Struct MigrationTable 

pub struct MigrationTable { /* private fields */ }

Per-scope migration tracker. Insert order doesn’t matter; lookups are O(prefix-set-size), expected ≤ tens of entries even in the largest cluster.

Implementations

impl MigrationTable

pub fn new() -> Self

Empty table — the v1.21 default (no migrations in flight).

pub fn start( &self, prefix: Vec<u8>, from: String, to: String, ) -> Result<(), MigrationError>

Start a migration for prefix. Returns Err if the prefix is already in either map. The caller (server cement) is expected to hold a higher-level lock per MOVE-SCOPE invocation so concurrent operator commands don’t race.

pub fn commit(&self, prefix: &[u8]) -> Option<MigrationState>

Commit an in-flight migration: move the entry from MIGRATING to MIGRATED. Returns the state that was committed, or None when there’s no in-flight migration for prefix (idempotent).

pub fn abort(&self, prefix: &[u8]) -> Option<MigrationState>

Abort an in-flight migration without committing. Drops the entry from MIGRATING; the MIGRATED map is untouched (an aborted migration never moved data). Returns the state that was aborted, or None when there was nothing to abort.

pub fn lookup_migrating(&self, prefix: &[u8]) -> Option<MigrationState>

Look up the in-flight migration for prefix. Returns the state by value (cheap clone — two short Strings) so the caller doesn’t hold the mutex while encoding the -QUIESCED reply.

pub fn lookup_migrated(&self, prefix: &[u8]) -> Option<MigrationState>

Same shape as Self::lookup_migrating, but for committed migrations (post-MOVE-SCOPE-INGEST).

pub fn match_migrating(&self, key: &[u8]) -> Option<MigrationState>

Longest-prefix-match lookup for in-flight migrations. Used by scope_integration::route_write to decide whether to encode -QUIESCED before falling through to the static OwnershipTable::route.

pub fn match_migrated(&self, key: &[u8]) -> Option<MigrationState>

As Self::match_migrating, for the MIGRATED map.

Trait Implementations

impl Debug for MigrationTable

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

Formats the value using the given formatter.

impl Default for MigrationTable

fn default() -> MigrationTable

Returns the “default value” for a type.