class QMqttSubscription

The QMqttSubscription class receives notifications from an MQTT broker about a specified topic. More…

Synopsis

Properties

• qosᅟ - This property holds the QoS level at which the subscription has been made

• reasonᅟ - This property holds the reason string for the subscription

• reasonCodeᅟ - This property holds the reason code for the subscription

• sharedSubscriptionᅟ - This property holds whether the subscription is shared

• sharedSubscriptionNameᅟ - This property holds the name of the shared subscription

• stateᅟ - This property holds the state of the subscription

• topicᅟ - This property holds the topic of the subscription

Methods

• def isSharedSubscription()

• def qos()

• def reason()

• def reasonCode()

• def sharedSubscriptionName()

• def state()

• def topic()

• def userProperties()

Slots

• def unsubscribe()

Signals

• def messageReceived()

• def qosChanged()

• def stateChanged()

Note

This documentation may contain snippets that were automatically translated from C++ to Python. We always welcome contributions to the snippet translation. If you see an issue with the translation, you can also let us know by creating a ticket on https:/bugreports.qt.io/projects/PYSIDE

Detailed Description

class SubscriptionState

This enum type describes the states a subscription can have.

Constant	Description
QMqttSubscription.Unsubscribed	The topic has been unsubscribed from.
QMqttSubscription.SubscriptionPending	A request for a subscription has been sent, but is has not been confirmed by the broker yet.
QMqttSubscription.Subscribed	The subscription was successful and messages will be received.
QMqttSubscription.UnsubscriptionPending	A request to unsubscribe from a topic has been sent, but it has not been confirmed by the broker yet.
QMqttSubscription.Error	An error occured.

Note

Properties can be used directly when from __feature__ import true_property is used or via accessor functions otherwise.

property qosᅟ: int

This property holds This property holds the QoS level at which the subscription has been made..

The QoS level of the subscription specifies the maximum QoS level at which the client will receive messages. The publisher can still send messages at a lower level.

Access functions:

• qos()

• Signal qosChanged()

property reasonᅟ: str

This property holds This property holds the reason string for the subscription..

A reason string is used by the server to provide additional information about the subscription. It is optional for the server to send it.

Access functions:

• reason()

property reasonCodeᅟ: QMqtt.ReasonCode

This property holds This property holds the reason code for the subscription..

The reason code specifies the error type if a subscription has failed, or the level of QoS for success.

Access functions:

• reasonCode()

property sharedSubscriptionᅟ: bool

This property holds This property holds whether the subscription is shared..

Access functions:

• isSharedSubscription()

property sharedSubscriptionNameᅟ: str

This property holds This property holds the name of the shared subscription..

Access functions:

• sharedSubscriptionName()

property stateᅟ: QMqttSubscription.SubscriptionState

This property holds This property holds the state of the subscription..

Access functions:

• state()

• Signal stateChanged()

property topicᅟ: QMqttTopicFilter

This property holds This property holds the topic of the subscription..

Access functions:

• topic()

isSharedSubscription()

Return type:

bool

Getter of property sharedSubscriptionᅟ .

messageReceived(msg)

Parameters:

msg – QMqttMessage

This signal is emitted when the new message msg has been received.

qos()

Return type:

int

Getter of property qosᅟ .

qosChanged(arg__1)

Parameters:

arg__1 – int

Notification signal of property qosᅟ .

reason()

Return type:

str

Getter of property reasonᅟ .

reasonCode()

Return type:

ReasonCode

Getter of property reasonCodeᅟ .

sharedSubscriptionName()

Return type:

str

Getter of property sharedSubscriptionNameᅟ .

state()

Return type:

SubscriptionState

Getter of property stateᅟ .

stateChanged(state)

Parameters:

state – SubscriptionState

Notification signal of property stateᅟ .

topic()

Return type:

QMqttTopicFilter

Getter of property topicᅟ .

unsubscribe()

Unsubscribes from topic .

Note

This might affect all shared pointer instances returned by subscribe() .

userProperties()

Return type:

QMqttUserProperties

Returns the user properties received from the broker when the subscription has been accepted.

Note

This function will only provide valid data when the client specifies MQTT_5_0 as ProtocolVersion .