From 66055f1d7c42ac4a285b33c3770ce0559aaac34d Mon Sep 17 00:00:00 2001
From: Kyle Spearrin <kspearrin@users.noreply.github.com>
Date: Tue, 2 Jun 2020 09:13:57 -0400
Subject: [PATCH] Singleton LiteDatabase (#946)

* update litedb. initialize db as a static singleton instance.

* dont need to dispose anymore
---
 src/Core/Core.csproj                      |  2 +-
 src/Core/Services/LiteDbStorageService.cs | 20 +++++++++++---------
 2 files changed, 12 insertions(+), 10 deletions(-)

diff --git a/src/Core/Core.csproj b/src/Core/Core.csproj
index 729d4e82d..923688580 100644
--- a/src/Core/Core.csproj
+++ b/src/Core/Core.csproj
@@ -24,7 +24,7 @@
 
   <ItemGroup>
     <PackageReference Include="CsvHelper" Version="15.0.5" />
-    <PackageReference Include="LiteDB" Version="5.0.4" />
+    <PackageReference Include="LiteDB" Version="5.0.8" />
     <PackageReference Include="Newtonsoft.Json" Version="12.0.3" />
     <PackageReference Include="PCLCrypto" Version="2.0.147" />
   </ItemGroup>
diff --git a/src/Core/Services/LiteDbStorageService.cs b/src/Core/Services/LiteDbStorageService.cs
index 7ba9617f5..9fcdcb3a7 100644
--- a/src/Core/Services/LiteDbStorageService.cs
+++ b/src/Core/Services/LiteDbStorageService.cs
@@ -2,14 +2,16 @@
 using LiteDB;
 using Newtonsoft.Json;
 using Newtonsoft.Json.Serialization;
-using System;
 using System.Linq;
 using System.Threading.Tasks;
 
 namespace Bit.Core.Services
 {
-    public class LiteDbStorageService : IStorageService, IDisposable
+    public class LiteDbStorageService : IStorageService
     {
+        private static LiteDatabase _db;
+        private static readonly object _lock = new object();
+
         private readonly JsonSerializerSettings _jsonSettings = new JsonSerializerSettings
         {
             ContractResolver = new CamelCasePropertyNamesContractResolver()
@@ -17,7 +19,6 @@ namespace Bit.Core.Services
         private readonly string _dbPath;
         private ILiteCollection<JsonItem> _collection;
         private Task _initTask;
-        private LiteDatabase _db;
 
         public LiteDbStorageService(string dbPath)
         {
@@ -38,7 +39,13 @@ namespace Bit.Core.Services
             {
                 try
                 {
-                    _db = new LiteDatabase($"Filename={_dbPath};Upgrade=true;");
+                    lock (_lock)
+                    {
+                        if (_db == null)
+                        {
+                            _db = new LiteDatabase($"Filename={_dbPath};Upgrade=true;");
+                        }
+                    }
                     _collection = _db.GetCollection<JsonItem>("json_items");
                 }
                 finally
@@ -73,11 +80,6 @@ namespace Bit.Core.Services
             _collection.DeleteMany(i => i.Id == key);
         }
 
-        public void Dispose()
-        {
-            _db?.Dispose();
-        }
-
         private class JsonItem
         {
             public JsonItem() { }