Enum Error 

#[non_exhaustive]
pub enum Error {
    Rejected(Rejection),
    BatchRejected {
        index: usize,
        rejection: Rejection,
    },
    Value(ValueError),
    Amount(AmountError),
    Query(QueryError),
    Transparency(Error),
    Integrity(IntegrityError),
    Backend(BackendError),
    Config(ConfigError),
}

Everything a ledger operation can fail with.

use doubleentry::{Error, Rejection};

let error = Error::from(Rejection::TooFewPostings { count: 1 });
assert_eq!(error.rejection().map(Rejection::code), Some(101));
assert!(!error.is_transient());
assert_eq!(error.to_string(), "rejected: [101] an entry needs at least two postings, found 1");

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Rejected(Rejection)

The ledger refused the input. Final for this input: do not retry it unchanged.

BatchRejected

The ledger refused draft index of an atomic batch (Journal::record_batch); nothing of the batch was recorded. Final for this batch: do not retry it unchanged.

Fields

index: usize

The refused draft’s index in the batch.

rejection: Rejection

Why it was refused.

Value(ValueError)

A standalone value constructor failed. Never returned by a ledger operation: a malformed draft is Error::Rejected.

Amount(AmountError)

Money parsing or arithmetic failed. Never returned by a ledger operation.

Query(QueryError)

A read asked an impossible question.

Transparency(Error)

A transparency artefact — a note, checkpoint, cosignature, policy, proof, bundle or verifier step — was refused. Final for this input.

Integrity(IntegrityError)

The ledger’s own stored data fails verification. Never retry; investigate.

Backend(BackendError)

The backend failed. See is_transient and may_have_applied.

Config(ConfigError)

The store holds another ledger, this ledger at another scale, or a database of another schema: a configuration mistake (a wrong URL, schema name, ledger id or P), not damaged data. Nothing was read or changed; fix the configuration.

Implementations

impl Error

pub fn is_transient(&self) -> bool

Whether retrying the same operation may succeed: only a transient backend failure.

pub fn may_have_applied(&self) -> bool

Whether the operation may have been applied although it failed: only a backend failure whose outcome is unknown. Retry with the same draft — idempotency makes the retry safe.

pub fn code(&self) -> Option<u16>

The stable rejection code, when the ledger refused the input — the number an HTTP handler or a log line keys on.

use doubleentry::{Error, Rejection};

let error = Error::from(Rejection::TooFewPostings { count: 1 });
assert_eq!(error.code(), Some(101));
assert_eq!(format!("{error:?}"), "rejected: [101] an entry needs at least two postings, found 1");

pub fn rejection(&self) -> Option<&Rejection>

The rejection, when the ledger refused the input (a single operation or a draft of a batch).

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

The same line as Display — rejected: [427] … — so a main returning this error prints its code and message; {:#?} shows the structure.

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

Formats the value using the given formatter.

impl Display for Error

One line — rejected: …, query: …, integrity failure at position 7: … — honouring width, fill and alignment and never cut short.

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 From<AmountError> for Error

fn from(error: AmountError) -> Self

Converts to this type from the input type.

impl From<AuditFailure> for Error

fn from(failure: AuditFailure) -> Self

Converts to this type from the input type.

impl From<BackendError> for Error

fn from(error: BackendError) -> Self

Converts to this type from the input type.

impl From<BuildError> for Error

fn from(error: BuildError) -> Self

The stage-1 Rejection a draft with this deferred error gets from record.

impl From<ConfigError> for Error

fn from(error: ConfigError) -> Self

Converts to this type from the input type.

impl From<DecodeError> for Error

fn from(error: DecodeError) -> Self

Proven bytes that do not decode: transparency::Error::Decode.

impl From<Error> for Error

fn from(error: Error) -> Self

Converts to this type from the input type.

impl From<IntegrityError> for Error

fn from(error: IntegrityError) -> Self

Converts to this type from the input type.

impl From<ProofError> for Error

fn from(error: ProofError) -> Self

A proof that does not verify: transparency::Error::Proof.

impl From<QueryError> for Error

fn from(error: QueryError) -> Self

Converts to this type from the input type.

impl From<Rejection> for Error

fn from(rejection: Rejection) -> Self

Converts to this type from the input type.

impl From<SealOrderError> for Error

fn from(error: SealOrderError) -> Self

A seal that does not follow its predecessor: transparency::Error::SealOrder.

impl From<StoreError> for Error

fn from(error: StoreError) -> Self

Integrity is stored data the ledger cannot trust (Error::Integrity); SchemaMismatch and LedgerMismatch are a store configured for something else (Error::Config); everything else is a BackendError keeping both flags, with the store error as its source.

impl From<ValueError> for Error

fn from(error: ValueError) -> Self

Converts to this type from the input type.