Create MongoDbContext which provides the IMongoDatabase to other cont…

…exts.

Make it a scoped service so only 1 MongoClient is created per request. Use that to expose transactions which are now shared across all Repos.

Backend/Contexts/BannerContext.cs

@@ -1,22 +1,20 @@
 using System.Diagnostics.CodeAnalysis;
 using BackendFramework.Interfaces;
 using BackendFramework.Models;
-using Microsoft.Extensions.Options;
 using MongoDB.Driver;
 
 namespace BackendFramework.Contexts
 {
     [ExcludeFromCodeCoverage]
     public class BannerContext : IBannerContext
     {
-        private readonly IMongoDatabase _db;
+        private readonly IMongoDbContext _mongoDbContext;
 
-        public BannerContext(IOptions<Startup.Settings> options)
+        public BannerContext(IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
         }
 
-        public IMongoCollection<Banner> Banners => _db.GetCollection<Banner>("BannerCollection");
+        public IMongoCollection<Banner> Banners => _mongoDbContext.Db.GetCollection<Banner>("BannerCollection");
     }
 }

Backend/Contexts/MergeBlacklistContext.cs

@@ -1,23 +1,20 @@
 using System.Diagnostics.CodeAnalysis;
 using BackendFramework.Interfaces;
 using BackendFramework.Models;
-using Microsoft.Extensions.Options;
 using MongoDB.Driver;
 
 namespace BackendFramework.Contexts
 {
     [ExcludeFromCodeCoverage]
     public class MergeBlacklistContext : IMergeBlacklistContext
     {
-        private readonly IMongoDatabase _db;
-
-        public MergeBlacklistContext(IOptions<Startup.Settings> options)
+        private readonly IMongoDbContext _mongoDbContext;
+        public MergeBlacklistContext(IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
         }
 
-        public IMongoCollection<MergeWordSet> MergeBlacklist => _db.GetCollection<MergeWordSet>(
+        public IMongoCollection<MergeWordSet> MergeBlacklist => _mongoDbContext.Db.GetCollection<MergeWordSet>(
             "MergeBlacklistCollection");
     }
 }

Backend/Contexts/MergeGraylistContext.cs

@@ -1,23 +1,20 @@
 using System.Diagnostics.CodeAnalysis;
 using BackendFramework.Interfaces;
 using BackendFramework.Models;
-using Microsoft.Extensions.Options;
 using MongoDB.Driver;
 
 namespace BackendFramework.Contexts
 {
     [ExcludeFromCodeCoverage]
     public class MergeGraylistContext : IMergeGraylistContext
     {
-        private readonly IMongoDatabase _db;
-
-        public MergeGraylistContext(IOptions<Startup.Settings> options)
+        private readonly IMongoDbContext _mongoDbContext;
+        public MergeGraylistContext(IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
         }
 
-        public IMongoCollection<MergeWordSet> MergeGraylist => _db.GetCollection<MergeWordSet>(
+        public IMongoCollection<MergeWordSet> MergeGraylist => _mongoDbContext.Db.GetCollection<MergeWordSet>(
             "MergeGraylistCollection");
     }
 }

Backend/Contexts/MongoDbContext.cs

@@ -0,0 +1,47 @@
+using System.Threading.Tasks;
+using BackendFramework.Interfaces;
+using Microsoft.Extensions.Options;
+using MongoDB.Driver;
+
+namespace BackendFramework.Contexts;
+
+public class MongoDbContext : IMongoDbContext
+{
+    public IMongoDatabase Db { get; }
+
+    public MongoDbContext(IOptions<Startup.Settings> options)
+    {
+        var client = new MongoClient(options.Value.ConnectionString);
+        Db = client.GetDatabase(options.Value.CombineDatabase);
+    }
+
+    public async Task<IMongoTransaction> BeginTransaction()
+    {
+        return new MongoTransactionWrapper(await Db.Client.StartSessionAsync());
+    }
+
+    private class MongoTransactionWrapper : IMongoTransaction
+    {
+        private readonly IClientSessionHandle _session;
+
+        public MongoTransactionWrapper(IClientSessionHandle session)
+        {
+            _session = session;
+        }
+
+        public Task CommitTransactionAsync()
+        {
+            return _session.CommitTransactionAsync();
+        }
+
+        public Task AbortTransactionAsync()
+        {
+            return _session.AbortTransactionAsync();
+        }
+
+        public void Dispose()
+        {
+            _session.Dispose();
+        }
+    }
+}

Backend/Contexts/PasswordResetContext.cs

@@ -10,17 +10,16 @@ namespace BackendFramework.Contexts
     [ExcludeFromCodeCoverage]
     public class PasswordResetContext : IPasswordResetContext
     {
-        private readonly IMongoDatabase _db;
+        private readonly IMongoDbContext _mongoDbContext;
         public int ExpireTime { get; }
 
-        public PasswordResetContext(IOptions<Startup.Settings> options)
+        public PasswordResetContext(IOptions<Startup.Settings> options, IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
             ExpireTime = options.Value.PassResetExpireTime;
         }
 
-        private IMongoCollection<PasswordReset> PasswordResets => _db.GetCollection<PasswordReset>(
+        private IMongoCollection<PasswordReset> PasswordResets => _mongoDbContext.Db.GetCollection<PasswordReset>(
             "PasswordResetCollection");
 
         public Task ClearAll(string email)

Backend/Contexts/ProjectContext.cs

@@ -1,22 +1,19 @@
 using System.Diagnostics.CodeAnalysis;
 using BackendFramework.Interfaces;
 using BackendFramework.Models;
-using Microsoft.Extensions.Options;
 using MongoDB.Driver;
 
 namespace BackendFramework.Contexts
 {
     [ExcludeFromCodeCoverage]
     public class ProjectContext : IProjectContext
     {
-        private readonly IMongoDatabase _db;
-
-        public ProjectContext(IOptions<Startup.Settings> options)
+        private readonly IMongoDbContext _mongoDbContext;
+        public ProjectContext(IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
         }
 
-        public IMongoCollection<Project> Projects => _db.GetCollection<Project>("ProjectsCollection");
+        public IMongoCollection<Project> Projects => _mongoDbContext.Db.GetCollection<Project>("ProjectsCollection");
     }
 }

Backend/Contexts/SemanticDomainContext.cs

@@ -1,23 +1,20 @@
 using System.Diagnostics.CodeAnalysis;
 using BackendFramework.Interfaces;
 using BackendFramework.Models;
-using Microsoft.Extensions.Options;
 using MongoDB.Driver;
 
 namespace BackendFramework.Contexts
 {
     [ExcludeFromCodeCoverage]
     public class SemanticDomainContext : ISemanticDomainContext
     {
-        private readonly IMongoDatabase _db;
-
-        public SemanticDomainContext(IOptions<Startup.Settings> options)
+        private readonly IMongoDbContext _mongoDbContext;
+        public SemanticDomainContext(IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
         }
 
-        public IMongoCollection<SemanticDomainTreeNode> SemanticDomains => _db.GetCollection<SemanticDomainTreeNode>("SemanticDomainTree");
-        public IMongoCollection<SemanticDomainFull> FullSemanticDomains => _db.GetCollection<SemanticDomainFull>("SemanticDomains");
+        public IMongoCollection<SemanticDomainTreeNode> SemanticDomains => _mongoDbContext.Db.GetCollection<SemanticDomainTreeNode>("SemanticDomainTree");
+        public IMongoCollection<SemanticDomainFull> FullSemanticDomains => _mongoDbContext.Db.GetCollection<SemanticDomainFull>("SemanticDomains");
     }
 }

Backend/Contexts/SpeakerContext.cs

@@ -1,22 +1,20 @@
 using System.Diagnostics.CodeAnalysis;
 using BackendFramework.Interfaces;
 using BackendFramework.Models;
-using Microsoft.Extensions.Options;
 using MongoDB.Driver;
 
 namespace BackendFramework.Contexts
 {
     [ExcludeFromCodeCoverage]
     public class SpeakerContext : ISpeakerContext
     {
-        private readonly IMongoDatabase _db;
-
-        public SpeakerContext(IOptions<Startup.Settings> options)
+        private readonly IMongoDbContext _mongoDbContext;
+        
+        public SpeakerContext(IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
         }
 
-        public IMongoCollection<Speaker> Speakers => _db.GetCollection<Speaker>("SpeakersCollection");
+        public IMongoCollection<Speaker> Speakers => _mongoDbContext.Db.GetCollection<Speaker>("SpeakersCollection");
     }
 }

Backend/Contexts/UserContext.cs

@@ -1,22 +1,19 @@
 using System.Diagnostics.CodeAnalysis;
 using BackendFramework.Interfaces;
 using BackendFramework.Models;
-using Microsoft.Extensions.Options;
 using MongoDB.Driver;
 
 namespace BackendFramework.Contexts
 {
     [ExcludeFromCodeCoverage]
     public class UserContext : IUserContext
     {
-        private readonly IMongoDatabase _db;
-
-        public UserContext(IOptions<Startup.Settings> options)
+        private readonly IMongoDbContext _mongoDbContext;
+        public UserContext(IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
         }
 
-        public IMongoCollection<User> Users => _db.GetCollection<User>("UsersCollection");
+        public IMongoCollection<User> Users => _mongoDbContext.Db.GetCollection<User>("UsersCollection");
     }
 }

Backend/Contexts/UserEditContext.cs

@@ -1,22 +1,19 @@
 using System.Diagnostics.CodeAnalysis;
 using BackendFramework.Interfaces;
 using BackendFramework.Models;
-using Microsoft.Extensions.Options;
 using MongoDB.Driver;
 
 namespace BackendFramework.Contexts
 {
     [ExcludeFromCodeCoverage]
     public class UserEditContext : IUserEditContext
     {
-        private readonly IMongoDatabase _db;
-
-        public UserEditContext(IOptions<Startup.Settings> options)
+        private readonly IMongoDbContext _mongoDbContext;
+        public UserEditContext(IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
         }
 
-        public IMongoCollection<UserEdit> UserEdits => _db.GetCollection<UserEdit>("UserEditsCollection");
+        public IMongoCollection<UserEdit> UserEdits => _mongoDbContext.Db.GetCollection<UserEdit>("UserEditsCollection");
     }
 }

Backend/Contexts/UserRoleContext.cs

@@ -1,22 +1,19 @@
 using System.Diagnostics.CodeAnalysis;
 using BackendFramework.Interfaces;
 using BackendFramework.Models;
-using Microsoft.Extensions.Options;
 using MongoDB.Driver;
 
 namespace BackendFramework.Contexts
 {
     [ExcludeFromCodeCoverage]
     public class UserRoleContext : IUserRoleContext
     {
-        private readonly IMongoDatabase _db;
-
-        public UserRoleContext(IOptions<Startup.Settings> options)
+        private readonly IMongoDbContext _mongoDbContext;
+        public UserRoleContext(IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
         }
 
-        public IMongoCollection<UserRole> UserRoles => _db.GetCollection<UserRole>("UserRolesCollection");
+        public IMongoCollection<UserRole> UserRoles => _mongoDbContext.Db.GetCollection<UserRole>("UserRolesCollection");
     }
 }

Backend/Contexts/WordContext.cs

@@ -1,23 +1,20 @@
 using System.Diagnostics.CodeAnalysis;
 using BackendFramework.Interfaces;
 using BackendFramework.Models;
-using Microsoft.Extensions.Options;
 using MongoDB.Driver;
 
 namespace BackendFramework.Contexts
 {
     [ExcludeFromCodeCoverage]
     public class WordContext : IWordContext
     {
-        private readonly IMongoDatabase _db;
-
-        public WordContext(IOptions<Startup.Settings> options)
+        private readonly IMongoDbContext _mongoDbContext;
+        public WordContext(IMongoDbContext mongoDbContext)
         {
-            var client = new MongoClient(options.Value.ConnectionString);
-            _db = client.GetDatabase(options.Value.CombineDatabase);
+            _mongoDbContext = mongoDbContext;
         }
 
-        public IMongoCollection<Word> Words => _db.GetCollection<Word>("WordsCollection");
-        public IMongoCollection<Word> Frontier => _db.GetCollection<Word>("FrontierCollection");
+        public IMongoCollection<Word> Words => _mongoDbContext.Db.GetCollection<Word>("WordsCollection");
+        public IMongoCollection<Word> Frontier => _mongoDbContext.Db.GetCollection<Word>("FrontierCollection");
     }
 }

Backend/Interfaces/IMongoDbContext.cs

@@ -0,0 +1,17 @@
+using System;
+using System.Threading.Tasks;
+using MongoDB.Driver;
+
+namespace BackendFramework.Interfaces;
+
+public interface IMongoDbContext
+{
+    IMongoDatabase Db { get; }
+    Task<IMongoTransaction> BeginTransaction();
+}
+
+public interface IMongoTransaction : IDisposable
+{
+    Task CommitTransactionAsync();
+    Task AbortTransactionAsync();
+}

Backend/Startup.cs

@@ -287,6 +287,9 @@ public void ConfigureServices(IServiceCollection services)
             services.AddTransient<IWordContext, WordContext>();
             services.AddTransient<IWordRepository, WordRepository>();
             services.AddTransient<IWordService, WordService>();
+
+            // mongo context, scoped so it is shared across a single request
+            services.AddScoped<IMongoDbContext, MongoDbContext>();
         }
 
         /// <summary> This method gets called by the runtime. Use this method to configure the HTTP request pipeline.