Enum Error 

#[non_exhaustive]
pub enum Error {
    Config(String),
    Io(Error),
    Figment(Box<Error>),
    Sqlx(Error),
    Migrate(MigrateError),
    Cbor(CborError),
    Crypto(CryptoError),
    Signing(String),
    LeaseHeld {
        instance_id: String,
        age_secs: u64,
    },
    LabelNotFound {
        src: String,
        uri: String,
        val: String,
    },
    ReportNotFound {
        id: i64,
    },
    ReportAlreadyResolved {
        id: i64,
    },
    ReasonNotFound(String),
    DurationRequiredForTempSuspension,
    DurationOnlyForTempSuspension,
    ActionNotFound(i64),
    ActionAlreadyRevoked(i64),
    SubjectUriMismatch,
    StrikeCacheMissing(String),
    PendingActionNotFound(i64),
    PendingAlreadyResolved(i64),
    SubjectTakendown(String),
}

Top-level error type for the cairn-mod library.

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.

Config(String)

Configuration loading or validation failed.

Io(Error)

I/O failure (filesystem, stdio, etc.).

Figment(Box<Error>)

Figment config-source failure (TOML parse, env-var extraction).

Sqlx(Error)

SQLx query or connection failure.

Migrate(MigrateError)

Embedded migration runner failed.

Cbor(CborError)

DAG-CBOR encode / decode failure from proto-blue-lex-cbor.

Crypto(CryptoError)

Cryptographic primitive failure (signing, hashing, key parse).

Signing(String)

Invariant violation specific to label signing (e.g. missing sig, wrong algorithm in the multibase key, sig-length mismatch).

LeaseHeld

Another Cairn instance holds a fresh lease on the same SQLite file (§F5 single-instance invariant). Refusing to start — the other instance must shut down or its lease must age past 60s.

Fields

instance_id: String

Instance identifier of the rival process holding the lease.

age_secs: u64

Seconds since that instance last heartbeated.

LabelNotFound

Negating a label that does not currently apply. Either the tuple (src, uri, val) has no apply events, or the most recent event for the tuple is already a negation (§F6).

Fields

src: String

Labeler DID (Cairn’s own service DID for emissions).

uri: String

Subject AT-URI or DID.

val: String

Label value.

ReportNotFound

resolveReport (§F12) targeted a report id that doesn’t exist. Surface via the handler as ReportNotFound (declared lexicon error).

Fields

id: i64

Report primary key that didn’t resolve.

ReportAlreadyResolved

resolveReport (§F12) targeted a report that is already resolved. Surface via the handler as InvalidRequest with a generic message (no timestamps or resolver DID per the anti-leak principle).

Fields

id: i64

Report primary key that was already resolved.

ReasonNotFound(String)

recordAction (§F20, #51) carried a reason identifier that isn’t declared in the operator’s [moderation_reasons] vocabulary. Handler surfaces this as InvalidReason (400).

DurationRequiredForTempSuspension

recordAction (§F20, #51) was called with type=temp_suspension but no duration. Handler surfaces this as DurationRequired (400). Required because expires_at on the row is computed from effective_at + duration; without one the row would silently behave as indef_suspension.

DurationOnlyForTempSuspension

recordAction (§F20, #51) was called with a non-temp_suspension type plus a duration. Handler surfaces this as DurationNotAllowed (400). Strict reject (rather than silent drop) so an operator who meant temp_suspension doesn’t end up with an indef_suspension whose duration string is lost.

ActionNotFound(i64)

revokeAction (§F20, #51) targeted a subject_actions.id that doesn’t exist. Handler surfaces this as ActionNotFound (404).

ActionAlreadyRevoked(i64)

revokeAction (§F20, #51) targeted a row whose revoked_at is already non-NULL. Handler surfaces this as ActionAlreadyRevoked (400). The schema trigger forbids re-revocation; the recorder catches it before the UPDATE for a clean lexicon error.

SubjectUriMismatch

recordAction (§F20, #51) was called with an at://-URI subject whose repo DID does not match a separate subject_did context. Reserved for future use; v1.4 derives subject_did from the URI directly so this variant is currently unreachable in practice but kept for the lexicon error surface.

StrikeCacheMissing(String)

get_or_recompute_strike_count (§F20, #55) was called with a subject_did that has no subject_strike_state row — i.e., no actions have ever been recorded against this subject. Same semantic as the SubjectNotFound lexicon error from the read endpoints; the typed variant here lets v1.5+ consumers branch on “never-actioned” cleanly (e.g., unwrap_or(0) for optimistic “never-actioned == 0 strikes” semantics, or surface as a domain-specific error otherwise).

PendingActionNotFound(i64)

confirmPendingAction (§F22, #74) targeted a pending_policy_actions.id that doesn’t exist. Handler surfaces this as PendingActionNotFound (404).

PendingAlreadyResolved(i64)

confirmPendingAction / dismissPendingAction (§F22, #74) targeted a row whose resolution is already non-NULL. Handler surfaces this as PendingAlreadyResolved (400). The schema trigger forbids a second NULL → non-NULL transition; the recorder catches it before the UPDATE for a clean lexicon error.

SubjectTakendown(String)

confirmPendingAction (§F22, #74) was called for a subject that already carries an unrevoked Takedown — the action would be redundant and conceptually undefined under the terminal-action posture. v1.6’s auto-dismissal-on-takedown (#76) should resolve all pendings on a takedown, so this state is unreachable in steady state; the variant exists to close the race between a takedown landing and an in-flight confirm.

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<CborError> for Error

fn from(source: CborError) -> Self

Converts to this type from the input type.

impl From<CryptoError> for Error

fn from(source: CryptoError) -> Self

Converts to this type from the input type.

impl From<Error> for Error

fn from(source: Error) -> Self

Converts to this type from the input type.

impl From<Error> for Error

fn from(source: Error) -> Self

Converts to this type from the input type.

impl From<Error> for Error

fn from(e: Error) -> Self

Converts to this type from the input type.

impl From<MigrateError> for Error

fn from(source: MigrateError) -> Self

Converts to this type from the input type.