Expand description
yrs-lmdb is a persistence layer allowing to store Yrs documents and providing convenient utility functions to work with them, using LMDB for persistent backend.
§Example
use std::sync::Arc;
use lmdb_rs::core::DbCreate;
use lmdb_rs::Environment;
use yrs::{Doc, Text, Transact};
use yrs_kvstore::DocOps;
use yrs_lmdb::LmdbStore;
let env = Arc::new(Environment::new()
.autocreate_dir(true)
.max_dbs(4)
.open("my-lmdb-dir", 0o777)
.unwrap());
let h = Arc::new(env.create_db("yrs", DbCreate).unwrap());
let doc = Doc::new();
let text = doc.get_or_insert_text("text");
// restore document state from DB
{
let db_txn = env.get_reader().unwrap();
let db = LmdbStore::from(db_txn.bind(&h));
db.load_doc("my-doc-name", &mut doc.transact_mut()).unwrap();
}
// another options is to flush document state right away, but
// this requires a read-write transaction
{
let db_txn = env.new_transaction().unwrap();
let db = LmdbStore::from(db_txn.bind(&h));
let doc = db.flush_doc_with("my-doc-name", yrs::Options::default()).unwrap();
db_txn.commit().unwrap(); // flush may modify internal store state
}
// configure document to persist every update and
// occassionaly compact them into document state
let sub = {
let env = env.clone();
let h = h.clone();
let options = doc.options().clone();
doc.observe_update_v1(move |_,e| {
let db_txn = env.new_transaction().unwrap();
let db = LmdbStore::from(db_txn.bind(&h));
let seq_nr = db.push_update("my-doc-name", &e.update).unwrap();
if seq_nr % 64 == 0 {
// occassinally merge updates into the document state
db.flush_doc_with("my-doc-name", options.clone()).unwrap();
}
db_txn.commit().unwrap();
})
};
text.insert(&mut doc.transact_mut(), 0, "a");
text.insert(&mut doc.transact_mut(), 1, "b");
text.insert(&mut doc.transact_mut(), 2, "c");
Re-exports§
pub use yrs_kvstore as store;