Handle DB nullability

Libraries/SPTarkov.Server.Core/Exceptions/Database/DatabaseNullException.cs

@@ -0,0 +1,10 @@
+namespace SPTarkov.Server.Core.Exceptions.Database;
+
+public class DatabaseNullException : Exception
+{
+    public DatabaseNullException(string message)
+        : base(message) { }
+
+    public DatabaseNullException(string message, Exception innerException)
+        : base(message, innerException) { }
+}

Libraries/SPTarkov.Server.Core/Exceptions/Database/DatabaseTablesAlreadySetException.cs

@@ -0,0 +1,10 @@
+namespace SPTarkov.Server.Core.Exceptions.Database;
+
+internal class DatabaseTablesAlreadySetException : Exception
+{
+    public DatabaseTablesAlreadySetException(string message)
+        : base(message) { }
+
+    public DatabaseTablesAlreadySetException(string message, Exception innerException)
+        : base(message, innerException) { }
+}

Libraries/SPTarkov.Server.Core/Models/Spt/Server/DatabaseTables.cs

@@ -10,23 +10,23 @@ public record DatabaseTables
     [JsonExtensionData]
     public Dictionary<string, object> ExtensionData { get; init; } = [];
 
-    public Bots.Bots Bots { get; set; }
+    public required Bots.Bots Bots { get; set; }
 
-    public Hideout.Hideout Hideout { get; set; }
+    public required Hideout.Hideout Hideout { get; set; }
 
-    public LocaleBase Locales { get; set; }
+    public required LocaleBase Locales { get; set; }
 
-    public Locations Locations { get; set; }
+    public required Locations Locations { get; set; }
 
-    public Match Match { get; set; }
+    public required Match Match { get; set; }
 
-    public Templates.Templates Templates { get; set; }
+    public required Templates.Templates Templates { get; set; }
 
-    public Dictionary<MongoId, Trader> Traders { get; set; }
+    public required Dictionary<MongoId, Trader> Traders { get; set; }
 
-    public Globals Globals { get; set; }
+    public required Globals Globals { get; set; }
 
-    public ServerBase Server { get; set; }
+    public required ServerBase Server { get; set; }
 
-    public SettingsBase Settings { get; set; }
+    public required SettingsBase Settings { get; set; }
 }

Libraries/SPTarkov.Server.Core/Servers/DatabaseServer.cs

@@ -1,4 +1,5 @@
 using SPTarkov.DI.Annotations;
+using SPTarkov.Server.Core.Exceptions.Database;
 using SPTarkov.Server.Core.Models.Spt.Server;
 
 namespace SPTarkov.Server.Core.Servers;
@@ -6,15 +7,37 @@ namespace SPTarkov.Server.Core.Servers;
 [Injectable(InjectionType.Singleton)]
 public class DatabaseServer
 {
-    protected DatabaseTables tableData = new();
+    protected DatabaseTables? TableData { get; private set; }
 
+    /// <summary>
+    /// Gets the database tables.
+    /// </summary>
+    /// <returns>The database tables if they have been initialized.</returns>
+    /// <exception cref="DatabaseNullException">Thrown when the database tables have not been initialized.</exception>
     public DatabaseTables GetTables()
     {
-        return tableData;
+        if (TableData is null)
+        {
+            throw new DatabaseNullException("Database tables have not been initialized!");
+        }
+
+        return TableData;
     }
 
-    public void SetTables(DatabaseTables tables)
+    /// <summary>
+    /// Sets the database tables for this instance. Can only be called once.
+    /// </summary>
+    /// <param name="tables">The database tables to set.</param>
+    /// <exception cref="DatabaseTablesAlreadySetException">Thrown if the database tables are already set.</exception>
+    internal void SetTables(DatabaseTables tables)
     {
-        tableData = tables;
+        if (TableData is null)
+        {
+            TableData = tables;
+        }
+        else
+        {
+            throw new DatabaseTablesAlreadySetException("The database is already initialized!");
+        }
     }
 }