Merge pull request #2101 from ZakFahey/general-devel

Fix config file access errors when starting up multiple TShock servers at once

CHANGELOG.md

@@ -14,6 +14,7 @@ This is the rolling changelog for TShock for Terraria. Use past tense when addin
 
 ## Upcoming changes
 * Added Gravedigger's Shovel support. (@Zennos)
+* You can now start up multiple TShock servers at once without getting a startup error. (@ZakFahey)
 
 ## TShock 4.4.0 (Pre-release 12)
 * Fixed various bugs related to Snake Charmer's Flute. (@rustly)  

TShockAPI/ConfigFile.cs

@@ -602,14 +602,21 @@ namespace TShockAPI
 		/// Reads a configuration file from a given path
 		/// </summary>
 		/// <param name="path">string path</param>
-		/// <returns>ConfigFile object</returns>
+		/// <param name="path">The path to the config file</param>
-		public static ConfigFile Read(string path)
+		/// <param name="anyMissingFields">
+		/// Whether the config object has any new files in it, meaning that the config file has to be
+		/// overwritten.
+		/// </param>
+		public static ConfigFile Read(string path, out bool anyMissingFields)
 		{
 			if (!File.Exists(path))
+			{
+				anyMissingFields = true;
 				return new ConfigFile();
+			}
 			using (var fs = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read))
 			{
-				return Read(fs);
+				return Read(fs, out anyMissingFields);
 			}
 		}
 
@@ -617,14 +624,17 @@ namespace TShockAPI
 		/// Reads the configuration file from a stream
 		/// </summary>
 		/// <param name="stream">stream</param>
+		/// <param name="anyMissingFields">
+		/// Whether the config object has any new fields in it, meaning that the config file has to be
+		/// overwritten.
+		/// </param>
 		/// <returns>ConfigFile object</returns>
-		public static ConfigFile Read(Stream stream)
+		public static ConfigFile Read(Stream stream, out bool anyMissingFields)
 		{
 			using (var sr = new StreamReader(stream))
 			{
-				var cf = JsonConvert.DeserializeObject<ConfigFile>(sr.ReadToEnd());
+				var cf = FileTools.LoadConfigAndCheckForMissingFields<ConfigFile>(sr.ReadToEnd(), out anyMissingFields);
-				if (ConfigRead != null)
+				ConfigRead?.Invoke(cf);
-					ConfigRead(cf);
 				return cf;
 			}
 		}

TShockAPI/DB/GroupManager.cs

@@ -389,7 +389,7 @@ namespace TShockAPI.DB
 						}
 
 						// Read the config file to prevent the possible loss of any unsaved changes
-						TShock.Config = ConfigFile.Read(FileTools.ConfigPath);
+						TShock.Config = ConfigFile.Read(FileTools.ConfigPath, out bool writeConfig);
 						if (TShock.Config.DefaultGuestGroupName == oldGroup.Name)
 						{
 							TShock.Config.DefaultGuestGroupName = newGroup.Name;
@@ -399,7 +399,10 @@ namespace TShockAPI.DB
 						{
 							TShock.Config.DefaultRegistrationGroupName = newGroup.Name;
 						}
-						TShock.Config.Write(FileTools.ConfigPath);
+						if (writeConfig)
+						{
+							TShock.Config.Write(FileTools.ConfigPath);
+						}
 
 						// We also need to check if any users belong to the old group and automatically apply changes
 						using (var command = db.CreateCommand())

TShockAPI/FileTools.cs

@@ -16,9 +16,13 @@ You should have received a copy of the GNU General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
 
+using Newtonsoft.Json;
+using Newtonsoft.Json.Linq;
 using System;
 using System.Collections.Generic;
+using System.Diagnostics;
 using System.IO;
+using System.Linq;
 using TShockAPI.ServerSideCharacters;
 
 namespace TShockAPI
@@ -103,20 +107,26 @@ namespace TShockAPI
 			CreateIfNot(MotdPath, MotdFormat);
 						
 			CreateIfNot(WhitelistPath);
+			bool writeConfig = true; // Default to true if the file doesn't exist
 			if (File.Exists(ConfigPath))
 			{
-				TShock.Config = ConfigFile.Read(ConfigPath);
+				TShock.Config = ConfigFile.Read(ConfigPath, out writeConfig);
-				// Add all the missing config properties in the json file
+			}
+			if (writeConfig)
+			{
+				// Add all the missing config properties in the json file
+				TShock.Config.Write(ConfigPath);
 			}
-			TShock.Config.Write(ConfigPath);
 
+			bool writeSSCConfig = true; // Default to true if the file doesn't exist
 			if (File.Exists(ServerSideCharacterConfigPath))
 			{
-				TShock.ServerSideCharacterConfig = ServerSideConfig.Read(ServerSideCharacterConfigPath);
+				TShock.ServerSideCharacterConfig =
-				// Add all the missing config properties in the json file
+					ServerSideConfig.Read(ServerSideCharacterConfigPath, out writeSSCConfig);
 			}
-			else
+			if (writeSSCConfig)
 			{
+				// Add all the missing config properties in the json file
 				TShock.ServerSideCharacterConfig = new ServerSideConfig
 				{
 					StartingInventory =
@@ -127,8 +137,8 @@ namespace TShockAPI
 							new NetItem(-16, 1, 0)
 						}
 				};
+				TShock.ServerSideCharacterConfig.Write(ServerSideCharacterConfigPath);
 			}
-			TShock.ServerSideCharacterConfig.Write(ServerSideCharacterConfigPath);
 		}
 
 		/// <summary>
@@ -163,5 +173,30 @@ namespace TShockAPI
 				return true;
 			}
 		}
+
+		/// <summary>
+		/// Parse some json text and also return whether any fields are missing from the json
+		/// </summary>
+		/// <typeparam name="T">The type of the config file object</typeparam>
+		/// <param name="json">The json text to parse</param>
+		/// <param name="anyMissingFields">Whether any fields are missing from the config</param>
+		/// <returns>The config object</returns>
+		internal static T LoadConfigAndCheckForMissingFields<T>(string json, out bool anyMissingFields)
+		{
+			JObject jObject = JObject.Parse(json);
+
+			anyMissingFields = false;
+			var configFields = new HashSet<string>(typeof(T).GetFields()
+				.Where(field => !field.IsStatic)
+				.Select(field => field.Name));
+			var jsonFields = new HashSet<string>(jObject
+				.Children()
+				.Select(field => field as JProperty)
+				.Where(field => field != null)
+				.Select(field => field.Name));
+			anyMissingFields = !configFields.SetEquals(jsonFields);
+
+			return jObject.ToObject<T>();
+		}
 	}
 }

TShockAPI/ServerSideCharacters/ServerSideConfig.cs

@@ -46,12 +46,22 @@ namespace TShockAPI.ServerSideCharacters
 		[Description("The starting default inventory for new SSC.")] 
 		public List<NetItem> StartingInventory = new List<NetItem>();
 
-		public static ServerSideConfig Read(string path)
+		/// <summary>
+		/// Reads a server-side configuration file from a given path
+		/// </summary>
+		/// <param name="path">The path to the config file</param>
+		/// <param name="anyMissingFields">
+		/// Whether the config object has any new fields in it, meaning that the config file has to be
+		/// overwritten.
+		/// </param>
+		/// <returns>ConfigFile object</returns>
+		public static ServerSideConfig Read(string path, out bool anyMissingFields)
 		{
-			using (var reader = new StreamReader(path))
+			using (var fileStream = new FileStream(path, FileMode.Open, FileAccess.Read, FileShare.Read))
+			using (var reader = new StreamReader(fileStream))
 			{
 				string txt = reader.ReadToEnd();
-				var config = JsonConvert.DeserializeObject<ServerSideConfig>(txt);
+				var config = FileTools.LoadConfigAndCheckForMissingFields<ServerSideConfig>(txt, out anyMissingFields);
 				return config;
 			}
 		}