DatabaseModule.cs

using System;
using System.IO;
using System.Threading;
using System.Threading.Tasks;
using Waher.Runtime.Inventory;
 
namespace Waher.Persistence.LifeCycle
{
    [Singleton]
    public class DatabaseModule : IModule
    {
        private static IDatabaseProvider databaseProvider = null;
        private static ILedgerProvider ledgerProvider = null;
 
        public DatabaseModule()
        {
        }
 
        public async Task Start()
        {
            if (Database.HasProvider)
                await Database.Provider.Start();
 
            if (Ledger.HasProvider)
                await Ledger.Provider.Start();
 
            databaseProvider = null;
            ledgerProvider = null;
        }
 
        public async Task Stop()
        {
            if (Database.HasProvider)
            {
                databaseProvider = Database.Stop();
                await databaseProvider.Stop();
            }
 
            if (Ledger.HasProvider)
            {
                ledgerProvider = Ledger.Stop();
                await ledgerProvider.Stop();
            }
        }
 
        public static async Task Flush()
        {
            if (Database.HasProvider)
                await Database.Provider.Flush();
 
            if (Ledger.HasProvider)
                await Ledger.Provider.Flush();
 
            if (!(databaseProvider is null))
                await databaseProvider.Flush();
 
            if (!(ledgerProvider is null))
                await ledgerProvider.Flush();
        }
 
    }
}