F/226 simple data migrations system

Watchman.Discord/WatchmanBot.cs

@@ -24,7 +24,6 @@ public WatchmanBot(DiscordConfiguration configuration, IComponentContext context
 
         public WorkflowBuilder GetWorkflowBuilder(bool useDiscordNetClient = true)
         {
-            MongoConfiguration.Initialize();
             ExceptionHandlerService.DiscordConfiguration = this._configuration; //todo ioc
 
             return WorkflowBuilder

Watchman.DomainModel/Configuration/ConfigurationItem.cs

@@ -1,4 +1,6 @@
 using System;
+using System.Collections.Generic;
+using System.Linq;
 using Watchman.Integrations.Database;
 
 namespace Watchman.DomainModel.Configuration

Watchman.Integrations/Database/MongoDB/Migrations/.gitkeep

@@ -0,0 +1 @@
+

Watchman.Integrations/Database/MongoDB/MongoConfiguration.cs

@@ -1,7 +1,13 @@
-using MongoDB.Bson;
+using Microsoft.Extensions.Configuration;
+using MongoDB.Bson;
 using MongoDB.Bson.Serialization.Conventions;
+using MongoDB.Driver;
+using MongoDBMigrations;
+using Serilog;
 using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
+using System.Linq;
+using System.Reflection;
 
 namespace Watchman.Integrations.Database.MongoDB
 {
@@ -10,13 +16,14 @@ public static class MongoConfiguration
     {
         private static bool _initialized;
 
-        public static void Initialize()
+        public static void Initialize(IConfigurationRoot configuration)
         {
             if (_initialized)
             {
                 return;
             }
             RegisterConventions();
+            TryToMigrateDatabase(configuration);
             _initialized = true;
         }
 
@@ -25,14 +32,53 @@ private static void RegisterConventions()
             ConventionRegistry.Register("DevscordConventions", new MongoConventions(), x => true);
         }
 
-        private class MongoConventions : IConventionPack
+        private static void TryToMigrateDatabase(IConfigurationRoot configuration)
         {
-            public IEnumerable<IConvention> Conventions => new List<IConvention>
+            var connectionString = configuration.GetConnectionString("Mongo");
+            var databaseName = connectionString.Split('/').Last();
+            var assemblyForMigrations = Assembly.GetExecutingAssembly();
+
+            if (ShouldNotDoMigrations(connectionString, databaseName, assemblyForMigrations))
+            {
+                return;
+            }
+
+            var result = new MigrationEngine()
+                .UseDatabase(connectionString, databaseName)
+                .UseAssembly(assemblyForMigrations)
+                .UseSchemeValidation(enabled: false)
+                .UseProgressHandler(context =>
+                    Log.Information($@"The migration with name ""{context.MigrationName}"" from {context.TargetVersion} version was processed as {context.CurrentNumber} from all {context.TotalCount} migrations."))
+                .Run();
+
+            if (!result.Success)
             {
-                new IgnoreExtraElementsConvention(true),
-                new EnumRepresentationConvention(BsonType.String),
-                new CamelCaseElementNameConvention()
-            };
+                // TODO: Do something when migrations throw exceptions.
+            }
+
+            Log.Information($"The current version of the database after data migrations is {result.CurrentVersion}.");
+        }
+
+        private static bool ShouldNotDoMigrations(string connectionString, string databaseName, Assembly assemblyForMigrations)
+        {
+            var migrationInterfaceType = typeof(IMigration);
+            var areNotThereMigrations = assemblyForMigrations.GetTypes()
+                .All(t => t.GetInterfaces().Contains(migrationInterfaceType) == false);
+
+            if (areNotThereMigrations)
+            {
+                Log.Warning("The app doesn't see any migration to use.");
+            }
+
+            var mongoClient = new MongoClient(new MongoUrl(connectionString));
+            var isNotDatabaseExisting = mongoClient.ListDatabaseNames().ToList().All(x => x != databaseName);
+
+            if (isNotDatabaseExisting)
+            {
+                Log.Warning("The database doesn't exist yet (so data migrations won't be used).");
+            }
+
+            return areNotThereMigrations || isNotDatabaseExisting;
         }
     }
 }

Watchman.Integrations/Database/MongoDB/MongoConventions.cs

@@ -0,0 +1,16 @@
+using MongoDB.Bson;
+using MongoDB.Bson.Serialization.Conventions;
+using System.Collections.Generic;
+
+namespace Watchman.Integrations.Database.MongoDB
+{
+    internal class MongoConventions : IConventionPack
+    {
+        public IEnumerable<IConvention> Conventions => new List<IConvention>
+        {
+            new IgnoreExtraElementsConvention(true),
+            new EnumRepresentationConvention(BsonType.String),
+            new CamelCaseElementNameConvention()
+        };
+    }
+}

Watchman.Integrations/Watchman.Integrations.csproj

@@ -22,8 +22,10 @@
     <PackageReference Include="Discord.Net.WebSocket" Version="3.4.1" />
     <PackageReference Include="HtmlAgilityPack" Version="1.11.42" />
     <PackageReference Include="LiteDB" Version="5.0.11" />
+    <PackageReference Include="Microsoft.CodeAnalysis" Version="4.0.0" />
     <PackageReference Include="Microsoft.Extensions.Configuration.Abstractions" Version="6.0.0" />
     <PackageReference Include="MongoDB.Driver" Version="2.15.0" />
+    <PackageReference Include="MongoDBMigrations" Version="2.2.0" />
     <PackageReference Include="Serilog" Version="2.10.0" />
     <PackageReference Include="Serilog.Enrichers.Environment" Version="2.2.0" />
     <PackageReference Include="Serilog.Enrichers.Process" Version="2.0.2" />

Watchman.Web/Program.cs

@@ -14,9 +14,9 @@ public class Program
     {
         public static void Main(string[] args)
         {
-            MongoConfiguration.Initialize();
             var configuration = GetConfiguration();
             Log.Logger = SerilogInitializer.Initialize(configuration);
+            MongoConfiguration.Initialize(configuration);
             CreateHostBuilder(args, configuration).Build().Run();
         }