Enum Error 

pub enum Error {
    InvalidConnectReturnCode(u8),
    InvalidPacketType(u8),
    InvalidProtocolLevel(u8),
    InvalidProtocolName(String),
    InvalidProperty(u8),
    InvalidQos(u8),
    InvalidReasonCode(u8),
    InvalidRetainHandling(u8),
    InvalidTopicName(String),
    InvalidTopicFilter(String),
    InvalidUtf8,
    Io(Error),
    MalformedVariableByteInteger,
    MalformedPacket,
    NoCodes,
    NotEnoughBytes(usize),
    NoTopic,
    OutgoingPayloadSizeLimitExceeded(usize),
    OutOfBounds,
    PayloadTooLarge,
    PayloadRequired,
    PayloadSizeLimitExceeded(usize),
    ProtocolError,
    ProtocolMismatch,
    ProtocolNotSupported,
    PropertyMismatch,
    StringTooLong,
}

Represents errors that can occur when working with the MQTT protocol.

Each variant includes a descriptive error message and, where applicable, additional context (e.g., invalid values or sizes). This enum implements the standard Error trait and can be easily converted from other error types.

Variants

InvalidConnectReturnCode(u8)

Indicates an invalid connect return code received from the broker.

InvalidPacketType(u8)

Indicates an invalid packet type encountered during parsing.

InvalidProtocolLevel(u8)

Indicates an unsupported or invalid protocol level.

InvalidProtocolName(String)

Indicates an invalid or unrecognized protocol name.

InvalidProperty(u8)

Indicates an invalid property identifier in MQTT properties.

InvalidQos(u8)

Indicates an invalid Quality of Service level.

InvalidReasonCode(u8)

Indicates an invalid reason code in MQTT response packets.

InvalidRetainHandling(u8)

Indicates invalid retain handling configuration.

InvalidTopicName(String)

Indicates a malformed or invalid topic name.

InvalidTopicFilter(String)

Indicates a malformed or invalid topic filter.

InvalidUtf8

Indicates invalid UTF-8 data in string fields.

Io(Error)

Wraps an I/O error that occurred during network operations.

MalformedVariableByteInteger

Indicates a malformed variable byte integer encoding.

MalformedPacket

Indicates a general malformed packet structure.

NoCodes

Indicates that the payload must contain at least one return code but was empty.

NotEnoughBytes(usize)

Indicates insufficient bytes to complete packet framing.

NoTopic

Indicates that the payload must contain at least one topic filter but was empty.

OutgoingPayloadSizeLimitExceeded(usize)

Indicates that the outgoing payload exceeds the configured size limit.

OutOfBounds

Indicates an out-of-bounds access during packet parsing.

PayloadTooLarge

Indicates that the payload exceeds the maximum allowed size.

PayloadRequired

Indicates that a payload is required for this packet type but was missing.

PayloadSizeLimitExceeded(usize)

Indicates that the payload exceeds the general size limit.

ProtocolError

Indicates a general protocol violation error.

ProtocolMismatch

Indicates a mismatch between expected and actual protocol versions.

ProtocolNotSupported

Indicates that the requested protocol is not supported.

PropertyMismatch

Indicates a mismatch between expected and actual properties.

StringTooLong

Indicates that a string exceeds the maximum allowed length.

Trait Implementations

impl Debug for Error

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

Formats the value using the given formatter.

impl Display for Error

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

Formats the value using the given formatter.

impl Error for Error

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<Error> for Error

fn from(source: Error) -> Self

Converts to this type from the input type.