PubSubClient Class Reference

Main do-everything class that sketches will use. More...

#include <PubSubClient.h>

Public Types
typedef void(*	callback_t) (const MQTT::Publish &)

Public Member Functions
	PubSubClient (Client &c)
	Simple constructor. More...
	PubSubClient (Client &c, IPAddress &ip, uint16_t port=1883)
	Constructor with the server ip address.
	PubSubClient (Client &c, String hostname, uint16_t port=1883)
	Constructors with the host name.
PubSubClient &	set_server (IPAddress &ip, uint16_t port=1883)
	Set the server ip address.
PubSubClient &	set_server (String hostname, uint16_t port=1883)
	Set the server host name.
callback_t	callback (void) const
	Get the callback function.
PubSubClient &	set_callback (callback_t cb)
	Set the callback function.
PubSubClient &	unset_callback (void)
	Unset the callback function.
PubSubClient &	set_max_retries (uint8_t mr)
	Set the maximum number of retries when waiting for response packets.
bool	connect (String id)
	Connect to the server with a client id. More...
bool	connect (String id, String willTopic, uint8_t willQos, bool willRetain, String willMessage)
	Connect to the server with a client id and "will" parameters. More...
void	disconnect (void)
	Disconnect from the server.
bool	publish (String topic, String payload)
	Publish a string payload. More...
bool	publish (String topic, const uint8_t *payload, uint32_t plength, bool retained=false)
	Publish an arbitrary data payload. More...
bool	publish (String topic, MQTT::payload_callback_t pcb, uint32_t length, bool retained=false)
	Publish an arbitrary data payload from a callback. More...
bool	publish_P (String topic, PGM_P payload, uint32_t plength, bool retained=false)
	Publish an arbitrary data payload stored in "program" memory. More...
bool	subscribe (String topic, uint8_t qos=0)
	Subscribe to a topic. More...
bool	unsubscribe (String topic)
	Unsubscribe from a topic.
bool	loop ()
	Wait for packets to come in, processing them. More...
bool	connected ()
	Are we connected?
bool	connect (MQTT::Connect &conn)
	Connect with a pre-constructed MQTT message object.
bool	publish (MQTT::Publish &pub)
	Publish with a pre-constructed MQTT message object.
bool	subscribe (MQTT::Subscribe &sub)
	Subscribe with a pre-constructed MQTT message object.
bool	unsubscribe (MQTT::Unsubscribe &unsub)
	Unsubscribe with a pre-constructed MQTT message object.

Detailed Description

Main do-everything class that sketches will use.

Constructor & Destructor Documentation

PubSubClient::PubSubClient

(

Client &

c

)

Simple constructor.

Use set_server() before connect()

Member Function Documentation

bool PubSubClient::connect

(

String

id

)

Connect to the server with a client id.

Parameters

id	Client id for this device

bool PubSubClient::connect	(	String	id,
		String	willTopic,
		uint8_t	willQos,
		bool	willRetain,
		String	willMessage
	)

Connect to the server with a client id and "will" parameters.

The "will" is a message that is published when this client unexpectantly disconnects from the broker i.e without sending a DISCONNECT message.

Parameters

id	Client id for this device
willTopic	Topic of the "will" message
willQos	QoS level of the "will" message
willRetain	Retain setting of the "will" message
willMessage	Content (payload) of the "will" message

bool PubSubClient::loop

(

)

Wait for packets to come in, processing them.

Also periodically pings the server

bool PubSubClient::publish	(	String	topic,
		String	payload
	)

Publish a string payload.

Parameters

topic	Topic of the message
payload	String text of the message

bool PubSubClient::publish	(	String	topic,
		const uint8_t *	payload,
		uint32_t	plength,
		bool	retained = false
	)

Publish an arbitrary data payload.

Parameters

topic	Topic of the message
payload	Pointer to contents of the message
plength	Length of the message (pointed to by payload) in bytes
retained	If true, this message will be stored on the server and supplied to any future subscribers whose subscriptions match its topic name.

bool PubSubClient::publish	(	String	topic,
		MQTT::payload_callback_t	pcb,
		uint32_t	length,
		bool	retained = false
	)

Publish an arbitrary data payload from a callback.

Parameters

topic	Topic of this message
pcb	A callback function that writes the payload directly to the network Client object
length	The length of the data that 'pcb' will send

bool PubSubClient::publish_P	(	String	topic,
		PGM_P	payload,
		uint32_t	plength,
		bool	retained = false
	)

Publish an arbitrary data payload stored in "program" memory.

Parameters

topic	Topic of the message
payload	Pointer to contents of the message, stored in "program" memory
plength	Length of the message (pointed to by payload) in bytes
retained	If true, this message will be stored on the server and supplied to any future subscribers whose subscriptions match its topic name.

bool PubSubClient::subscribe	(	String	topic,
		uint8_t	qos = 0
	)

Subscribe to a topic.

Parameters

topic	Topic filter
qos	QoS value. 0 => no handshake, 1 => single handshake, 2 => two-way handshake

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

• PubSubClient.h
• PubSubClient.cpp