Trait SubstateDatabase 

pub trait SubstateDatabase {
    // Required methods
    fn get_raw_substate_by_db_key(
        &self,
        partition_key: &DbPartitionKey,
        sort_key: &DbSortKey,
    ) -> Option<DbSubstateValue>;
    fn list_raw_values_from_db_key(
        &self,
        partition_key: &DbPartitionKey,
        from_sort_key: Option<&DbSortKey>,
    ) -> Box<dyn Iterator<Item = PartitionEntry> + '_>;
}

A read interface between Track and a database vendor.

Required Methods

fn get_raw_substate_by_db_key( &self, partition_key: &DbPartitionKey, sort_key: &DbSortKey, ) -> Option<DbSubstateValue>

Reads a substate value by its db partition and db sort key, or Option::None if missing.

Alternatives

It’s likely easier to use the get_substate or get_raw_substate methods instead, which allow providing logical keys. These methods should also exist on the database type as long as the SubstateDatabaseExtensions trait is in scope.

fn list_raw_values_from_db_key( &self, partition_key: &DbPartitionKey, from_sort_key: Option<&DbSortKey>, ) -> Box<dyn Iterator<Item = PartitionEntry> + '_>

Iterates over all entries of the given partition (starting either from the beginning, or from the given DbSortKey), in a lexicographical order (ascending) of the DbSortKeys. Note: If the exact given starting key does not exist, the iteration starts with its immediate successor.

Alternatives

There are lots of methods starting list_ which allow iterating using more intuitive abstractions. These methods are present as long as the SubstateDatabaseExtensions trait is in scope.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors