Struct MigrationController 

pub struct MigrationController { /* private fields */ }

Manages the state machine for a single migration.

Example

use lattice_embed::migration::{MigrationController, MigrationPlan};
use lattice_embed::EmbeddingModel;

let plan = MigrationPlan {
    id: "mig-001".to_string(),
    source_model: EmbeddingModel::BgeSmallEnV15,
    target_model: EmbeddingModel::BgeBaseEnV15,
    total_embeddings: 100,
    batch_size: 50,
    created_at: "2026-01-27T00:00:00Z".to_string(),
};

let mut ctrl = MigrationController::new(plan);
ctrl.start().unwrap();
ctrl.record_progress(50).unwrap();

let report = ctrl.progress();
assert!(report.state.is_active());
assert_eq!(report.state.processed(), 50);

Implementations

impl MigrationController

pub fn new(plan: MigrationPlan) -> Self

Create a new migration controller from a plan.

pub fn start(&mut self) -> Result<(), MigrationError>

Start the migration (Planned -> InProgress).

pub fn record_progress( &mut self, newly_processed: usize, ) -> Result<(), MigrationError>

Record that newly_processed embeddings were completed.

pub fn record_error(&mut self)

Record a non-fatal error during processing.

pub fn record_skip(&mut self, reason: SkipReason) -> Result<(), MigrationError>

Record an item that will be permanently skipped.

Example

use lattice_embed::migration::{MigrationController, MigrationPlan, SkipReason};
use lattice_embed::EmbeddingModel;

let plan = MigrationPlan {
    id: "mig-001".to_string(),
    source_model: EmbeddingModel::BgeSmallEnV15,
    target_model: EmbeddingModel::BgeBaseEnV15,
    total_embeddings: 100,
    batch_size: 50,
    created_at: "2026-01-27T00:00:00Z".to_string(),
};

let mut ctrl = MigrationController::new(plan);
ctrl.start().unwrap();
ctrl.record_skip(SkipReason::ContentTooLarge { size: 50000, max: 8192 }).unwrap();
assert_eq!(ctrl.state().skipped(), 1);

pub fn skip_reasons(&self) -> &[SkipReason]

Returns the list of reasons why entries were skipped during migration.

pub fn effective_coverage(&self) -> f64

Returns the effective coverage fraction (0.0–1.0) of the migration.

pub fn pause(&mut self, reason: impl Into<String>) -> Result<(), MigrationError>

Pause the migration (InProgress -> Paused).

pub fn resume(&mut self) -> Result<(), MigrationError>

Resume the migration (Paused/Failed -> InProgress).

pub fn fail(&mut self, error: impl Into<String>) -> Result<(), MigrationError>

Fail the migration (InProgress -> Failed).

pub fn cancel(&mut self) -> Result<(), MigrationError>

Cancel the migration (any non-terminal state -> Cancelled).

pub fn progress(&self) -> MigrationProgress

Get a snapshot of current progress.

pub fn state(&self) -> &MigrationState

Returns the current migration state.

pub fn plan(&self) -> &MigrationPlan

Returns the migration plan.

Trait Implementations

impl Debug for MigrationController

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

Formats the value using the given formatter.