Struct Client

pub struct Client { /* private fields */ }

A high-level, asynchronous mosquitto MQTT client

Implementations

impl Client

pub fn with_id(id: &str, clean_session: bool) -> Result<Self, Error>

Create a new client instance with the specified id. If clean_session is true, instructs the broker to clean all messages and subscriptions on disconnect. Otherwise it will preserve them.

pub fn with_auto_id() -> Result<Self, Error>

Create a new client instance with a random client id

pub fn set_username_and_password( &self, username: Option<&str>, password: Option<&str>, ) -> Result<(), Error>

Configure the client with an optional username and password. The default is None for both. Whether you need to configure these credentials depends on the broker configuration.

pub async fn connect( &self, host: &str, port: c_int, keep_alive_interval: Duration, bind_address: Option<&str>, ) -> Result<ConnectionStatus, Error>

Connect to the broker on the specified host and port. port is typically 1883 for mqtt, but it may be different in your environment.

keep_alive_interval specifies the interval at which keepalive requests are sent. mosquitto has a minimum value of 5 seconds for this and will generate an error if you use a smaller value.

bind_address can be used to specify the outgoing interface for the connection.

connect completes when the broker acknowledges the CONNECT command.

Yields the connection return code; if the status was rejected, then an Error::RejectedConnection() variant will be returned so that you don’t have to manually check the success.

pub async fn publish<T: AsRef<str>, P: AsRef<[u8]>>( &self, topic: T, payload: P, qos: QoS, retain: bool, ) -> Result<MessageId, Error>

Publish a message to the specified topic.

The payload size can be 0-283, 435 or 455 bytes; other values will generate an error result.

retain will set the message to be retained by the broker, and delivered to new subscribers.

Returns the assigned MessageId value for the publish.

pub fn set_last_will<T: AsRef<str>, P: AsRef<[u8]>>( &self, topic: T, payload: P, qos: QoS, retain: bool, ) -> Result<(), Error>

Configure will information for a mosquitto instance. By default, clients do not have a will. This must be called before calling connect.

The payload size can be 0-283, 435 or 455 bytes; other values will generate an error result.

retain will set the message to be retained by the broker, and delivered to new subscribers.

pub fn clear_last_will(&self) -> Result<(), Error>

Remove a previously configured will. This must be called before calling connect

pub fn subscriber(&self) -> Option<Receiver<Event>>

Returns a channel that yields messages from topics that this client has subscribed to. This method can be called only once; the first time it returns the channel and subsequently it no longer has the channel receiver to retur, so will yield None.

pub async fn subscribe(&self, pattern: &str, qos: QoS) -> Result<(), Error>

Establish a subscription to topics matching pattern. The messages will be delivered via the channel returned via the subscriber method.

pub async fn unsubscribe(&self, pattern: &str) -> Result<(), Error>

Remove subscription(s) for topics that match pattern.

pub fn set_option(&self, option: &ClientOption<'_>) -> Result<(), Error>

Set an option for the client. Most options need to be set prior to calling connect in order to have any effect.

pub fn configure_tls<CAFILE, CAPATH, CERTFILE, KEYFILE>( &self, ca_file: Option<CAFILE>, ca_path: Option<CAPATH>, cert_file: Option<CERTFILE>, key_file: Option<KEYFILE>, pw_callback: Option<PasswdCallback>, ) -> Result<(), Error>

where CAFILE: AsRef<Path>, CAPATH: AsRef<Path>, CERTFILE: AsRef<Path>, KEYFILE: AsRef<Path>,

Configures the TLS parameters for the client.

ca_file is the path to a PEM encoded trust CA certificate file. Either ca_file or ca_path must be set.

ca_path is the path to a directory containing PEM encoded trust CA certificates. Either ca_file or ca_path must be set.

cert_file path to a file containing the PEM encoded certificate file for this client. If None then key_file must also be None and no client certificate will be used.

key_file path to a file containing the PEM encoded private key for this client. If None them cert_file must also be None and no client certificate will be used.

pw_callback allows you to provide a password to decrypt an encrypted key file. Specify None if the key file isn’t password protected.

pub fn set_reconnect_delay( &self, reconnect_delay: Duration, max_reconnect_delay: Duration, use_exponential_backoff: bool, ) -> Result<(), Error>

Controls reconnection behavior when running in the message loop. By default, if a client is unexpectedly disconnected, mosquitto will try to reconnect. The default reconnect parameters are to retry once per second to reconnect.

You change adjust the delay between connection attempts by changing the parameters with this function.

reconnect_delay is the base delay amount.

If use_exponential_backoff is true, then the delay is doubled on each successive attempt, until the max_reconnect_delay is reached.

If use_exponential_backoff is false, then the reconnect_delay is added on each successive attempt, until the max_reconnect_delay is reached.

Trait Implementations

impl Clone for Client

fn clone(&self) -> Client

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.