Struct common::cache_storage::cache_double_map::CacheStorageDoubleMap

pub struct CacheStorageDoubleMap<Key1, Key2, Value, Storage>where
    Key1: Ord + FullCodec + Clone,
    Key2: Ord + FullCodec + Clone,
    Value: FullCodec + Clone + PartialEq,
    Storage: IterableStorageDoubleMap<Key1, Key2, Value>,{ /* private fields */ }

CacheStorageDoubleMap is a wrapper of StorageDoubleMap that follows the idea one read, one write the same data.

Implementations

impl<Key1, Key2, Value, Storage> CacheStorageDoubleMap<Key1, Key2, Value, Storage>where Key1: Ord + FullCodec + Clone, Key2: Ord + FullCodec + Clone, Value: FullCodec + Clone + PartialEq, Storage: IterableStorageDoubleMap<Key1, Key2, Value>,

pub fn new() -> Self

pub fn contains_key(&self, key1: &Key1, key2: &Key2) -> bool

pub fn get(&mut self, key1: &Key1, key2: &Key2) -> Option<&Value>

Returns the cached value if it is, otherwise tries to get the value from Storage. If Storage has the value, CacheStorageDoubleMap caches it and returns. If Storage has no the value, the None is kept and returned.

When client calls get with the same keys again, the cached value or None is returned without trying to get it from Storage.

pub fn get_by_prefix(&mut self, key1: &Key1) -> BTreeMap<Key2, Value>

Loads and returns all values by key1. Values of Removed items are omitted.

pub fn set(&mut self, key1: &Key1, key2: &Key2, value: Value)

Sets the value and mark it as Updated

pub fn remove(&mut self, key1: &Key1, key2: &Key2)

Marks the cached value as Removed. Now the None will be returned for get with the same keys If there is no this cached value, then None is kept or Removed if Storage contains it.

pub fn commit(&mut self)

Syncs all the data with Storage. Inserts in Storage all values are marked as Updated and marks them as Original. Removes from Storage all values are marked as Removed. Does nothing with Original values. And then removes all non-Original values.

pub fn reset(&mut self)