recaps.
void	setServiceLevel(mamaServiceLevel svcLevel) Set the service level without any other options. This method must be invoked before create().
void	setServiceLevel(mamaServiceLevel svcLevel, int serviceLevelOpt) Set the service level and an passes an optional service level parameter. This method must be invoked before create().
void	setSubscriptionType(mamaSubscriptionType type) Set the subscription type for the subscription being created. If not called the subscription type defaults to MAMA_SUBSC_TYPE_NORMAL. See mamaSubscriptionType enum for valid values.
void	setTimeout(double timeout) Set the timeout for this subscription. The timeout is used for requesting recaps.
void	setup(MamaQueue queue, MamaTransport transport, MamaSubscriptionCallback callback, string sourceName, string symbol, object closure) Set the parameters for a subscription that may be actually activated later. Activate the subscription using MamaSubscription.activate().
void	setup(MamaQueue queue, MamaSubscriptionCallback callback, MamaSource source, string symbol, object closure) Set the parameters for a subscription that may be actually activated later. Activate the subscription using MamaSubscription.activate().
void	setup(MamaQueue queue, MamaSubscriptionCallback callback, MamaSource source, string symbol) Set the parameters for a subscription that may be actually activated later. Activate the subscription using MamaSubscription.activate(). This overload passes a null value for the closure.

Public Properties

	Name
string	subscSource Read only property returns the subscription source.

Additional inherited members

Protected Classes inherited from Wombat.MamaBasicSubscription

	Name
class	MamaBasicSubscriptionImpl This impl will perform the work of invoking user supplied callbacks, it is held to ensure that the user can destroy and recreate the parent subscription during the callbacks.
struct	NativeMethods

Public Functions inherited from Wombat.MamaBasicSubscription

	Name
delegate void	OnSubscriptionCreateDelegate(IntPtr nativeHandle, IntPtr closure) This delegate describes that native callback function that is invoked whenever the subscription has been created.
delegate void	OnSubscriptionDestroyDelegate(IntPtr nativeHandle, IntPtr closure) This delegate describes the native function invoked whenever the subscription has been either destroyed or deactivated.
delegate void	OnSubscriptionErrorDelegate(IntPtr nativeHandle, int status, IntPtr platformError, string subject, IntPtr closure) This delegate describes the native function invoked if an error occurs during prior to subscription creation or if the subscription receives a message for an un-entitled subject. If the status is MAMA_MSG_STATUS_NOT_ENTITTLED the subject parameter is the specific unentitled subject. If the subscription subject contains wildcards, the subscription may still receive messages for other entitled subjects. Note wildcard subscriptions are not supported on all platforms.
delegate void	OnSubscriptionGapDelegate(IntPtr nativeHandle, IntPtr closure) This delegate describes the native function invoked when a sequence number gap is detected. At this point the topic is considered stale and the subscription will not receive further messages until the feed handler satisfies a recap request.
delegate void	OnSubscriptionMessageDelegate(IntPtr nativeHandle, IntPtr msg, IntPtr closure, IntPtr itemClosure) This delegate describes the native function that is invoked whenever a message arrives.
delegate void	OnSubscriptionQualityDelegate(IntPtr nativeHandle, int quality, string symbol, short cause, string platforminfo, IntPtr closure) This delegate describes the native function invoked to indicate a data quality event.
delegate void	OnSubscriptionRecapRequestDelegate(IntPtr nativeHandle, IntPtr closure) This delegate describes the native function invoked when a recap is requested upon detecting a sequence number gap.
	MamaBasicSubscription() Constructor constructs a new basic subscription including creating the underlying native subscription.
void	deallocate() Free the memory for a mamaSubscription which was allocated via a call to constructor. This function will call destroy() if the subscription has not already been destroyed. Calling this function will reduce time during finalization.
void	destroy() This function will destroy the subscription, it must be called from the same thread that is processing the queue for the subscription. Use destroyEx to destroy the subscription from any thread. Note that the subscription will not be fully destroyed until the onDestroy callback is received.
void	destroyEx() Destroy the subscription. This function is another option to destroy the resources associated with the subscription It will schedule the destroy() of the subscription on the queue on which it dispatches. This function does not free the memory associated with the subscription. create() can be called again after this function has been called. After the Subscription is effectively destroyed, the OnDestroy callback will be triggered for it.

Protected Functions inherited from Wombat.MamaBasicSubscription

	Name
virtual override MamaStatus.mamaStatus	DestroyNativePeer() This will be called by the base class to de-allocate the native subscription. MamaWrapper.DestroyNativePeer

Public Properties inherited from Wombat.MamaBasicSubscription

	Name
mamaSubscriptionState	State This read only property returns the current state of the subscription, this function should be used in preference to the mamaSubscription_isActive or mamaSubscription_isValid functions. function is thread-safe. The state will be one of the mamaSubscriptionState enumeration values.
object	subscClosure Read only property returns the closure passed to the create function.
MamaQueue	subscQueue Read only property returns the queue.
string	subscSymbol Read only property returns the symbol for this subscription.

Protected Attributes inherited from Wombat.MamaBasicSubscription

	Name
object	mClosure The closure passed to the create function. This member is declared as protected as there is a public read only property to access it.
MamaQueue	mQueue The queue passed to the create function. This member is declared as protected as there is a public read only property to access it.
MamaTransport	mTransport The transport passed to the create function. This member is declared as protected as there is a public read only property to access it.
NativeMethods.SubscriptionCallbacks	mCallbackDelegates This structure holds all of the callback delegates, it is initialised in the static constructor.

Public Functions inherited from Wombat.MamaWrapper

	Name
void	Dispose() Destroys the underlying peer object and unbinds the wrapper from it.
void	setNativeHandle(IntPtr nHandle) Sets the native handle of the native peer object. Should only be used by subclasses and in the same assembly.

Protected Functions inherited from Wombat.MamaWrapper

	Name
	MamaWrapper() Constructs a new wrapper object but doesn’t create it. If the object is not explicitly disposed it will remain registered for finalization and will attempt the destroy the native peer object when finalized.
	MamaWrapper(IntPtr nativeHandle) Constructs a managed wrapper from an existing native peer. The peer object will not be automatically finalized
virtual void	Dispose(bool disposing, bool destroyNativeHandle =true) The actual implementation of Dispose - called by both the Dispose method and the finalizer.
virtual abstract MamaStatus.mamaStatus	DestroyNativePeer() =0 Subclasses must do whatever is necessary with the native handle in the overridden method in order to destroy the native peer object. If the destruction went successfully, the overridden method must return MamaStatus.mamaStatus.MAMA_STATUS_OK, or a suitable error code otherwise
virtual void	OnDispose()

Protected Attributes inherited from Wombat.MamaWrapper

	Name
IntPtr	nativeHandle the handle to the native peer object

Public Functions Documentation

function MamaSubscription

MamaSubscription()

Allocate memory for a new subscription. The subscription is not actually created until a call to one of the create() functions is made. Memory must be freed using the deallocate()

function activate

void activate()

Activate a subscription that has been set up by calling the setup function. Subscription creation actually occurs on the throttle queue. An individual subscription cannot be assumed to be fully created until its onCreate callback has been successfully invoked. The subscription rate can be governed via the MamaTransport.setOutboundThrottle function. Any subscription properties should be set prior to calling this function.

function create

void create(
    MamaQueue queue,
    MamaSubscriptionCallback callback,
    MamaSource source,
    string symbol
)

Set up and activate a subscriber using the throttle queue. This method is equivalent to calling setup() followed by activate().

Parameters:

queue The mama queue.
callback The callback.
source The MamaSource identifying the publisher for this symbol.
symbol The symbol for the listener.

function create

void create(
    MamaQueue queue,
    MamaSubscriptionCallback callback,
    MamaSource source,
    string symbol,
    object closure
)

Set up and activate a subscriber using the throttle queue. This method is equivalent to calling setup() followed by activate().

Parameters:

queue The mama queue.
callback The callback.
source The MamaSource identifying the publisher for this symbol.
symbol The symbol for the listener.
closure The caller supplied closure.

function createBasic

void createBasic(
    MamaTransport transport,
    MamaQueue queue,
    MamaSubscriptionCallback callback,
    string symbol
)

This function will create the basic subscription without marketdata semantics. To pass a closure use the overload. This overload provides access to the basic subscription with the MamaSubscriptionCallback rather than the MamaBasicSubscriptionCallback interface. Instantiating the base class directly will provide better performance.

Parameters:

transport The MamaTransport.
queue The MamaQueue.
callback Provide callback function implementations to be informed of events on the subscription.
symbol The symbol to subscribe to.

function createBasic

void createBasic(
    MamaTransport transport,
    MamaQueue queue,
    MamaSubscriptionCallback callback,
    string symbol,
    object closure
)

This function will create the basic subscription without marketdata semantics. This overload provides access to the basic subscription with the MamaSubscriptionCallback rather than the MamaBasicSubscriptionCallback interface. Instantiating the base class directly will provide better performance.

Parameters:

transport The MamaTransport.
queue The MamaQueue.
callback Provide callback function implementations to be informed of events on the subscription.
symbol The symbol to subscribe to.
closure The closure that will be passed back with the callback functions.

function deactivate

void deactivate()

Deactivate an active subscription. The onDestroy callback will be invoked whenever the subscription has been fully deactivated.

function getPreInitialCacheSize

int getPreInitialCacheSize()

Return the initial value cache size.

Return: The cache size.

function getReceivedInitial

bool getReceivedInitial()

Whether an Initial has been received for the specified subscription. Returns true if initial has been received.

Return: True if an initial has been received for this subscription.

function setPreInitialCacheSize

void setPreInitialCacheSize(
    int cacheSize
)

Set the number of messages to cache for each symbol before the initial value arrives. This allows the subscription to recover when the initial value arrives late (after a subsequent trade or quote already arrived). For group subscription, a separate cache is used for each group member. The default is 10.

Parameters:

cacheSize The cache size to set.

function setRecoverGaps

void setRecoverGaps(
    bool recover
)

If this flag is set then the subscription will attempt to recover from a sequence number gap.

Parameters:

recover True to attempt recovery.

function setRequiresInitial

void setRequiresInitial(
    bool requiresInitial
)

Whether an initial value is required for the specified subscription. This only applies to market data subscriptions and not to basic subscriptions. Default value of true indicating that initial values are required.

Parameters:

requiresInitial True if the subscription requires an initial.

function setRetries

void setRetries(
    int retries
)

Set the number of retries when requesting recaps.

Parameters:

retries The number of retries.

function setServiceLevel

void setServiceLevel(
    mamaServiceLevel svcLevel
)

Set the service level without any other options. This method must be invoked before create().

Parameters:

svcLevel The service level to set.

function setServiceLevel

void setServiceLevel(
    mamaServiceLevel svcLevel,
    int serviceLevelOpt
)

Set the service level and an passes an optional service level parameter. This method must be invoked before create().

Parameters:

svcLevel The service level to set.
serviceLevelOpt The service level options.

function setSubscriptionType

void setSubscriptionType(
    mamaSubscriptionType type
)

Set the subscription type for the subscription being created. If not called the subscription type defaults to MAMA_SUBSC_TYPE_NORMAL. See mamaSubscriptionType enum for valid values.

Parameters:

type The type to set.

function setTimeout

void setTimeout(
    double timeout
)

Set the timeout for this subscription. The timeout is used for requesting recaps.

Parameters:

timeout The timeout value in seconds.

function setup

void setup(
    MamaQueue queue,
    MamaTransport transport,
    MamaSubscriptionCallback callback,
    string sourceName,
    string symbol,
    object closure
)

Set the parameters for a subscription that may be actually activated later. Activate the subscription using MamaSubscription.activate().

Parameters:

transport The MAMA transport.
queue The MAMA queue.
callback The callback interface.
sourceName The name of the source identifying the publisher for this symbol.
symbol The symbol for the listener.
closure The caller supplied closure.

function setup

void setup(
    MamaQueue queue,
    MamaSubscriptionCallback callback,
    MamaSource source,
    string symbol,
    object closure
)

Set the parameters for a subscription that may be actually activated later. Activate the subscription using MamaSubscription.activate().

Parameters:

queue The mama queue.
callback The callback.
source The MamaSource identifying the publisher for this symbol.
symbol The symbol for the listener.
closure The caller supplied closure.

function setup

void setup(
    MamaQueue queue,
    MamaSubscriptionCallback callback,
    MamaSource source,
    string symbol
)

Set the parameters for a subscription that may be actually activated later. Activate the subscription using MamaSubscription.activate(). This overload passes a null value for the closure.

Parameters:

queue The mama queue.
callback The callback.
source The MamaSource identifying the publisher for this symbol.
symbol The symbol for the listener.

Public Property Documentation

property subscSource

string subscSource;

Read only property returns the subscription source.

Updated on 2023-03-31 at 15:29:33 +0100