Struct linera_views::views::set_view::SetView

pub struct SetView<C, I> { /* private fields */ }

A View implementing the set functionality with the index I being any serializable type.

Implementations

impl<C, I> SetView<C, I>

where C: Context, ViewError: From<C::Error>, I: Serialize,

pub fn insert<Q>(&mut self, index: &Q) -> Result<(), ViewError>

where I: Borrow<Q>, Q: Serialize + ?Sized,

Inserts a value. If already present then no effect.

let mut set = SetView::<_, u32>::load(context).await.unwrap();
set.insert(&(34 as u32));
assert_eq!(set.indices().await.unwrap().len(), 1);

pub fn remove<Q>(&mut self, index: &Q) -> Result<(), ViewError>

where I: Borrow<Q>, Q: Serialize + ?Sized,

Removes a value. If absent then nothing is done.

let mut set = SetView::<_, u32>::load(context).await.unwrap();
set.remove(&(34 as u32));
assert_eq!(set.indices().await.unwrap().len(), 0);

pub fn extra(&self) -> &C::Extra

Obtains the extra data.

impl<C, I> SetView<C, I>

where C: Context, ViewError: From<C::Error>, I: Serialize,

pub async fn contains<Q>(&self, index: &Q) -> Result<bool, ViewError>

where I: Borrow<Q>, Q: Serialize + ?Sized,

Returns true if the given index exists in the set.

let mut set: SetView<_, u32> = SetView::load(context).await.unwrap();
set.insert(&(34 as u32));
assert_eq!(set.contains(&(34 as u32)).await.unwrap(), true);
assert_eq!(set.contains(&(45 as u32)).await.unwrap(), false);

impl<C, I> SetView<C, I>

where C: Context, ViewError: From<C::Error>, I: Sync + Clone + Send + Serialize + DeserializeOwned,

pub async fn indices(&self) -> Result<Vec<I>, ViewError>

Returns the list of indices in the set. The order is determined by serialization.

let mut set: SetView<_, u32> = SetView::load(context).await.unwrap();
set.insert(&(34 as u32));
assert_eq!(set.indices().await.unwrap(), vec![34 as u32]);

pub async fn count(&self) -> Result<usize, ViewError>

Returns the number of entries in the set.

let mut set: SetView<_, u32> = SetView::load(context).await.unwrap();
set.insert(&(34 as u32));
assert_eq!(set.count().await.unwrap(), 1);

pub async fn for_each_index_while<F>(&self, f: F) -> Result<(), ViewError>

where F: FnMut(I) -> Result<bool, ViewError> + Send,

Applies a function f on each index. Indices are visited in an order determined by the serialization. If the function returns false, then the loop ends prematurely.

let mut set = SetView::<_, u32>::load(context).await.unwrap();
set.insert(&(34 as u32));
set.insert(&(37 as u32));
set.insert(&(42 as u32));
let mut count = 0;
set.for_each_index_while(|_key| {
    count += 1;
    Ok(count < 2)
})
.await
.unwrap();
assert_eq!(count, 2);

pub async fn for_each_index<F>(&self, f: F) -> Result<(), ViewError>

where F: FnMut(I) -> Result<(), ViewError> + Send,

Applies a function f on each index. Indices are visited in an order determined by the serialization.

let mut set = SetView::<_, u32>::load(context).await.unwrap();
set.insert(&(34 as u32));
set.insert(&(37 as u32));
set.insert(&(42 as u32));
let mut count = 0;
set.for_each_index(|_key| {
    count += 1;
    Ok(())
})
.await
.unwrap();
assert_eq!(count, 3);

Trait Implementations

impl<C, I> ClonableView<C> for SetView<C, I>

where C: Context + Send + Sync, ViewError: From<C::Error>, I: Send + Sync + Serialize,

fn clone_unchecked(&mut self) -> Result<Self, ViewError>

Creates a clone of this view, sharing the underlying storage context but prone to data races which can corrupt the view state.

impl<C: Debug, I: Debug> Debug for SetView<C, I>

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

Formats the value using the given formatter.

impl<C, I> HashableView<C> for SetView<C, I>

where C: Context + Send + Sync, ViewError: From<C::Error>, I: Clone + Send + Sync + Serialize + DeserializeOwned,

type Hasher = CoreWrapper<Sha3_256Core>

How to compute hashes.

fn hash_mut<'life0, 'async_trait>( &'life0 mut self, ) -> Pin<Box<dyn Future<Output = Result<<Self::Hasher as Hasher>::Output, ViewError>> + Send + 'async_trait>>

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

Computes the hash of the values.

fn hash<'life0, 'async_trait>( &'life0 self, ) -> Pin<Box<dyn Future<Output = Result<<Self::Hasher as Hasher>::Output, ViewError>> + Send + 'async_trait>>

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

Computes the hash of the values.

impl<C, I> OutputType for SetView<C, I>

where C: Send + Sync + Context, I: Serialize + DeserializeOwned + Clone + Send + Sync + OutputType,

fn type_name() -> Cow<'static, str>

Type the name.

fn qualified_type_name() -> String

Qualified typename.

fn create_type_info(registry: &mut Registry) -> String

Create type information in the registry and return qualified typename.

async fn resolve( &self, ctx: &ContextSelectionSet<'_>, field: &Positioned<Field>, ) -> ServerResult<Value>

Resolve an output value to async_graphql::Value.

fn introspection_type_name(&self) -> Cow<'static, str>

Introspection type name

impl<C, I> View<C> for SetView<C, I>

where C: Context + Send + Sync, ViewError: From<C::Error>, I: Send + Sync + Serialize,

const NUM_INIT_KEYS: usize = 0usize

The number of keys used for the initialization

fn context(&self) -> &C

Obtains a mutable reference to the internal context.

fn pre_load(context: &C) -> Result<Vec<Vec<u8>>, ViewError>

Creates the keys needed for loading the view

fn post_load(context: C, values: &[Option<Vec<u8>>]) -> Result<Self, ViewError>

Loads a view from the values

fn load<'async_trait>( context: C, ) -> Pin<Box<dyn Future<Output = Result<Self, ViewError>> + Send + 'async_trait>>

where Self: 'async_trait,

Loads a view

fn rollback(&mut self)

Discards all pending changes. After that flush should have no effect to storage.

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

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

Returns true if flushing this view would result in changes to the persistent storage.

fn flush(&mut self, batch: &mut Batch) -> Result<bool, ViewError>

Persists changes to storage. This leaves the view still usable and is essentially neutral to the program running. Crash-resistant storage implementations are expected to accumulate the desired changes in the batch variable first. If the view is dropped without calling flush, staged changes are simply lost. The returned boolean indicates whether the operation removes the view or not.

fn clear(&mut self)

Clears the view. That can be seen as resetting to default. If the clear is followed by a flush then all the relevant data is removed on the storage.

fn new(context: C) -> Result<Self, ViewError>

Builds a trivial view that is already deleted