Trait secret_cosmwasm_std::ReadonlyStorage

pub trait ReadonlyStorage {
    fn get(&self, key: &[u8]) -> Option<Vec<u8>>;
    fn range<'a>(
        &'a self, 
        start: Option<&[u8]>, 
        end: Option<&[u8]>, 
        order: Order
    ) -> Box<dyn Iterator<Item = KV> + 'a>;
}

ReadonlyStorage is access to the contracts persistent data store

Required Methods

fn get(&self, key: &[u8]) -> Option<Vec<u8>>

Returns None when key does not exist. Returns Some(Vec) when key exists.

Note: Support for differentiating between a non-existent key and a key with empty value is not great yet and might not be possible in all backends. But we’re trying to get there.

fn range<'a>(
    &'a self,
    start: Option<&[u8]>,
    end: Option<&[u8]>,
    order: Order
) -> Box<dyn Iterator<Item = KV> + 'a>

Allows iteration over a set of key/value pairs, either forwards or backwards.

The bound start is inclusive and end is exclusive.

If start is lexicographically greater than or equal to end, an empty range is described, mo matter of the order.

Implementors

impl ReadonlyStorage for MemoryStorage