Functions#

This section provides a reference to the MQTT API functions.

Functions#

sl_status_t
sl_mqtt_client_init(sl_mqtt_client_t *client, sl_mqtt_client_event_handler event_handler)

Initialize the mqtt_client and registers the event_handler.

sl_status_t
sl_mqtt_client_deinit(sl_mqtt_client_t *client)

Deinitialize the MQTT client.

sl_status_t
sl_mqtt_client_connect(sl_mqtt_client_t *client, const sl_mqtt_broker_t *broker, const sl_mqtt_client_last_will_message_t *last_will_message, const sl_mqtt_client_configuration_t *configuration, uint32_t timeout)

Connect the client to MQTT broker.

sl_status_t
sl_mqtt_client_disconnect(sl_mqtt_client_t *client, uint32_t timeout)

Disconnect the client from MQTT broker.

sl_status_t
sl_mqtt_client_publish(sl_mqtt_client_t *client, const sl_mqtt_client_message_t *message, uint32_t timeout, void *context)

Publish a message.

sl_status_t
sl_mqtt_client_subscribe(sl_mqtt_client_t *client, const uint8_t *topic, uint16_t topic_length, sl_mqtt_qos_t qos_level, uint32_t timeout, sl_mqtt_client_message_received message_handler, void *context)

Indicate which client can subscribe to a topic.

sl_status_t
sl_mqtt_client_unsubscribe(sl_mqtt_client_t *client, const uint8_t *topic, uint16_t length, uint32_t timeout, void *context)

Indicate which client can unsubscribe a topic.

Function Documentation#

sl_mqtt_client_init#

sl_status_t sl_mqtt_client_init (sl_mqtt_client_t * client, sl_mqtt_client_event_handler event_handler)

Initialize the mqtt_client and registers the event_handler.

Parameters
[in]client

Valid pointer to the client structure. This shall not be null.

[in]event_handler

Event handler which will be called for various events on client.

Returns


Definition at line 38 of file components/service/mqtt/inc/sl_mqtt_client.h

sl_mqtt_client_deinit#

sl_status_t sl_mqtt_client_deinit (sl_mqtt_client_t * client)

Deinitialize the MQTT client.

Parameters
[in]client

Valid pointer to the client structure.

Returns


Definition at line 50 of file components/service/mqtt/inc/sl_mqtt_client.h

sl_mqtt_client_connect#

sl_status_t sl_mqtt_client_connect (sl_mqtt_client_t * client, const sl_mqtt_broker_t * broker, const sl_mqtt_client_last_will_message_t * last_will_message, const sl_mqtt_client_configuration_t * configuration, uint32_t timeout)

Connect the client to MQTT broker.

Parameters
[in]client

Client which would be connected to the broker.

[in]broker

Broker configuration.

[in]last_will_message

Last will message of the client.

[in]configuration

Client configuration.

[in]timeout

Timeout for the API. If the value is zero, the API will be asynchronous.

Returns

  • sl_status_t. If called asynchronously, SL_STATUS_IN_PROGRESS will be returned as status.

Note

    1. In subsequent calls to connect, it is optional to provide broker, last_will_message, and configuration parameters.

    2. If broker and configuration parameters are given null, then value given in the first connect() call would be retained.

    3. In case of last_will_message parameter, values given in each connect() call would be considered. If value of last_will_message parameter is given as null, then no will message would be sent to the broker parameter.

    4. Only is_clean_session, credential_id, client_id, client_id_length of sl_mqtt_client_configuration_t are considered.


Definition at line 75 of file components/service/mqtt/inc/sl_mqtt_client.h

sl_mqtt_client_disconnect#

sl_status_t sl_mqtt_client_disconnect (sl_mqtt_client_t * client, uint32_t timeout)

Disconnect the client from MQTT broker.

Parameters
[in]client

Client which needs to be disconnected from the broker.

[in]timeout

Timeout for the API. If the value is zero, the API will be asynchronous.

Returns

  • sl_status_t. If called asynchronously, SL_STATUS_IN_PROGRESS will be returned as status.


Definition at line 93 of file components/service/mqtt/inc/sl_mqtt_client.h

sl_mqtt_client_publish#

sl_status_t sl_mqtt_client_publish (sl_mqtt_client_t * client, const sl_mqtt_client_message_t * message, uint32_t timeout, void * context)

Publish a message.

Parameters
[in]client

Client which requires to publish the message.

[in]message

Message which needs to be published.

[in]timeout

Timeout for the API. If the value is zero, the API will be asynchronous.

[in]context

Context which would be returned in event handler if the API is called asynchronously. The caller must ensure that the lifecycle of context is retained until the callback is invoked. The deallocation of context is also the responsibility of the caller.

Returns

  • sl_status_t. If called asynchronously, SL_STATUS_IN_PROGRESS will be returned as status.


Definition at line 111 of file components/service/mqtt/inc/sl_mqtt_client.h

sl_mqtt_client_subscribe#

sl_status_t sl_mqtt_client_subscribe (sl_mqtt_client_t * client, const uint8_t * topic, uint16_t topic_length, sl_mqtt_qos_t qos_level, uint32_t timeout, sl_mqtt_client_message_received message_handler, void * context)

Indicate which client can subscribe to a topic.

Parameters
[in]client

Client which needs to subscribe to the topic.

[in]topic

Topic of interest.

[in]topic_length

Length of the topic.

[in]qos_level

Quality of service using which client subscribes.

[in]timeout

Timeout for API. If the value is zero, the API will be asynchronous.

[in]message_handler

Message handler which invokes for messages published on the topic.

[in]context

Context that is sent back to the message handler. The caller must ensure that the lifecycle of the context is retained until the callback is invoked. The deallocation of context is also the responsibility of the caller.

Returns

  • sl_status_t. If called asynchronously, SL_STATUS_IN_PROGRESS will be returned as status.


Definition at line 138 of file components/service/mqtt/inc/sl_mqtt_client.h

sl_mqtt_client_unsubscribe#

sl_status_t sl_mqtt_client_unsubscribe (sl_mqtt_client_t * client, const uint8_t * topic, uint16_t length, uint32_t timeout, void * context)

Indicate which client can unsubscribe a topic.

Parameters
[in]client

Client that unsubscribes the topic.

[in]topic

Topic from which client needs to unsubscribe.

[in]length

Length of the topic.

[in]timeout

Timeout for the API. If the value is zero, the API will be asynchronous.

[in]context

Context that returns in event handler if the API is called asynchronously. The caller must ensure that the lifecycle of the context is retained until the callback is invoked. The deallocation of context is also the responsibility of the caller.

Returns

  • sl_status_t. If called asynchronously, SL_STATUS_IN_PROGRESS will be returned as status.


Definition at line 164 of file components/service/mqtt/inc/sl_mqtt_client.h