Struct Error 

pub struct Error { /* private fields */ }

Any error raised by the client, and the command it belongs to.

Match on kind to tell errors apart, and read command to know which command produced it:

if let Err(e) = result {
    if matches!(e.kind(), ErrorKind::Timeout(_)) {
        eprintln!("{:?} timed out", e.command());
    }
}

Implementations

impl Error

pub fn kind(&self) -> &ErrorKind

What the error is.

pub fn into_kind(self) -> ErrorKind

Consumes the error and yields its kind, for matching by value.

pub fn context(&self) -> Option<&ErrorContext>

The command the error belongs to, when the client knows it.

None for an error raised outside any command, such as a connection timeout.

pub fn command(&self) -> Option<&str>

The name of the command the error belongs to — shorthand for context().map(ErrorContext::command).

pub fn is_connection_error(&self) -> bool

Whether the connection to the server is what failed: the transport broke, the peer went away, or a reply could not be framed.

True for a transport or TLS failure, an end of stream, a disconnection, the loss of the network task, and a RESP framing failure — the last one because a stream the parser lost track of cannot carry another command, so the client drops the connection and reconnects. False for anything the server answered (is_server_error), for a timeout (is_timeout), and for a decode failure on a well-framed reply, which fails one command only.

The command may or may not have run: the answer, if any, was lost with the connection.

pub fn is_timeout(&self) -> bool

Whether a deadline expired before the operation completed.

Covers both Config::connect_timeout and Config::command_timeout; command tells them apart, being None for a connection that never got to send anything. A blocking command reaching its own server-side timeout is not an error at all — it replies nil, so it arrives as None.

pub fn is_server_error(&self) -> bool

Whether the server answered, and answered an error.

The connection is healthy and the command reached the server: what failed is the command itself — a wrong type, a missing script, a refused authentication. Match on RedisError::kind for the exact code.

pub fn is_retryable(&self) -> bool

Whether the failure is transient, so that sending the command again may succeed.

True for every connection error, for a timeout, and for the server codes that ask for a replay: TRYAGAIN, CLUSTERDOWN, MASTERDOWN and NOMASTERLINK.

Warning

Transient does not mean the command did not run. A connection that dies or a deadline that expires after the server applied the write leaves no way to tell it apart from one that died before. Replay only commands that are safe to apply twice, or make them idempotent first — INCR replayed on a lost reply counts twice.

Trait Implementations

impl Clone for Error

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

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, f: &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 Error for Error

fn custom<T>(msg: T) -> Self

where T: Display,

Raised when there is general error when deserializing a type.

fn invalid_type(unexp: Unexpected<'_>, exp: &dyn Expected) -> Self

Raised when a Deserialize receives a type different from what it was expecting.

fn invalid_value(unexp: Unexpected<'_>, exp: &dyn Expected) -> Self

Raised when a Deserialize receives a value of the right type but that is wrong for some other reason.

fn invalid_length(len: usize, exp: &dyn Expected) -> Self

Raised when deserializing a sequence or map and the input data contains too many or too few elements.

fn unknown_variant(variant: &str, expected: &'static [&'static str]) -> Self

Raised when a Deserialize enum type received a variant with an unrecognized name.

fn unknown_field(field: &str, expected: &'static [&'static str]) -> Self

Raised when a Deserialize struct type received a field with an unrecognized name.

fn missing_field(field: &'static str) -> Self

Raised when a Deserialize struct type expected to receive a required field with a particular name but that field was not present in the input.

fn duplicate_field(field: &'static str) -> Self

Raised when a Deserialize struct type received more than one of the same field.

impl Error for Error

fn custom<T>(msg: T) -> Self

where T: Display,

Used when a Serialize implementation encounters any error while serializing a type.

impl From<ClientError> for Error

fn from(value: ClientError) -> Self

Converts to this type from the input type.

impl From<Error> for Error

fn from(value: Error) -> Self

Converts to this type from the input type.

impl From<Error> for Error

Available on crate feature rustls only.

fn from(value: Error) -> Self

Converts to this type from the input type.

impl From<ErrorKind> for Error

fn from(kind: ErrorKind) -> Self

Converts to this type from the input type.

impl From<FromUtf8Error> for Error

fn from(value: FromUtf8Error) -> Self

Converts to this type from the input type.

impl From<InvalidDnsNameError> for Error

Available on crate feature rustls only.

fn from(value: InvalidDnsNameError) -> Self

Converts to this type from the input type.

impl From<JoinError> for Error

Available on crate feature tokio-runtime only.

fn from(value: JoinError) -> Self

Converts to this type from the input type.

impl From<ParseFloatError> for Error

fn from(value: ParseFloatError) -> Self

Converts to this type from the input type.

impl From<ParseIntError> for Error

fn from(value: ParseIntError) -> Self

Converts to this type from the input type.

impl From<RecvError> for Error

fn from(value: RecvError) -> Self

Converts to this type from the input type.

impl From<RedisError> for Error

fn from(value: RedisError) -> Self

Converts to this type from the input type.

impl From<SendError<()>> for Error

fn from(value: SendError<()>) -> Self

Converts to this type from the input type.

impl From<SendError> for Error

fn from(value: SendError) -> Self

Converts to this type from the input type.

impl From<Utf8Error> for Error

fn from(value: Utf8Error) -> Self

Converts to this type from the input type.