Easy class for registering a callback function that receives messages on an MQTT topic and handles them appropriately. Behaves similarly to HttpResponseHandler. More...

#include <mqtt.h>

Inherits MQTT::mqtt_leaf.

Public Member Functions
	SubHandler (SubHandlerCb handler, const char topicFilter, Client mClient=NULL, uint16_t flags=0)
	SubHandler Constructor for a standalone SubHandler object.

virtual ValueTestResult	TestOrSetValue (ParsedJsonDataSet &pjs, bool setVal) override
	SubHandler::TestOrSetValue Test whether the current index of a JSON dataset is valid for this object, or assign the value at the current index of the dataset to this object.

virtual int	SubscribeEvent (int mqttFd, PacketInfo::Msg *msg) override
	SubHandler::SubscribeEvent Handle a message sent by the Broker triggered by this object's Subscription.

Public Member Functions inherited from MQTT::mqtt_leaf
	~mqtt_leaf ()
	~mqtt_leaf Destructor for base mqtt_leaf

void	RemoveFromTree ()
	Remove this object from it's parent tree.

bool	NameMatch (const char *cp)
	Determine whether a given name matches this object.

virtual int	GetPubTopicName (NBString &s)
	Get the Topic Name this object Publishes to.

virtual int	GetSubTopicFilter (NBString &s)
	Get the Subscription Topic Filter this object Subscribes to.

virtual int	GetRenderLength (eObj_Serialize_t form=eObj_Serialize_CURRENT_FORM)
	Get the number of bytes used to serialize this object in a particular format.

int	Publish (int waitForCompletion=-1)
	Publishes the current MQTT object, optionally waiting for completion.

void	SetPublishInterval (uint32_t intervalPeriodTicks)
	Sets or clears an automatic publishing interval for this MQTT object.

virtual void	SetSerializationForm (eObj_Serialize_t form)
	Set the default serialization format for this object.

eObj_Serialize_t	GetSerializationForm ()
	Get the default serialization format for this object.

virtual void	SetFlags (uint16_t newFlags)
	Set additional behavioral flags for this object.

virtual void	ClearFlags (uint16_t delFlags)
	Clear behavioral flags from this object.

uint16_t	GetFlags ()
	Get the behavioral flags set for this object.

int	getPriority ()
	Get the message priority for this object.

Protected Member Functions
virtual int	ParseFd (int mqttFd) override
	SubHandler::ParseFd Parse the data from a file descriptor according to this object's current default serialization method and assign the value.

virtual int	RenderToBuffer (eObj_Serialize_t form, uint8_t *buf, int buflen) override
	SubHandler::RenderToBuffer Render this object to an output buffer.

virtual int	RenderToFd (eObj_Serialize_t form, int fd) override
	SubHandler::RenderToFd Render this object to an output socket.

Protected Member Functions inherited from MQTT::mqtt_leaf
	mqtt_leaf (const char topic, Client mClient, uint16_t flags=(eObj_Flag_PubOnWrite\|eObj_Flag_Subscribe\|eObj_Flag_Sub_NoLocal))
	Constructor for mqtt_leaf objects.

	mqtt_leaf (mqtt_leaf &parent, const char topic, Client mClient, uint16_t flags=(eObj_Flag_PubOnWrite\|eObj_Flag_Subscribe\|eObj_Flag_Sub_NoLocal))
	Constructor for mqtt_leaf objects.

virtual mqtt_leaf *	GetChildren ()
	Get the first child of this object.

virtual mqtt_leaf *	AddChild (mqtt_leaf *child)
	Add an MqttObj as a child to this object.

virtual mqtt_leaf *	RemoveFirstChild ()
	Remove the first child from this object.

void	ForEachLeaf (LeafCallBack p, void pd)
	Call a function on each element of the MqttObj tree with this object as the root.

void	RootParse (ParsedJsonDataSet &pjs)
	Assign to this object tree from a JSON dataset.

bool	MatchId (ParsedJsonDataSet &pjs)
	Determine whether the JSON dataset's current index matches this object's name.

int	QueuePublish ()
	Queue this object to be Published via the registered Client.

int	QueueSubscribe ()
	Queue this object to be Subscribed via the registered Client.

int	QueueUnsubscribe ()
	Queue this object to be Unsubscribed via the registered Client.

int	Assign ()
	Perform post assignemnt operations.

uint8_t	PubState ()
	Get the Publish state.

uint8_t	SubState ()
	Get the Subscribe state of this object.

virtual void	SetPubState (uint8_t newState)
	Set the Publish state.

virtual void	SetSubState (uint8_t newState)
	Set the Subscribe state.

int	HandleSubAck (int mqttFd, PacketInfo::Msg *msg)
	Handle a Subscribe Acknowledge message from the broker for our Subscribe request.

int	HandleUnsubAck (int mqttFd, PacketInfo::Msg *msg)
	Handle an Unsubscribe Acknowledge message from the broker for our Unsubscribe request.

int	HandlePubAck (int mqttFd, PacketInfo::Msg *msg)
	Handle an Publish Acknowledge message from the broker for our Publish request.

Additional Inherited Members
Public Types inherited from MQTT::mqtt_leaf
enum	eObj_State_t
	Mqtt Object Publication/Subscription States.

Static Public Member Functions inherited from MQTT::mqtt_leaf
static int	MqttRxPublish (Client mClient, int mqttFd, PacketInfo::Msg msg, void *ctx)
	Static message handler for Publish messages received by the registered Client.

Protected Attributes inherited from MQTT::mqtt_leaf
NBInterpolatedString	topicName
	Topic name or additional branch.

eObj_Serialize_t	publishForm
	Default serialization form.

uint16_t	mFlags
	Behavioral flags.

Detailed Description

Easy class for registering a callback function that receives messages on an MQTT topic and handles them appropriately. Behaves similarly to HttpResponseHandler.

Constructor & Destructor Documentation

◆ SubHandler()

MQTT::SubHandler::SubHandler	(	SubHandlerCb	handler,
		const char *	topicFilter,
		Client *	mClient = NULL,
		uint16_t	flags = 0 )

SubHandler Constructor for a standalone SubHandler object.

Parameters

handler	Function that should be called when a message is received
*topicFilter	Mqtt Topic Filter to Subcribe to
*mClient	Pointer to Client to register with. If NULL, it will be registered with the first created Client.
flags	Behavioral flags to set on the created object

Member Function Documentation

◆ ParseFd()

virtual int MQTT::SubHandler::ParseFd ( int mqttFd )

overrideprotectedvirtual

SubHandler::ParseFd Parse the data from a file descriptor according to this object's current default serialization method and assign the value.

Parameters

mqttFd File descriptor to read from.

Returns: eResult_t return code

Implements MQTT::mqtt_leaf.

◆ RenderToBuffer()

virtual int MQTT::SubHandler::RenderToBuffer	(	eObj_Serialize_t	form,
		uint8_t *	buf,
		int	buflen )

overrideprotectedvirtual

SubHandler::RenderToBuffer Render this object to an output buffer.

Parameters

form	Serialization format to render as
*buf	Pointer to output buffer
buflen	Size of the output buffer

Returns: Length of the rendered data

Implements MQTT::mqtt_leaf.

◆ RenderToFd()

virtual int MQTT::SubHandler::RenderToFd	(	eObj_Serialize_t	form,
		int	fd )

overrideprotectedvirtual

SubHandler::RenderToFd Render this object to an output socket.

Parameters

form	Serialization format to render as
fd	File descriptor to render to

Returns: Length of the rendered data

Implements MQTT::mqtt_leaf.

◆ SubscribeEvent()

virtual int MQTT::SubHandler::SubscribeEvent	(	int	mqttFd,
		PacketInfo::Msg *	msg )

overridevirtual

SubHandler::SubscribeEvent Handle a message sent by the Broker triggered by this object's Subscription.

Parameters

mqttFd	File Descriptor to read any additional message data from
*msg	Pointer to message received from the Broker

Returns: eResult_t return code

Reimplemented from MQTT::mqtt_leaf.

◆ TestOrSetValue()

virtual ValueTestResult MQTT::SubHandler::TestOrSetValue	(	ParsedJsonDataSet &	pjs,
		bool	setVal )

overridevirtual

SubHandler::TestOrSetValue Test whether the current index of a JSON dataset is valid for this object, or assign the value at the current index of the dataset to this object.

Parameters

&pjs	The JSON dataset to use
setVal	true: Assign from the value at the current index, false: test if current index is valid for this object

Returns: ValueTestResult indicating the validity of the current index

Implements MQTT::mqtt_leaf.

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

mqtt.h

Public Member Functions

Protected Member Functions

Additional Inherited Members

Detailed Description

Constructor & Destructor Documentation

◆ SubHandler()

Member Function Documentation

◆ ParseFd()

◆ RenderToBuffer()

◆ RenderToFd()

◆ SubscribeEvent()

◆ TestOrSetValue()