Enum MqttError 

pub enum MqttError {
    Io(String),
    InvalidTopicName(String),
    InvalidTopicFilter(String),
    InvalidClientId(String),
    ConnectionError(String),
    ConnectionRefused(ReasonCode),
    ProtocolError(String),
    MalformedPacket(String),
    PacketTooLarge {
        size: usize,
        max: usize,
    },
    AuthenticationFailed,
    NotAuthorized,
    NotConnected,
    AlreadyConnected,
    Timeout,
    SubscriptionFailed(ReasonCode),
    UnsubscriptionFailed(ReasonCode),
    PublishFailed(ReasonCode),
    PacketIdNotFound(u16),
    PacketIdInUse(u16),
    InvalidQoS(u8),
    InvalidPacketType(u8),
    InvalidReasonCode(u8),
    InvalidPropertyId(u8),
    DuplicatePropertyId(u8),
    SessionExpired,
    KeepAliveTimeout,
    ServerShuttingDown,
    ClientClosed,
    ConnectionClosedByPeer,
    MaxConnectTime,
    TopicAliasInvalid(u16),
    ReceiveMaximumExceeded,
    WillRejected,
    ImplementationSpecific(String),
    UnsupportedProtocolVersion,
    InvalidState(String),
    ClientIdentifierNotValid,
    BadUsernameOrPassword,
    ServerUnavailable,
    ServerBusy,
    Banned,
    BadAuthenticationMethod,
    QuotaExceeded,
    PayloadFormatInvalid,
    RetainNotSupported,
    QoSNotSupported,
    UseAnotherServer,
    ServerMoved,
    SharedSubscriptionsNotSupported,
    ConnectionRateExceeded,
    SubscriptionIdentifiersNotSupported,
    WildcardSubscriptionsNotSupported,
    MessageTooLarge,
    FlowControlExceeded,
    PacketIdExhausted,
    StringTooLong(usize),
    Configuration(String),
}

MQTT protocol errors

This enum provides specific error variants for all possible MQTT protocol errors, validation failures, and operational issues.

Error Categories

• I/O and Network: Io, ConnectionError, Timeout, NotConnected
• Validation: InvalidTopicName, InvalidTopicFilter, InvalidClientId
• Protocol: ProtocolError, MalformedPacket, InvalidPacketType
• Authentication: AuthenticationFailed, NotAuthorized, BadUsernameOrPassword
• Operations: SubscriptionFailed, PublishFailed, UnsubscriptionFailed
• Server Status: ServerUnavailable, ServerBusy, ServerShuttingDown
• Flow Control: ReceiveMaximumExceeded, FlowControlExceeded, PacketIdExhausted

Examples

use mqtt5_protocol::{MqttError, Result};

fn validate_topic(topic: &str) -> Result<()> {
    if topic.contains('#') && !topic.ends_with('#') {
        return Err(MqttError::InvalidTopicName(
            "# wildcard must be at the end".to_string()
        ));
    }
    Ok(())
}

Variants

Io(String)

InvalidTopicName(String)

InvalidTopicFilter(String)

InvalidClientId(String)

ConnectionError(String)

ConnectionRefused(ReasonCode)

ProtocolError(String)

MalformedPacket(String)

PacketTooLarge

Fields

size: usize

max: usize

AuthenticationFailed

NotAuthorized

NotConnected

AlreadyConnected

Timeout

SubscriptionFailed(ReasonCode)

UnsubscriptionFailed(ReasonCode)

PublishFailed(ReasonCode)

PacketIdNotFound(u16)

PacketIdInUse(u16)

InvalidQoS(u8)

InvalidPacketType(u8)

InvalidReasonCode(u8)

InvalidPropertyId(u8)

DuplicatePropertyId(u8)

SessionExpired

KeepAliveTimeout

ServerShuttingDown

ClientClosed

ConnectionClosedByPeer

MaxConnectTime

TopicAliasInvalid(u16)

ReceiveMaximumExceeded

WillRejected

ImplementationSpecific(String)

UnsupportedProtocolVersion

InvalidState(String)

ClientIdentifierNotValid

BadUsernameOrPassword

ServerUnavailable

ServerBusy

Banned

BadAuthenticationMethod

QuotaExceeded

PayloadFormatInvalid

RetainNotSupported

QoSNotSupported

UseAnotherServer

ServerMoved

SharedSubscriptionsNotSupported

ConnectionRateExceeded

SubscriptionIdentifiersNotSupported

WildcardSubscriptionsNotSupported

MessageTooLarge

FlowControlExceeded

PacketIdExhausted

StringTooLong(usize)

Configuration(String)

Implementations

impl MqttError

pub fn is_normal_disconnect(&self) -> bool

Trait Implementations

impl Clone for MqttError

fn clone(&self) -> MqttError

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MqttError

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Display for MqttError

fn fmt(&self, __formatter: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Error for MqttError

fn source(&self) -> Option<&(dyn Error + 'static)>

Returns the lower-level source of this error, if any.

fn description(&self) -> &str

👎Deprecated since 1.42.0: use the Display impl or to_string()

fn cause(&self) -> Option<&dyn Error>

👎Deprecated since 1.33.0: replaced by Error::source, which can support downcasting

fn provide<'a>(&'a self, request: &mut Request<'a>)

🔬This is a nightly-only experimental API. (error_generic_member_access)

Provides type-based access to context intended for error reports.

impl From<&str> for MqttError

fn from(msg: &str) -> Self

Converts to this type from the input type.

impl From<Error> for MqttError

fn from(err: Error) -> Self

Converts to this type from the input type.

impl From<String> for MqttError

fn from(msg: String) -> Self

Converts to this type from the input type.