Struct InMemoryStorage 

pub struct InMemoryStorage { /* private fields */ }

In-memory implementation of the Storage trait using a BTreeMap.

This implementation stores all data in memory and is useful for testing or scenarios where durability is not required. Supports TTL-based expiration via a configurable Clock.

Implementations

impl InMemoryStorage

pub fn new() -> Self

Creates a new InMemoryStorage instance with an empty store.

pub fn with_merge_operator( merge_operator: Arc<dyn MergeOperator + Send + Sync>, ) -> Self

Creates a new InMemoryStorage instance with an optional merge operator.

If a merge operator is provided, the merge method will use it to combine existing values with new values. If no merge operator is provided, the merge method will return an error.

pub fn with_clock(self, clock: Arc<dyn Clock>) -> Self

Sets a custom clock for TTL expiration checks.

pub fn with_default_ttl(self, ttl: u64) -> Self

Sets the default TTL (in milliseconds) for records written with Ttl::Default.

pub fn with_deferred_durability(self) -> Self

Enables deferred durability mode.

When enabled, writes are not marked as durable until flush() or flush_to() is called. This is useful for testing read_durable behavior without depending on SlateDB internals.

pub fn flush_to(&self, seq: u64)

Advances the durable watermark to a specific sequence number.

Panics

Panics if seq is greater than the current written sequence number or less than the current durable sequence number.

Trait Implementations

impl Default for InMemoryStorage

fn default() -> Self

Returns the “default value” for a type.

impl Storage for InMemoryStorage

fn put_with_options<'life0, 'async_trait>( &'life0 self, records: Vec<PutRecordOp>, _options: WriteOptions, ) -> Pin<Box<dyn Future<Output = StorageResult<WriteResult>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Writes a batch of records to the in-memory store.

All records are written atomically within a single write lock acquisition. For in-memory storage, write options are ignored since there is no durable storage to await.

fn merge_with_options<'life0, 'async_trait>( &'life0 self, records: Vec<MergeRecordOp>, _options: WriteOptions, ) -> Pin<Box<dyn Future<Output = StorageResult<WriteResult>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Merges values for the given keys using the configured merge operator.

This method requires a merge operator to be configured during construction. For each record, it will:

1. Get the existing value (if any), excluding expired entries
2. Call the merge operator to combine existing and new values
3. Put the merged result back with the new TTL

If no merge operator is configured, this method will return a StorageError::Storage error.

fn snapshot<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = StorageResult<Arc<dyn StorageSnapshot>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Creates a point-in-time snapshot of the in-memory storage.

The snapshot provides a consistent read-only view of the database at the time the snapshot was created. Reads from the snapshot will not see any subsequent writes to the underlying storage. Expired entries are filtered at read time.

fn apply_with_options<'life0, 'async_trait>( &'life0 self, records: Vec<RecordOp>, _options: WriteOptions, ) -> Pin<Box<dyn Future<Output = StorageResult<WriteResult>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Applies a batch of mixed operations with custom write options.

fn subscribe_durable(&self) -> Receiver<u64>

Subscribes to the durable sequence watermark.

fn flush<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = StorageResult<()>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Flushes all pending writes to durable storage.

fn close<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = StorageResult<()>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Closes the storage, releasing any resources.

fn apply<'life0, 'async_trait>( &'life0 self, ops: Vec<RecordOp>, ) -> Pin<Box<dyn Future<Output = StorageResult<WriteResult>> + Send + 'async_trait>>

where Self: Sync + 'async_trait, 'life0: 'async_trait,

Applies a batch of mixed operations (puts, merges, and deletes) atomically.

fn put<'life0, 'async_trait>( &'life0 self, records: Vec<PutRecordOp>, ) -> Pin<Box<dyn Future<Output = StorageResult<WriteResult>> + Send + 'async_trait>>

where Self: Sync + 'async_trait, 'life0: 'async_trait,

Writes records to storage.

fn merge<'life0, 'async_trait>( &'life0 self, records: Vec<MergeRecordOp>, ) -> Pin<Box<dyn Future<Output = StorageResult<WriteResult>> + Send + 'async_trait>>

where Self: Sync + 'async_trait, 'life0: 'async_trait,

Merges values for the given keys using the configured merge operator.

impl StorageRead for InMemoryStorage

fn get<'life0, 'async_trait>( &'life0 self, key: Bytes, ) -> Pin<Box<dyn Future<Output = StorageResult<Option<Record>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Retrieves a single record by key from the in-memory store.

Returns None if the key does not exist or has expired.

fn scan_iter<'life0, 'async_trait>( &'life0 self, range: BytesRange, ) -> Pin<Box<dyn Future<Output = StorageResult<Box<dyn StorageIterator + Send + 'static>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Returns an iterator over records in the given range.

fn scan<'life0, 'async_trait>( &'life0 self, range: BytesRange, ) -> Pin<Box<dyn Future<Output = StorageResult<Vec<Record>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait,

Collects all records in the range into a Vec.