/// <summary>
/// Initializes a new instance of the <see cref="Database" /> class.
/// </summary>
/// <param name="dataPath">The database directory path.</param>
public Database(string dataPath = null)
{
if (String.IsNullOrWhiteSpace(dataPath))
{
var appPath = Path.GetDirectoryName(Assembly.GetEntryAssembly().Location);
dataPath = Path.Combine(appPath, DATA_DIRECTORY_NAME);
}
DataPath = dataPath;
EnsureDataDirectoryExists(DataPath);
_log.Info($"Data Path: {DataPath}");
IndexBasePath = Path.Combine(DataPath, INDEX_DIRECTORY_NAME);
EnsureIndexDirectoryExists(IndexBasePath);
_log.Info($"Index Base Path: {IndexBasePath}");
DocumentStorage = new LightningDocumentStorage(DataPath);
_collections = new ConcurrentDictionary<string, Collection>();
var persistedSchemas = DocumentStorage.GetAllAsync(Schema.COLLECTION_NAME).Result.Select(d => d.ToSchema());
foreach (var schema in persistedSchemas)
{
var collection = new Collection(schema, this);
_collections.TryAdd(schema.Name, collection);
}
var schemaPersistenceIntervalSeconds = Double.Parse(ConfigurationManager.AppSettings["Schema.PersistenceIntervalSeconds"] ?? "1");
_schemaPersistenceTimer = new Timer(_ => Task.Run(async () => await PersistSchemas().ConfigureAwait(false)), null, TimeSpan.FromSeconds(schemaPersistenceIntervalSeconds), TimeSpan.FromSeconds(schemaPersistenceIntervalSeconds));
}
/// <summary>
/// Persists the Schema of the specified Collection to a special _schemas Collection.
/// </summary>
/// <param name="collection">The collection.</param>
/// <returns></returns>
private async Task PersistSchema(Collection collection)
{
try
{
var liveSchemaDocument = collection.Schema.ToDocument();
var savedSchemaDocument = await this[Schema.COLLECTION_NAME].GetAsync(liveSchemaDocument._id.Value);
var isSchemaUpdated = false;
if (savedSchemaDocument == null)
{
await this[Schema.COLLECTION_NAME].InsertAsync(liveSchemaDocument);
isSchemaUpdated = true;
}
else
{
if (liveSchemaDocument != savedSchemaDocument)
{
await this[Schema.COLLECTION_NAME].UpdateAsync(liveSchemaDocument);
isSchemaUpdated = true;
}
}
if (isSchemaUpdated)
{
savedSchemaDocument = await this[Schema.COLLECTION_NAME].GetAsync(liveSchemaDocument._id.Value);
collection.Schema._id = savedSchemaDocument._id;
collection.Schema._createdTimestamp = savedSchemaDocument._createdTimestamp;
collection.Schema._modifiedTimestamp = savedSchemaDocument._modifiedTimestamp;
}
}
catch (Exception ex)
{
_log.Error(ex);
}
}
/// <summary>
/// Gets the <see cref="Collection"/> with the specified name.
/// </summary>
/// <value>
/// The <see cref="Collection"/> with the specified name.
/// </value>
/// <param name="name">The name of the Document Collection.</param>
/// <returns></returns>
public Collection this [string name]
{
get
{
if (String.IsNullOrWhiteSpace(name))
throw new ArgumentException("name cannot be null or blank");
Collection collection = null;
if (!_collections.ContainsKey(name))
{
lock (_collections)
{
if (!_collections.ContainsKey(name))
{
collection = new Collection(name, this);
_collections.TryAdd(name, collection);
}
}
}
_collections.TryGetValue(name, out collection);
if (collection == null || collection.IsDropped)
throw new InvalidOperationException($"The Document Collection '{name}' does not exist.");
return collection;
}
}