public Func <Key, ValueTask <T> > CreateIndexMany <Key>(Func <T, IEnumerable <Key> > keySelector)
{
keySelector.NotNull(nameof(keySelector));
var index = new AtomicDictionary <Key, T>();
_upserters.Add(async transaction =>
{
foreach (var key in keySelector(transaction.Item))
{
index[key] = transaction.Item;
}
});
_deleters.Add(async item =>
{
foreach (var key in keySelector(item))
{
index.TryRemove(key);
}
});
return(async key =>
{
await Initialize();
return index.TryGetValue(key, out var item) ? item : default;
});
}
public Func <Key, ValueTask <T> > CreatePrimaryKey <Key>(Expression <Func <T, Key> > keySelectorExpression)
{
keySelectorExpression.NotNull(nameof(keySelectorExpression));
if (!_primaryKeyCreated.TrySet(true))
{
throw new Exception("Primary Key already exists");
}
var keySelector = keySelectorExpression.Compile();
var index = new AtomicDictionary <Key, T>();
_items = index.Values;
_upserters.Add(async transaction =>
{
var key = keySelector(transaction.Item);
if (key is null)
{
throw new Exception($"Upsert failed, key is null. Key: {keySelectorExpression.ToString()}, Document: {typeof(T).FullName}");
}
if (transaction.Write && _settings.DataDir.IsNotNullOrWhiteSpace())
{
var zipFile = GetFile(key.ToString());
var zipPath = zipFile.FullName;
using (await _fileLocks.GetOrAdd(zipPath).EnterAsync())
{
var tempFile = new FileInfo($"{zipPath}.temp");
using (var zip = ZipFile.Open(tempFile.FullName, ZipArchiveMode.Update))
{
var name = zipFile.Name.SkipLast(zipFile.Extension.Length).AsString();
using var stream = zip.CreateEntry(name, CompressionLevel.Optimal).Open();
await Jsonizer.SerializeAsync(transaction.Item, stream);
}
await tempFile.MoveAsync(zipFile);
}
}
else if (index.ContainsKey(key))
{
throw new Exception($"Duplicate entry found in db.json files. Key: {key}");
}
index[key] = transaction.Item;
});
_deleters.Add(async item =>
{
var key = keySelector(item);
if (key is null)
{
throw new Exception($"Delete failed, key is null. Key: {keySelectorExpression.ToString()}, Document: {typeof(T).FullName}");
}
if (index.TryRemove(key) && _settings.DataDir.IsNotNullOrWhiteSpace())
{
var zip = GetFile(key.ToString());
using (await _fileLocks.GetOrAdd(zip.FullName).EnterAsync())
await zip.DeleteAsync();
}
});
return(async key =>
{
await Initialize();
return index.TryGetValue(key, out var item) ? item : default;
});
}