3.2.8.7.2 MQTT System Service Interface

This section describes the MQTT System Service Interface

MQTT service status enum
MQTT event enum
MQTT message configuration struct
MQTT message enum
MQTT QoS enum
MQTT publish retain enum
MQTT frame struct
MQTT LWT configuration struct

MQTT Service Status Enum

States involved in the operation of the MQTT state machine.

typedef enum 
{
    SYS_RNWF_MQTT_CONFIG,               /**<Configure the MQTT Broker parameters*/
    SYS_RNWF_MQTT_CONNECT,              /**<Connect to the MQTT Broker */
    SYS_RNWF_MQTT_RECONNECT,            /**<Request reconnect to the MQTT Cloud*/
    SYS_RNWF_MQTT_DISCONNECT,           /**<Trigger Disconnect from MQTT Broker*/
    SYS_RNWF_MQTT_SUBSCRIBE_QOS,        /**<Subscribe to QoS Topics */
    SYS_RNWF_MQTT_PUBLISH,              /**<Publis to MQTT Broker*/
    SYS_RNWF_MQTT_SET_CALLBACK,         /**<Configure the MQTT Application Callback*/              
}SYS_RNWF_MQTT_SERVICE_t;

MQTT Event Enum

Events involved in the operation of the MQTT state machine

typedef enum
{
    SYS_RNWF_MQTT_CONNECTED,    /**<Connected to MQTT broker event */
    SYS_RNWF_MQTT_DISCONNECTED, /**<Disconnected from MQTT broker event*/   
    SYS_RNWF_MQTT_SUBCRIBE_MSG,  /**<Event to report received MQTT message*/   
}SYS_RNWF_MQTT_EVENT_t;

MQTT Message Configuration Struct

Defines the configuration parameters required to establish connection with MQTT Broker

typedef struct 
{    
    /**<MQTT Broker/Server URL */    
    const char *url;          
    
    /**<MQTT Service client ID*/
    const char *clientid;
    
    /**<MQTT User Name Credential */
    const char *username;       
    
    /**<MQTT Password Credential */ 
    const char *password;       
    
    /**<MQTT Broker/Server Port */
    uint16_t port;          
    
    /*MQTT TLS Index*/
    uint8_t     tls_idx;
    
    /*Azure DPS*/
    uint8_t     azure_dps;
    
    /*TLS Configuration*/
    uint8_t     *tls_conf;    

    /*MQTT Protocol Version*/
    uint8_t     protoVer;

    /*MQTT Keep Alive time */
    uint16_t     keep_alive_time;


}SYS_RNWF_MQTT_CFG_t;

MQTT Message Enum

typedef enum
{
    SYS_RNWF_NEW_MSG,        /**New message*/ 
    SYS_RNWF_DUP_MSG         /**Duplicate message*/ 
}SYS_RNWF_MQTT_MSG_t;

MQTT QoS Enum

typedef enum
{
    SYS_RNWF_MQTT_QOS0,      /**<No-Ack, Best effort delivery(No Guarantee)*/          
    SYS_RNWF_MQTT_QOS1,      /**<Pub-Ack, sent untill PUBACK from broker(possible duplicates) */
    SYS_RNWF_MQTT_QOS2,      /**<Highest service, no duplicate with guarantee */          
}SYS_RNWF_MQTT_QOS_t;

MQTT Publish Retain Enum

Sets whether the published message is retained at the broker or not.

typedef enum
{
    SYS_RNWF_NO_RETAIN,          /**<Publish message is not saved at broker */
    SYS_RNWF_RETAIN,             /**<Publish message is saved at broker */
}SYS_RNWF_MQTT_RETAIN_t;

MQTT Frame Struct

typedef struct
{
    SYS_RNWF_MQTT_MSG_t isNew;          /**<Indicates message is new or duplicate */
    SYS_RNWF_MQTT_QOS_t qos;            /**<QoS type for the message ::RNWF_MQTT_QOS_t */
    SYS_RNWF_MQTT_RETAIN_t isRetain;    /**<Retain flag for the publish message */
    const uint8_t *topic;           /**<Publish topic for the message */
    const uint8_t *message;         /**<Indicates message is new or duplicate */               
}SYS_RNWF_MQTT_FRAME_t;

MQTT LWT Configuration Struct

typedef struct
{
    /**<QoS type for the LWT message ::SYS_RNWF_MQTT_QOS_t */
    SYS_RNWF_MQTT_QOS_t qos;
    
    /**<Retain flag for the LWT message */
    SYS_RNWF_MQTT_RETAIN_t isRetain; 
    
    /**<Topic name of the LWT message */
    const char *topic_name; 
    
    /**<LWT message */
    const char *message;
    
}SYS_RNWF_MQTT_LWT_CFG_t;