Crate rusty_leveldb

rusty-leveldb is a reimplementation of LevelDB in pure rust. It depends only on a few crates, and is very close to the original, implementation-wise. The external API is relatively small and should be easy to use.

use rusty_leveldb::{DB, DBIterator, LdbIterator, Options};

let opt = rusty_leveldb::in_memory();
let mut db = DB::open("mydatabase", opt).unwrap();

db.put(b"Hello", b"World").unwrap();
assert_eq!(b"World", db.get(b"Hello").unwrap().as_slice());

let mut iter = db.new_iter().unwrap();
// Note: For efficiency reasons, it's recommended to use advance() and current() instead of
// next() when iterating over many elements.
assert_eq!((b"Hello".to_vec(), b"World".to_vec()), iter.next().unwrap());

db.delete(b"Hello").unwrap();
db.flush().unwrap();

Re-exports

pub use compressor::Compressor;

pub use compressor::CompressorId;

Modules

compressor

env

An env is an abstraction layer that allows the database to run both on different platforms as well as persisting data on disk or in memory.

infolog

Macros

log

Structs

BloomPolicy

A filter policy using a bloom filter internally.

CompressorList

Customize compressor method for leveldb

DB

DB contains the actual database implemenation. As opposed to the original, this implementation is not concurrent (yet).

DBIterator

DBIterator is an iterator over the contents of a database.

DefaultCmp

The default byte-wise comparator.

MemEnv

MemEnv is an in-memory environment that can be used for testing or ephemeral databases. The performance will be better than what a disk environment delivers.

Options

Options contains general parameters for a LevelDB instance. Most of the names are self-explanatory; the defaults are defined in the Default implementation.

PosixDiskEnv

SkipMap

Status

Status encapsulates a StatusCode and an error message. It can be displayed, and also implements Error.

WriteBatch

A WriteBatch contains entries to be written to a MemTable (for example) in a compact form.

Enums

StatusCode

StatusCode describes various failure modes of database operations.

Traits

Cmp

Comparator trait, supporting types that can be nested (i.e., add additional functionality on top of an inner comparator)

FilterPolicy

Encapsulates a filter algorithm allowing to search for keys more efficiently. Usually, policies are used as a BoxedFilterPolicy (see below), so they can be easily cloned and nested.

LdbIterator

An extension of the standard Iterator trait that supports some methods necessary for LevelDB. This works because the iterators used are stateful and keep the last returned element.

Functions

in_memory

Returns Options that will cause a database to exist purely in-memory instead of being stored on disk. This is useful for testing or ephemeral databases.

Type Aliases

Result

LevelDB’s result type