Struct CustomCollectionView

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

A map view that serializes the indices.

Implementations

impl<I: CustomSerialize, W: View> CustomCollectionView<W::Context, I, W>

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

where I: Borrow<Q>, Q: CustomSerialize,

Loads a subview for the data at the given index in the collection. If an entry is absent then a default entry is added to the collection. The resulting view can be modified.

let mut view: CustomCollectionView<_, u128, RegisterView<_, String>> =
    CustomCollectionView::load(context).await.unwrap();
let subview = view.load_entry_mut(&23).await.unwrap();
let value = subview.get();
assert_eq!(*value, String::default());

pub async fn try_load_entry<Q>( &self, index: &Q, ) -> Result<Option<ReadGuardedView<'_, W>>, ViewError>

where I: Borrow<Q>, Q: CustomSerialize,

Loads a subview for the data at the given index in the collection. If an entry is absent then None is returned. The resulting view cannot be modified. May fail if one subview is already being visited.

let mut view: CustomCollectionView<_, u128, RegisterView<_, String>> =
    CustomCollectionView::load(context).await.unwrap();
{
    let _subview = view.load_entry_mut(&23).await.unwrap();
}
{
    let subview = view.try_load_entry(&23).await.unwrap().unwrap();
    let value = subview.get();
    assert_eq!(*value, String::default());
}
assert!(view.try_load_entry(&24).await.unwrap().is_none());

pub async fn try_load_entries<'a, Q>( &self, indices: impl IntoIterator<Item = &'a Q>, ) -> Result<Vec<Option<ReadGuardedView<'_, W>>>, ViewError>

where I: Borrow<Q>, Q: CustomSerialize + 'a,

Load multiple entries for reading at once. The entries in indices have to be all distinct.

let mut view: CustomCollectionView<_, u128, RegisterView<_, String>> =
    CustomCollectionView::load(context).await.unwrap();
{
    let _subview = view.load_entry_mut(&23).await.unwrap();
}
let subviews = view.try_load_entries(&[23, 42]).await.unwrap();
let value0 = subviews[0].as_ref().unwrap().get();
assert_eq!(*value0, String::default());

pub async fn try_load_entries_pairs<Q>( &self, indices: impl IntoIterator<Item = Q>, ) -> Result<Vec<(Q, Option<ReadGuardedView<'_, W>>)>, ViewError>

where I: Borrow<Q>, Q: CustomSerialize + Clone,

Loads multiple entries for reading at once with their keys. The entries in indices have to be all distinct.

let mut view: CustomCollectionView<_, u128, RegisterView<_, String>> =
    CustomCollectionView::load(context).await.unwrap();
{
    let _subview = view.load_entry_mut(&23).await.unwrap();
}
let indices = [23, 42];
let subviews = view.try_load_entries_pairs(indices).await.unwrap();
let value0 = subviews[0].1.as_ref().unwrap().get();
assert_eq!(*value0, String::default());

pub async fn try_load_all_entries( &self, ) -> Result<Vec<(I, ReadGuardedView<'_, W>)>, ViewError>

where I: CustomSerialize,

Load all entries for reading at once.

let mut view: CustomCollectionView<_, u128, RegisterView<_, String>> =
    CustomCollectionView::load(context).await.unwrap();
{
    let _subview = view.load_entry_mut(&23).await.unwrap();
}
let subviews = view.try_load_all_entries().await.unwrap();
assert_eq!(subviews.len(), 1);

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

where I: Borrow<Q>, Q: CustomSerialize,

Marks the entry so that it is removed in the next flush.

let mut view: CustomCollectionView<_, u128, RegisterView<_, String>> =
    CustomCollectionView::load(context).await.unwrap();
let subview = view.load_entry_mut(&23).await.unwrap();
let value = subview.get_mut();
*value = String::from("Hello");
view.reset_entry_to_default(&23).unwrap();
let subview = view.load_entry_mut(&23).await.unwrap();
let value = subview.get_mut();
assert_eq!(*value, String::default());

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

where I: Borrow<Q>, Q: CustomSerialize,

Removes an entry from the CollectionView. If absent nothing happens.

let mut view: CustomCollectionView<_, u128, RegisterView<_, String>> =
    CustomCollectionView::load(context).await.unwrap();
let subview = view.load_entry_mut(&23).await.unwrap();
let value = subview.get_mut();
assert_eq!(*value, String::default());
view.remove_entry(&23);
let keys = view.indices().await.unwrap();
assert_eq!(keys.len(), 0);

pub fn extra(&self) -> &<W::Context as Context>::Extra

Gets the extra data.

impl<I: CustomSerialize + Send, W: View> CustomCollectionView<W::Context, I, W>

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

Returns the list of indices in the collection in the order determined by the custom serialization.

let mut view: CustomCollectionView<_, u128, RegisterView<_, String>> =
    CustomCollectionView::load(context).await.unwrap();
view.load_entry_mut(&23).await.unwrap();
view.load_entry_mut(&25).await.unwrap();
let indices = view.indices().await.unwrap();
assert_eq!(indices, vec![23, 25]);

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

Returns the number of entries in the collection.

let mut view: CollectionView<_, u64, RegisterView<_, String>> =
    CollectionView::load(context).await.unwrap();
view.load_entry_mut(&23).await.unwrap();
view.load_entry_mut(&25).await.unwrap();
assert_eq!(view.count().await.unwrap(), 2);

impl<I: CustomSerialize, W: View> CustomCollectionView<W::Context, I, W>

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 custom serialization. If the function f returns false, then the loop ends prematurely.

let mut view: CustomCollectionView<_, u128, RegisterView<_, String>> =
    CustomCollectionView::load(context).await.unwrap();
view.load_entry_mut(&28).await.unwrap();
view.load_entry_mut(&24).await.unwrap();
view.load_entry_mut(&23).await.unwrap();
let mut part_indices = Vec::new();
view.for_each_index_while(|index| {
    part_indices.push(index);
    Ok(part_indices.len() < 2)
})
.await
.unwrap();
assert_eq!(part_indices, vec![23, 24]);

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

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

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

let mut view: CustomCollectionView<_, u128, RegisterView<_, String>> =
    CustomCollectionView::load(context).await.unwrap();
view.load_entry_mut(&28).await.unwrap();
view.load_entry_mut(&24).await.unwrap();
view.load_entry_mut(&23).await.unwrap();
let mut indices = Vec::new();
view.for_each_index(|index| {
    indices.push(index);
    Ok(())
})
.await
.unwrap();
assert_eq!(indices, vec![23, 24, 28]);

Trait Implementations

impl<I: Send + Sync, W: ClonableView> ClonableView for CustomCollectionView<W::Context, I, W>

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<K, V> ContainerType for CustomCollectionView<V::Context, K, V>

where K: InputType + OutputType + CustomSerialize + Debug, V: View + OutputType,

async fn resolve_field(&self, ctx: &Context<'_>) -> ServerResult<Option<Value>>

Resolves a field value and outputs it as a json value async_graphql::Value.

async fn find_entity( &self, ctx: &Context<'_>, params: &Value, ) -> ServerResult<Option<Value>>

Find the GraphQL entity with the given name from the parameter.

fn collect_all_fields<'a>( &'a self, ctx: &ContextBase<'a, &'a Positioned<SelectionSet>>, fields: &mut Fields<'a>, ) -> Result<(), ServerError>

where Self: Send + Sync,

Collect all the fields of the container that are queried in the selection set.

impl<C: Debug, I: Debug, W: Debug> Debug for CustomCollectionView<C, I, W>

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

Formats the value using the given formatter.

impl<I, W: HashableView> HashableView for CustomCollectionView<W::Context, I, W>

where Self: View,

type Hasher = CoreWrapper<Sha3_256Core>

How to compute hashes.

async fn hash_mut( &mut self, ) -> Result<<Self::Hasher as Hasher>::Output, ViewError>

Same as hash but guaranteed to be wait-free.

async fn hash(&self) -> Result<<Self::Hasher as Hasher>::Output, ViewError>

Computes the hash of the values.

impl<K, V> OutputType for CustomCollectionView<V::Context, K, V>

where K: InputType + OutputType + CustomSerialize + Debug, V: View + OutputType,

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

Type the name.

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 qualified_type_name() -> String

Qualified typename.

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

Introspection type name

impl<C: Send + Sync, K: InputType, V: OutputType> TypeName for CustomCollectionView<C, K, V>

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

Returns a GraphQL type name.

impl<I: Send + Sync, W: View> View for CustomCollectionView<W::Context, I, W>

const NUM_INIT_KEYS: usize = 0usize

The number of keys used for the initialization

type Context = <W as View>::Context

The type of context stored in this view

fn context(&self) -> &Self::Context

Obtains a mutable reference to the internal context.

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

Creates the keys needed for loading the view

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

Loads a view from the values

fn rollback(&mut self)

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

async fn has_pending_changes(&self) -> bool

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 load( context: Self::Context, ) -> impl Future<Output = Result<Self, ViewError>> + Send + Sync

Loads a view

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

Builds a trivial view that is already deleted

impl<K, V> ObjectType for CustomCollectionView<V::Context, K, V>

where K: InputType + OutputType + CustomSerialize + Debug, V: View + OutputType,