LevelDb.Managed 1.0.0

LevelDb.Managed

A pure managed .NET library for reading and writing LevelDB databases - no native binaries, no P/Invoke - with a Chromium layer on top for the stores Chromium-based apps (Chrome, Electron, CEF) keep on disk.

Two packages:

• LevelDb.Managed - the LevelDB format itself: reading live databases lock-free (log, sstables, MANIFEST, correct newest-wins merge semantics), append-only writing via WriteBatch, and a raw record layer that surfaces superseded and deleted records for forensic use.
• LevelDb.Managed.Chromium - Chromium's Local Storage on top of it: per-storage-key string key/value access, handling Chromium's key layout and value encodings.

Installation

dotnet add package LevelDb.Managed
dotnet add package LevelDb.Managed.Chromium

LevelDb.Managed.Chromium depends on LevelDb.Managed, so for Local Storage work the second command is all you need.

Usage

Reading a LevelDB database

using LevelDbManaged;

using ReadOnlyLevelDb db = LevelDb.OpenReadOnly(@"path\to\leveldb");

byte[]? value = db.Get("some-key"u8);

foreach ((byte[] key, byte[] val) in db.Enumerate())
{
    // newest-wins view of the current database state
}

Writing

using LevelDbManaged;

using LevelDb db = LevelDb.Open(@"path\to\leveldb");

WriteBatch batch = new();
batch.Put("key"u8, "value"u8);
batch.Delete("old-key"u8);
db.Write(batch);

Chromium Local Storage

using LevelDbManaged.Chromium;

using ReadOnlyLocalStorageStore store =
    LocalStorageStore.OpenReadOnly(@"...\User Data\Default\Local Storage\leveldb");

foreach (string storageKey in store.EnumerateStorageKeys())
{
    IReadOnlyDictionary<string, string> items = store.GetItems(storageKey);
}

Writing works the same way through LocalStorageStore.Open and PutItems.

Raw records (forensics)

using LevelDbManaged;

LevelDbRecordReader reader = new(@"path\to\leveldb");

foreach (LevelDbRecord record in reader.ReadRecords())
{
    // every record in the store, including superseded and deleted ones,
    // with sequence number, operation, and source file
}

Safety model

• Reading never takes the LevelDB lock and is safe while the owning app has the store open; slightly stale data is possible.
• Writing appends to the active log and requires the owning app to be closed.

Scope

Reading covers the full live file set (CURRENT, MANIFEST, write-ahead log, .ldb sstables with snappy compression). Writing is append-only: put/delete batches framed onto the active log, replayed by LevelDB/Chromium on next open - no sstable authoring, no compaction. The comparator is pluggable (bytewise by default). IndexedDB decoding is not included.

License

MIT