pub trait Storage {
    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 = Record> + 'a>; fn set(&mut self, key: &[u8], value: &[u8]); fn remove(&mut self, key: &[u8]); }
Expand description

Storage provides read and write access to a persistent storage. If you only want to provide read access, provide &Storage

Required Methods

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.

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.

Removes a database entry at key.

The current interface does not allow to differentiate between a key that existed before and one that didn’t exist. See