Class MemoryStateStore

In-process StateStore backed by a Map, with lazy TTL expiration.

Remarks

Suitable for single-process deployments and tests. Expired entries are evicted lazily on access (get, has, keys) rather than by a background timer, using the injected Clock to determine the current time. State is not shared across processes. Optionally, a background sweeper (see the constructor's sweepIntervalMs) can proactively purge expired keys so memory is reclaimed even for keys that are never read again.

Example

const store = new MemoryStateStore()
await store.set('room:1', { peers: 2 }, 60_000) // expires in 60s
await store.get<{ peers: number }>('room:1')     // { peers: 2 }

Implements

StateStore

Index

Constructors

constructor

Methods

delete get has keys set stop

Constructors

constructor

new MemoryStateStore(_clock?: Clock, sweepIntervalMs?: number): MemoryStateStore
Parameters
- _clock: Clock = systemClock
  Clock used to evaluate TTL expiration.
- OptionalsweepIntervalMs: number
  When set (> 0), a background timer proactively purges expired entries every this-many milliseconds, reclaiming memory for keys that are never accessed again. Omit to disable (the default): expiry then stays purely lazy via get/has/keys. The timer is unref'd where supported so it never keeps a Node process alive.
Returns MemoryStateStore
Default Value
systemClock
- Defined in packages/core/src/StateStore.ts:82

Methods

delete

delete(key: string): Promise<void>
Removes the entry at key, if any.
Parameters
- key: string
  The key to delete.
Returns Promise<void>
Implementation of StateStore.delete
- Defined in packages/core/src/StateStore.ts:134

get

get<T>(key: string): Promise<T | undefined>
Reads the value stored at key.
Type Parameters
- T
  Expected type of the stored value.
Parameters
- key: string
  The key to read.
Returns Promise<T | undefined>
The stored value, or undefined if the key is absent or expired.
Implementation of StateStore.get
- Defined in packages/core/src/StateStore.ts:121

has

has(key: string): Promise<boolean>
Reports whether a live (non-expired) entry exists at key.
Parameters
- key: string
  The key to test.
Returns Promise<boolean>
true if a non-expired value is present.
Implementation of StateStore.has
- Defined in packages/core/src/StateStore.ts:139

keys

keys(prefix?: string): Promise<string[]>
Lists the keys of all live entries, optionally filtered by prefix.
Parameters
- Optionalprefix: string
  When provided, only keys starting with this string are returned.
Returns Promise<string[]>
The matching keys.
Implementation of StateStore.keys
- Defined in packages/core/src/StateStore.ts:144

set

set<T>(key: string, value: T, ttlMs?: number): Promise<void>
Writes a value at key, optionally with a TTL after which it expires.
Type Parameters
- T
  Type of the value being stored.
Parameters
- key: string
  The key to write.
- value: T
  The value to store.
- OptionalttlMs: number
  Optional lifetime in milliseconds; if omitted the entry never expires.
Returns Promise<void>
Implementation of StateStore.set
- Defined in packages/core/src/StateStore.ts:126

stop

stop(): void
Stops the background TTL sweeper (if one was started). Idempotent.

Returns void
- Defined in packages/core/src/StateStore.ts:95

Class MemoryStateStore

Remarks

Example

Implements

Index

Constructors

Methods

Constructors

constructor

Parameters

Returns MemoryStateStore

Default Value

Methods

delete

Parameters

Returns Promise<void>

get

Type Parameters

Parameters

Returns Promise<T | undefined>

has

Parameters

Returns Promise<boolean>

keys

Parameters

Returns Promise<string[]>

set

Type Parameters

Parameters

Returns Promise<void>

stop

Returns void

Settings

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