Trait StateReader 

pub trait StateReader: Send + Sync {
    // Required methods
    fn contains(&self, address: &str) -> Result<bool, StateDatabaseError>;
    fn get(&self, address: &str) -> Result<Option<Vec<u8>>, StateDatabaseError>;
    fn leaves(
        &self,
        prefix: Option<&str>,
    ) -> Result<Box<StateIter>, StateDatabaseError>;
}

Required Methods

fn contains(&self, address: &str) -> Result<bool, StateDatabaseError>

Returns true if the given address exists in State; false, otherwise.

Will return a StateDatabaseError if any errors occur while querying for the existence of the given address.

fn get(&self, address: &str) -> Result<Option<Vec<u8>>, StateDatabaseError>

Returns the data for a given address, if it exists. In the case where the address exists, but has no data, it will return None.

Will return an StateDatabaseError::NotFound, if the given address is not in State.

fn leaves( &self, prefix: Option<&str>, ) -> Result<Box<StateIter>, StateDatabaseError>

A state value is considered a leaf if it has data stored at the address.

Returns an iterator over address-value pairs in state.

Returns Err if the prefix is invalid, or if any other database errors occur while creating the iterator.

Trait Implementations

impl From<Box<dyn StateReader>> for IdentityView

fn from(state_reader: Box<dyn StateReader>) -> Self

Converts to this type from the input type.

impl From<Box<dyn StateReader>> for SettingsView

fn from(state_reader: Box<dyn StateReader>) -> Self

Converts to this type from the input type.

Dyn Compatibility

This trait is dyn compatible.

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

Implementors

impl StateReader for DecodedMerkleStateReader