kandra-core/io.kandra.core/KandraConsistency

KandraConsistency

enum KandraConsistency : Enum<KandraConsistency>

Consistency levels for ScyllaDB/Cassandra operations.

Write consistency

Default: LOCAL_QUORUM — majority of replicas in the local DC must acknowledge.

Read consistency

Default: LOCAL_ONE — single replica in the local DC, fastest possible read.

LWT serial consistency (for `saveIfNotExists` and a `@Version`-locked `update`)

Use LOCAL_SERIAL (default) for Paxos within the local DC only. Use SERIAL for globally unique constraints (e.g. a username unique across ALL DCs) or when an optimistic-locked update must not let a concurrent write land undetected on a different DC during a network partition (GH #134) — LOCAL_SERIAL only guarantees the check is linearizable within the DC the write went through.

Consistency resolution order (highest priority first)

Per-operation parameter on the repository method
@ReadConsistency / @WriteConsistency annotation on the entity class
KandraConfig.consistency.defaultRead / defaultWrite

Entries

Single replica in the local DC — fastest read, weakest guarantee.

LOCAL_QUORUM

Majority of replicas in the local DC — default write.

EACH_QUORUM

Write to majority in EVERY DC — strongest multi-DC write guarantee.

LOCAL_SERIAL

Paxos serial consistency in local DC only — default for LWT.

SERIAL

Global Paxos across all DCs — required for globally unique constraints.

Properties

entries

val entries: EnumEntries<KandraConsistency>

Returns a representation of an immutable list of all enum entries, in the order they're declared.

isSerial

val isSerial: Boolean

isValidForRead

val isValidForRead: Boolean

Whether this level is valid as the regular (non-serial) consistency of a read operation.

isValidForWrite

val isValidForWrite: Boolean

Whether this level is valid as the regular (non-serial) consistency of a write operation.

name

val name: String

ordinal

val ordinal: Int

Functions

valueOf

fun valueOf(value: String): KandraConsistency

Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

values

fun values(): Array<KandraConsistency>

Returns an array containing the constants of this enum type, in the order they're declared.