Struct MemorySource 

pub struct MemorySource { /* private fields */ }

Replayable in-memory event source backed by one or more batches.

Implementations

impl MemorySource

pub fn empty(schema: Arc<Schema>) -> MemorySource

Creates an empty replayable source with the supplied schema.

Empty derived datasets retain schema and source capabilities while yielding no batches. This is useful for partitioning operations where a valid empty result is distinct from an invalid source definition.

pub fn new(batch: EventBatch) -> MemorySource

Creates a source containing one batch.

pub fn from_batches( batches: Vec<EventBatch>, ) -> Result<MemorySource, LadduDataError>

Validates and creates a source from nonempty schema-compatible batches.

Errors

Returns LadduDataError when batches is empty or contains incompatible schemas.

pub fn from_events<I>( schema: Arc<Schema>, events: I, ) -> Result<MemorySource, LadduDataError>

where I: IntoIterator<Item = OwnedEvent>,

Collects owned events into an in-memory source.

Errors

Returns LadduDataError when an event does not match schema or weighted and unweighted events are mixed.

pub fn schema_arc(&self) -> &Arc<Schema>

Returns the shared schema.

pub fn batches_slice(&self) -> &[EventBatch]

Returns the backing batches.

pub fn into_batches(self) -> Arc<[EventBatch]>

Consumes the source and returns its shared batches.

pub fn into_batch(self) -> Result<EventBatch, LadduDataError>

Consumes and concatenates all batches.

Errors

Returns LadduDataError when no batches are present or their schemas are incompatible.

Trait Implementations

impl Clone for MemorySource

fn clone(&self) -> MemorySource

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MemorySource

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

Formats the value using the given formatter.

impl EventSource for MemorySource

fn schema(&self) -> Result<Arc<Schema>, LadduDataError>

Returns the source schema.

fn capabilities(&self) -> SourceCapabilities

Returns optional source capabilities.

fn num_events(&self) -> Result<Option<u64>, LadduDataError>

Returns the exact event count when cheaply available.

fn weighted_total(&self) -> Result<Option<f64>, LadduDataError>

Returns the exact sum of event weights when cheaply available.

fn batches( &self, plan: ReadPlan, ) -> Result<Box<dyn Iterator<Item = Result<EventBatch, LadduDataError>> + Send>, LadduDataError>

Opens a batch iterator using plan.

impl FragmentedSource for MemorySource

type Key = MemoryFragmentKey

Source-specific fragment key.

fn fragments( &self, ) -> Result<Vec<DataFragment<<MemorySource as FragmentedSource>::Key>>, LadduDataError>

Lists all fragments in global row order.

fn read_fragment_range( &self, key: &<MemorySource as FragmentedSource>::Key, local_start: usize, local_len: usize, chunk_size: Option<usize>, ) -> Result<Box<dyn Iterator<Item = Result<EventBatch, LadduDataError>> + Send>, LadduDataError>

Reads a contiguous range within one fragment.