Nut

Key-value embed database, which is basically port of Bolt DB

Examples

Create db and put something

use nut::DBBuilder;

let mut db = DBBuilder::new("test.db").build().unwrap();
let mut tx = db.begin_rw_tx().unwrap();
{
let mut flowers = tx.create_bucket(b"flowers").unwrap();
// returns mutable reference to bucket,
// which prevents of reborrowing tx

flowers.put(
b"iris",
b"song by American alternative rock band Goo Goo Dolls".to_vec()
).unwrap();
flowers.put(
b"binary data",
vec![127, 127, 127, 127]
).unwrap();

{
// you can create subbuckets as well
let mut annuals = flowers
.create_bucket_if_not_exists(b"annuals").unwrap();

// api is basically same as for transaction
annuals.put(
b"corn",
b"American nu metal band from Bakersfield".to_vec()
).unwrap();
// releasing subbucket
}

// releasing bucket to be able use tx again
}
// due to RAII tx will be automatically closed if no error occured,
// or rolled back if there was some.
// Additionally you can commit or rollback manually
tx.rollback().unwrap();

Getting data back

use nut::DBBuilder;

let mut db = DBBuilder::new("test.db").build().unwrap();

// creating read only transaction
// read only ransaction will be automatically rolled back
let mut tx = db.begin_tx().unwrap();

// getting bucket
let flowers = tx.bucket(b"flowers").unwrap();
let data = flowers.get(b"iris").unwrap();
assert_eq!(
data,
&b"song by American alternative rock band Goo Goo Dolls"[..]
);

Getting available buckets

use nut::DBBuilder;

let mut db = DBBuilder::new("test.db").build().unwrap();
let mut tx = db.begin_tx().unwrap();

{
// .buckets() available to conveniently retrieve all buckets keys
let bucket_names = tx.buckets(); // returns Vec<Vec<u8>>

// bucket key is any binary data, not only string
assert_eq!(bucket_names, vec!["flowers".as_bytes().to_vec()]);
}

{
// additionally there is .cursor() method
// that returns Cursor struct,
// which is able to iterate through bucket contents
let cursor = tx.cursor();

assert_eq!(
&cursor.first().unwrap().value.unwrap(),
&"flowers".as_bytes()
);
}