Optimize OpenIddictMongoDbContext to avoid using an async state machine when the database was already instantiated

src/OpenIddict.MongoDb/OpenIddictMongoDbContext.cs

@@ -40,69 +40,74 @@ namespace OpenIddict.MongoDb
         /// A <see cref="ValueTask{TResult}"/> that can be used to monitor the
         /// asynchronous operation, whose result returns the MongoDB database.
         /// </returns>
-        public async ValueTask<IMongoDatabase> GetDatabaseAsync(CancellationToken cancellationToken)
+        public ValueTask<IMongoDatabase> GetDatabaseAsync(CancellationToken cancellationToken)
         {
             if (_database != null)
             {
-                return _database;
+                return new ValueTask<IMongoDatabase>(_database);
             }
 
-            var options = _options.CurrentValue;
-            if (options == null)
+            async Task<IMongoDatabase> ExecuteAsync()
             {
-                throw new InvalidOperationException("The OpenIddict MongoDB options cannot be retrieved.");
-            }
-
-            var database = options.Database;
-            if (database == null)
-            {
-                database = _provider.GetService<IMongoDatabase>();
-            }
+                var options = _options.CurrentValue;
+                if (options == null)
+                {
+                    throw new InvalidOperationException("The OpenIddict MongoDB options cannot be retrieved.");
+                }
 
-            if (database == null)
-            {
-                throw new InvalidOperationException(new StringBuilder()
-                    .AppendLine("No suitable MongoDB database service can be found.")
-                    .Append("To configure the OpenIddict MongoDB stores to use a specific database, use ")
-                    .Append("'services.AddOpenIddict().AddCore().UseMongoDb().UseDatabase()' or register an ")
-                    .Append("'IMongoDatabase' in the dependency injection container in 'ConfigureServices()'.")
-                    .ToString());
-            }
+                var database = options.Database;
+                if (database == null)
+                {
+                    database = _provider.GetService<IMongoDatabase>();
+                }
 
-            // Note: the cancellation token passed as a parameter is deliberately not used here to ensure
-            // the cancellation of a single store operation doesn't prevent the indexes from being created.
-            var applications = database.GetCollection<OpenIddictApplication>(options.ApplicationsCollectionName);
-            await applications.Indexes.CreateOneAsync(
-                Builders<OpenIddictApplication>.IndexKeys.Ascending(application => application.ClientId),
-                new CreateIndexOptions
+                if (database == null)
                 {
-                    Unique = true
-                });
+                    throw new InvalidOperationException(new StringBuilder()
+                        .AppendLine("No suitable MongoDB database service can be found.")
+                        .Append("To configure the OpenIddict MongoDB stores to use a specific database, use ")
+                        .Append("'services.AddOpenIddict().AddCore().UseMongoDb().UseDatabase()' or register an ")
+                        .Append("'IMongoDatabase' in the dependency injection container in 'ConfigureServices()'.")
+                        .ToString());
+                }
 
-            await applications.Indexes.CreateOneAsync(
-                Builders<OpenIddictApplication>.IndexKeys.Ascending(application => application.PostLogoutRedirectUris));
+                // Note: the cancellation token passed as a parameter is deliberately not used here to ensure
+                // the cancellation of a single store operation doesn't prevent the indexes from being created.
+                var applications = database.GetCollection<OpenIddictApplication>(options.ApplicationsCollectionName);
+                await applications.Indexes.CreateOneAsync(
+                    Builders<OpenIddictApplication>.IndexKeys.Ascending(application => application.ClientId),
+                    new CreateIndexOptions
+                    {
+                        Unique = true
+                    });
 
-            await applications.Indexes.CreateOneAsync(
-                Builders<OpenIddictApplication>.IndexKeys.Ascending(application => application.RedirectUris));
+                await applications.Indexes.CreateOneAsync(
+                    Builders<OpenIddictApplication>.IndexKeys.Ascending(application => application.PostLogoutRedirectUris));
 
-            var scopes = database.GetCollection<OpenIddictScope>(options.ScopesCollectionName);
-            await scopes.Indexes.CreateOneAsync(
-                Builders<OpenIddictScope>.IndexKeys.Ascending(scope => scope.Name),
-                new CreateIndexOptions
-                {
-                    Unique = true
-                });
+                await applications.Indexes.CreateOneAsync(
+                    Builders<OpenIddictApplication>.IndexKeys.Ascending(application => application.RedirectUris));
 
-            var tokens = database.GetCollection<OpenIddictToken>(options.TokensCollectionName);
-            await tokens.Indexes.CreateOneAsync(
-                Builders<OpenIddictToken>.IndexKeys.Ascending(token => token.ReferenceId),
-                new CreateIndexOptions<OpenIddictToken>
-                {
-                    PartialFilterExpression = Builders<OpenIddictToken>.Filter.Exists(token => token.ReferenceId),
-                    Unique = true
-                });
+                var scopes = database.GetCollection<OpenIddictScope>(options.ScopesCollectionName);
+                await scopes.Indexes.CreateOneAsync(
+                    Builders<OpenIddictScope>.IndexKeys.Ascending(scope => scope.Name),
+                    new CreateIndexOptions
+                    {
+                        Unique = true
+                    });
+
+                var tokens = database.GetCollection<OpenIddictToken>(options.TokensCollectionName);
+                await tokens.Indexes.CreateOneAsync(
+                    Builders<OpenIddictToken>.IndexKeys.Ascending(token => token.ReferenceId),
+                    new CreateIndexOptions<OpenIddictToken>
+                    {
+                        PartialFilterExpression = Builders<OpenIddictToken>.Filter.Exists(token => token.ReferenceId),
+                        Unique = true
+                    });
+
+                return _database = database;
+            }
 
-            return _database = database;
+            return new ValueTask<IMongoDatabase>(ExecuteAsync());
         }
     }
 }

src/OpenIddict.MongoDb/Stores/OpenIddictApplicationStore.cs

@@ -794,6 +794,7 @@ namespace OpenIddict.MongoDb
 
             // Generate a new concurrency token and attach it
             // to the application before persisting the changes.
+            var timestamp = application.ConcurrencyToken;
             application.ConcurrencyToken = Guid.NewGuid().ToString();
 
             var database = await Context.GetDatabaseAsync(cancellationToken);
@@ -801,7 +802,7 @@ namespace OpenIddict.MongoDb
 
             if ((await collection.ReplaceOneAsync(entity =>
                 entity.Id == application.Id &&
-                entity.ConcurrencyToken == application.ConcurrencyToken, application, null, cancellationToken)).MatchedCount == 0)
+                entity.ConcurrencyToken == timestamp, application, null, cancellationToken)).MatchedCount == 0)
             {
                 throw new OpenIddictException(OpenIddictConstants.Exceptions.ConcurrencyError, new StringBuilder()
                     .AppendLine("The application was concurrently updated and cannot be persisted in its current state.")

src/OpenIddict.MongoDb/Stores/OpenIddictAuthorizationStore.cs

@@ -745,6 +745,7 @@ namespace OpenIddict.MongoDb
 
             // Generate a new concurrency token and attach it
             // to the authorization before persisting the changes.
+            var timestamp = authorization.ConcurrencyToken;
             authorization.ConcurrencyToken = Guid.NewGuid().ToString();
 
             var database = await Context.GetDatabaseAsync(cancellationToken);
@@ -752,7 +753,7 @@ namespace OpenIddict.MongoDb
 
             if ((await collection.ReplaceOneAsync(entity =>
                 entity.Id == authorization.Id &&
-                entity.ConcurrencyToken == authorization.ConcurrencyToken, authorization, null, cancellationToken)).MatchedCount == 0)
+                entity.ConcurrencyToken == timestamp, authorization, null, cancellationToken)).MatchedCount == 0)
             {
                 throw new OpenIddictException(OpenIddictConstants.Exceptions.ConcurrencyError, new StringBuilder()
                     .AppendLine("The authorization was concurrently updated and cannot be persisted in its current state.")

src/OpenIddict.MongoDb/Stores/OpenIddictScopeStore.cs

@@ -591,6 +591,7 @@ namespace OpenIddict.MongoDb
 
             // Generate a new concurrency token and attach it
             // to the scope before persisting the changes.
+            var timestamp = scope.ConcurrencyToken;
             scope.ConcurrencyToken = Guid.NewGuid().ToString();
 
             var database = await Context.GetDatabaseAsync(cancellationToken);
@@ -598,7 +599,7 @@ namespace OpenIddict.MongoDb
 
             if ((await collection.ReplaceOneAsync(entity =>
                 entity.Id == scope.Id &&
-                entity.ConcurrencyToken == scope.ConcurrencyToken, scope, null, cancellationToken)).MatchedCount == 0)
+                entity.ConcurrencyToken == timestamp, scope, null, cancellationToken)).MatchedCount == 0)
             {
                 throw new OpenIddictException(OpenIddictConstants.Exceptions.ConcurrencyError, new StringBuilder()
                     .AppendLine("The scope was concurrently updated and cannot be persisted in its current state.")

src/OpenIddict.MongoDb/Stores/OpenIddictTokenStore.cs

@@ -855,6 +855,7 @@ namespace OpenIddict.MongoDb
 
             // Generate a new concurrency token and attach it
             // to the token before persisting the changes.
+            var timestamp = token.ConcurrencyToken;
             token.ConcurrencyToken = Guid.NewGuid().ToString();
 
             var database = await Context.GetDatabaseAsync(cancellationToken);
@@ -862,7 +863,7 @@ namespace OpenIddict.MongoDb
 
             if ((await collection.ReplaceOneAsync(entity =>
                 entity.Id == token.Id &&
-                entity.ConcurrencyToken == token.ConcurrencyToken, token, null, cancellationToken)).MatchedCount == 0)
+                entity.ConcurrencyToken == timestamp, token, null, cancellationToken)).MatchedCount == 0)
             {
                 throw new OpenIddictException(OpenIddictConstants.Exceptions.ConcurrencyError, new StringBuilder()
                     .AppendLine("The token was concurrently updated and cannot be persisted in its current state.")