Struct MemorySaver 

pub struct MemorySaver { /* private fields */ }

In-memory checkpoint storage.

Stores checkpoints in a HashMap in memory. Fast and simple, but does not persist across process restarts.

Example

use rust_langgraph::checkpoint_backends::memory::MemorySaver;
use rust_langgraph::checkpoint::BaseCheckpointSaver;
use rust_langgraph::Config;

#[tokio::main]
async fn main() {
    let saver = MemorySaver::new();
    let config = Config::new().with_thread_id("test-123");
     
    // Use saver with graph...
}

Implementations

impl MemorySaver

pub fn new() -> Self

Create a new in-memory checkpoint saver

pub async fn len(&self) -> usize

Get the number of checkpoints stored

pub async fn is_empty(&self) -> bool

Check if storage is empty

pub async fn clear(&self)

Clear all stored checkpoints

Trait Implementations

impl BaseCheckpointSaver for MemorySaver

fn get_tuple<'life0, 'life1, 'async_trait>( &'life0 self, config: &'life1 Config, ) -> Pin<Box<dyn Future<Output = Result<Option<CheckpointTuple>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Get a checkpoint tuple for the given configuration.

fn put<'life0, 'life1, 'life2, 'life3, 'async_trait>( &'life0 self, checkpoint: &'life1 Checkpoint, metadata: &'life2 CheckpointMetadata, config: &'life3 Config, ) -> Pin<Box<dyn Future<Output = Result<Config>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait, 'life2: 'async_trait, 'life3: 'async_trait,

Save a checkpoint.

fn list<'life0, 'life1, 'async_trait>( &'life0 self, config: &'life1 Config, limit: Option<usize>, ) -> Pin<Box<dyn Future<Output = Result<Vec<CheckpointTuple>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

List checkpoints for a given configuration.

fn get<'life0, 'life1, 'async_trait>( &'life0 self, checkpoint_id: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<Option<Checkpoint>>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Get a specific checkpoint by ID

fn delete_thread<'life0, 'life1, 'async_trait>( &'life0 self, thread_id: &'life1 str, ) -> Pin<Box<dyn Future<Output = Result<()>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Delete all checkpoints for a thread

fn prune<'life0, 'life1, 'async_trait>( &'life0 self, thread_id: &'life1 str, keep: usize, ) -> Pin<Box<dyn Future<Output = Result<usize>> + Send + 'async_trait>>

where Self: 'async_trait, 'life0: 'async_trait, 'life1: 'async_trait,

Prune old checkpoints, keeping only the most recent ones

impl Clone for MemorySaver

fn clone(&self) -> MemorySaver

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MemorySaver

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

Formats the value using the given formatter.

impl Default for MemorySaver

fn default() -> Self

Returns the “default value” for a type.