Struct SnapshotWithUpdates

pub struct SnapshotWithUpdates<Snapshot, Updates> {
    pub snapshot: Snapshot,
    pub updates: Updates,
}

Wraps a ‘snapshot’ (initial data) with updates (some kind of update which can be applied to the snapshot to update).

This is useful for modelling behaviour of CRUD repositories where updates are also monitored.

Fields

snapshot: Snapshot

Initial snapshot of the data

updates: Updates

Stream of updates that can be applied to the snapshot

Implementations

impl<Key, Value, Snapshot, Updates> SnapshotWithUpdates<Snapshot, Updates>

where Key: Clone + Hash + Eq, Value: Clone, Snapshot: IntoIterator<Item = (Key, Value)>, Updates: Stream, Updates::Item: IntoIterator<Item = (Key, Option<Value>)>,

pub fn join_with_optional_parent<ParentKey, ParentValue, ParentSnapshot, ParentUpdates>( self, other: SnapshotWithUpdates<ParentSnapshot, ParentUpdates>, f: impl FnMut(&Key) -> ParentKey, ) -> SnapshotWithUpdates<impl IntoIterator<Item = ((ParentKey, Key), (Option<ParentValue>, Value))>, impl Stream<Item = impl IntoIterator<Item = ((ParentKey, Key), Option<(Option<ParentValue>, Value)>)>>>

where ParentKey: Clone + Hash + Eq, Snapshot::Item: Clone, ParentSnapshot: IntoIterator<Item = (ParentKey, ParentValue)>, ParentValue: Clone, ParentUpdates: Stream, ParentUpdates::Item: IntoIterator<Item = (ParentKey, Option<ParentValue>)>,

pub fn join_with_parent<ParentKey, ParentValue, ParentSnapshot, ParentUpdates>( self, other: SnapshotWithUpdates<ParentSnapshot, ParentUpdates>, f: impl FnMut(&Key) -> ParentKey, ) -> SnapshotWithUpdates<impl IntoIterator<Item = ((ParentKey, Key), (ParentValue, Value))>, impl Stream<Item = impl IntoIterator<Item = ((ParentKey, Key), Option<(ParentValue, Value)>)>>>

where ParentKey: Clone + Hash + Eq, Snapshot::Item: Clone, ParentSnapshot: IntoIterator<Item = (ParentKey, ParentValue)>, ParentValue: Clone, ParentUpdates: Stream, ParentUpdates::Item: IntoIterator<Item = (ParentKey, Option<ParentValue>)>,

impl<Snapshot, Updates> SnapshotWithUpdates<Snapshot, Updates>

pub fn new(snapshot: Snapshot, updates: Updates) -> Self

Constructor

pub fn into_inner(self) -> (Snapshot, Updates)

Converts the struct into a tuple of (snapshot, updates)

pub async fn from_stream(stream: Updates) -> Option<Self>

where Updates: Stream<Item = Snapshot> + Unpin,

Creates SnapshotWithUpdates by taking the first item of the stream as the ‘snapshot’ and subsequent items as ‘updates’. Returns None if the stream doesn’t contain any items.

pub fn into_stream( self, ) -> impl Stream<Item = SnapshotOrUpdate<Snapshot, Updates::Item>>

where Updates: Stream,

Converts SnapshotWithUpdates into a Stream of SnapshotOrUpdate

pub fn flatten(self) -> impl Stream<Item = Snapshot>

where Updates: Stream<Item = Snapshot>,

Converts SnapshotWithUpdates into a Stream snapshots when Updates::Item is Snapshot

impl<Key, Value, Snapshot, Updates> SnapshotWithUpdates<Snapshot, Updates>

where Key: Clone + Hash + Eq, Value: Clone, Snapshot: IntoIterator<Item = (Key, Value)>, Updates: Stream, Updates::Item: IntoIterator<Item = (Key, Option<Value>)>,

pub fn into_snapshots( self, ) -> SnapshotWithUpdates<HashMap<Key, Value>, impl Stream<Item = HashMap<Key, Value>>>

Aggregates updates into a stream of snapshots by sequentially applying updates to the initial snapshot.

pub fn map_keys<R>( self, f: impl Fn(Key) -> R + Clone, ) -> SnapshotWithUpdates<impl IntoIterator<Item = (R, Value)>, impl Stream<Item = impl IntoIterator<Item = (R, Option<Value>)>>>

pub fn map_values<R>( self, f: impl Fn(Value) -> R + Clone, ) -> SnapshotWithUpdates<impl IntoIterator<Item = (Key, R)>, impl Stream<Item = impl IntoIterator<Item = (Key, Option<R>)>>>

pub fn filter( self, f: impl Fn(&Key, &Value) -> bool + Clone, ) -> SnapshotWithUpdates<impl IntoIterator<Item = (Key, Value)>, impl Stream<Item = impl IntoIterator<Item = (Key, Option<Value>)>>>

pub fn filter_keys( self, f: impl Fn(&Key) -> bool + Clone, ) -> SnapshotWithUpdates<impl IntoIterator<Item = (Key, Value)>, impl Stream<Item = impl IntoIterator<Item = (Key, Option<Value>)>>>

Trait Implementations

impl<Snapshot: Debug, Updates: Debug> Debug for SnapshotWithUpdates<Snapshot, Updates>

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

Formats the value using the given formatter.

impl<T: Clone + Send + Sync + 'static> From<Receiver<T>> for SnapshotWithUpdates<T, Skip<WatchStream<T>>>

Available on crate feature tokio-sync only.

fn from(rx: Receiver<T>) -> Self

Converts to this type from the input type.