pub enum Error {
Transport(TransportError),
Protocol(ProtocolError),
Application(ApplicationError),
User(Box<dyn Error + Sync + Send>),
}
Expand description
Error type returned by all runtime library functions.
thrift::Error
is used throughout this crate as well as in auto-generated
Rust code. It consists of four variants defined by convention across Thrift
implementations:
Transport
: errors encountered while operating on I/O channelsProtocol
: errors encountered during runtime-library processingApplication
: errors encountered within auto-generated codeUser
: IDL-defined exception structs
The Application
variant also functions as a catch-all: all handler errors
are automatically turned into application errors.
All error variants except Error::User
take an eponymous struct with two
required fields:
kind
: variant-specific enum identifying the error sub-typemessage
: human-readable error info string
kind
is defined by convention while message
is freeform. If none of the
enumerated kinds are suitable use Unknown
.
To simplify error creation convenience constructors are defined for all
variants, and conversions from their structs (thrift::TransportError
,
thrift::ProtocolError
and thrift::ApplicationError
into thrift::Error
.
§Examples
Create a TransportError
.
use thrift::{TransportError, TransportErrorKind};
// explicit
let err0: thrift::Result<()> = Err(
thrift::Error::Transport(
TransportError {
kind: TransportErrorKind::TimedOut,
message: format!("connection to server timed out")
}
)
);
// use conversion
let err1: thrift::Result<()> = Err(
thrift::Error::from(
TransportError {
kind: TransportErrorKind::TimedOut,
message: format!("connection to server timed out")
}
)
);
// use struct constructor
let err2: thrift::Result<()> = Err(
thrift::Error::Transport(
TransportError::new(
TransportErrorKind::TimedOut,
"connection to server timed out"
)
)
);
// use error variant constructor
let err3: thrift::Result<()> = Err(
thrift::new_transport_error(
TransportErrorKind::TimedOut,
"connection to server timed out"
)
);
Create an error from a string.
use thrift::{ApplicationError, ApplicationErrorKind};
// we just use `From::from` to convert a `String` into a `thrift::Error`
let err0: thrift::Result<()> = Err(
thrift::Error::from("This is an error")
);
// err0 is equivalent to...
let err1: thrift::Result<()> = Err(
thrift::Error::Application(
ApplicationError {
kind: ApplicationErrorKind::Unknown,
message: format!("This is an error")
}
)
);
Return an IDL-defined exception.
// Thrift IDL exception definition.
exception Xception {
1: i32 errorCode,
2: string message
}
use std::error::Error;
use std::fmt;
use std::fmt::{Display, Formatter};
// auto-generated by the Thrift compiler
#[derive(Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
pub struct Xception {
pub error_code: Option<i32>,
pub message: Option<String>,
}
// auto-generated by the Thrift compiler
impl Error for Xception { }
// auto-generated by the Thrift compiler
impl From<Xception> for thrift::Error {
fn from(e: Xception) -> Self {
thrift::Error::User(Box::new(e))
}
}
// auto-generated by the Thrift compiler
impl Display for Xception {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
write!(f, "remote service threw Xception")
}
}
// in user code...
let err: thrift::Result<()> = Err(
thrift::Error::from(Xception { error_code: Some(1), message: None })
);
Variants§
Transport(TransportError)
Errors encountered while operating on I/O channels.
These include connection closed and bind failure.
Protocol(ProtocolError)
Errors encountered during runtime-library processing.
These include message too large and unsupported protocol version.
Application(ApplicationError)
Errors encountered within auto-generated code, or when incoming or outgoing messages violate the Thrift spec.
These include out-of-order messages and missing required struct fields.
This variant also functions as a catch-all: errors from handler
functions are automatically returned as an ApplicationError
.
User(Box<dyn Error + Sync + Send>)
IDL-defined exception structs.
Implementations§
source§impl Error
impl Error
sourcepub fn read_application_error_from_in_protocol(
i: &mut dyn TInputProtocol,
) -> Result<ApplicationError>
pub fn read_application_error_from_in_protocol( i: &mut dyn TInputProtocol, ) -> Result<ApplicationError>
Create an ApplicationError
from its wire representation.
Application code should never call this method directly.
sourcepub fn write_application_error_to_out_protocol(
e: &ApplicationError,
o: &mut dyn TOutputProtocol,
) -> Result<()>
pub fn write_application_error_to_out_protocol( e: &ApplicationError, o: &mut dyn TOutputProtocol, ) -> Result<()>
Convert an ApplicationError
into its wire representation and write
it to the remote.
Application code should never call this method directly.