Lock the database while executing Migrate()

Fixes #33731

src/EFCore.Relational/Migrations/HistoryRepository.cs

@@ -23,8 +23,6 @@ namespace Microsoft.EntityFrameworkCore.Migrations;
 ///         See <see href="https://aka.ms/efcore-docs-migrations">Database migrations</see> for more information and examples.
 ///     </para>
 /// </remarks>
-// TODO: Leverage query pipeline for GetAppliedMigrations
-// TODO: Leverage update pipeline for GetInsertScript & GetDeleteScript
 public abstract class HistoryRepository : IHistoryRepository
 {
     /// <summary>
@@ -122,15 +120,14 @@ protected virtual string ProductVersionColumnName
     /// </summary>
     /// <returns><see langword="true" /> if the table already exists, <see langword="false" /> otherwise.</returns>
     public virtual bool Exists()
-        => Dependencies.DatabaseCreator.Exists()
-            && InterpretExistsResult(
-                Dependencies.RawSqlCommandBuilder.Build(ExistsSql).ExecuteScalar(
-                    new RelationalCommandParameterObject(
-                        Dependencies.Connection,
-                        null,
-                        null,
-                        Dependencies.CurrentContext.Context,
-                        Dependencies.CommandLogger, CommandSource.Migrations)));
+        => InterpretExistsResult(
+            Dependencies.RawSqlCommandBuilder.Build(ExistsSql).ExecuteScalar(
+                new RelationalCommandParameterObject(
+                    Dependencies.Connection,
+                    null,
+                    null,
+                    Dependencies.CurrentContext.Context,
+                    Dependencies.CommandLogger, CommandSource.Migrations)));
 
     /// <summary>
     ///     Checks whether or not the history table exists.
@@ -142,16 +139,15 @@ public virtual bool Exists()
     /// </returns>
     /// <exception cref="OperationCanceledException">If the <see cref="CancellationToken" /> is canceled.</exception>
     public virtual async Task<bool> ExistsAsync(CancellationToken cancellationToken = default)
-        => await Dependencies.DatabaseCreator.ExistsAsync(cancellationToken).ConfigureAwait(false)
-            && InterpretExistsResult(
-                await Dependencies.RawSqlCommandBuilder.Build(ExistsSql).ExecuteScalarAsync(
-                    new RelationalCommandParameterObject(
-                        Dependencies.Connection,
-                        null,
-                        null,
-                        Dependencies.CurrentContext.Context,
-                        Dependencies.CommandLogger, CommandSource.Migrations),
-                    cancellationToken).ConfigureAwait(false));
+        => InterpretExistsResult(
+            await Dependencies.RawSqlCommandBuilder.Build(ExistsSql).ExecuteScalarAsync(
+                new RelationalCommandParameterObject(
+                    Dependencies.Connection,
+                    null,
+                    null,
+                    Dependencies.CurrentContext.Context,
+                    Dependencies.CommandLogger, CommandSource.Migrations),
+                cancellationToken).ConfigureAwait(false));
 
     /// <summary>
     ///     Interprets the result of executing <see cref="ExistsSql" />.
@@ -171,15 +167,49 @@ await Dependencies.RawSqlCommandBuilder.Build(ExistsSql).ExecuteScalarAsync(
     /// </summary>
     /// <returns>The SQL script.</returns>
     public virtual string GetCreateScript()
+        => string.Concat(GetCreateCommands().Select(c => c.CommandText));
+
+    /// <summary>
+    ///     Creates the history table.
+    /// </summary>
+    public virtual void Create()
+        => Dependencies.MigrationCommandExecutor.ExecuteNonQuery(GetCreateCommands(), Dependencies.Connection);
+
+    /// <summary>
+    ///     Creates the history table.
+    /// </summary>
+    public virtual Task CreateAsync(CancellationToken cancellationToken = default)
+        => Dependencies.MigrationCommandExecutor.ExecuteNonQueryAsync(GetCreateCommands(), Dependencies.Connection, cancellationToken);
+
+    /// <summary>
+    ///     Returns the migration commands that will create the history table.
+    /// </summary>
+    /// <returns>The migration commands that will create the history table.</returns>
+    protected virtual IReadOnlyList<MigrationCommand> GetCreateCommands()
     {
         var model = EnsureModel();
 
         var operations = Dependencies.ModelDiffer.GetDifferences(null, model.GetRelationalModel());
         var commandList = Dependencies.MigrationsSqlGenerator.Generate(operations, model);
-
-        return string.Concat(commandList.Select(c => c.CommandText));
+        return commandList;
     }
 
+    /// <summary>
+    ///     Gets an exclusive lock on the database.
+    /// </summary>
+    /// <param name="timeout">The time to wait for the lock before an exception is thrown.</param>
+    /// <returns>An object that can be disposed to release the lock.</returns>
+    public abstract IMigrationDatabaseLock GetDatabaseLock(TimeSpan timeout);
+
+    /// <summary>
+    ///     Gets an exclusive lock on the database.
+    /// </summary>
+    /// <param name="timeout">The time to wait for the lock before an exception is thrown.</param>
+    /// <param name="cancellationToken">A <see cref="CancellationToken" /> to observe while waiting for the task to complete.</param>
+    /// <returns>An object that can be disposed to release the lock.</returns>
+    /// <exception cref="OperationCanceledException">If the <see cref="CancellationToken" /> is canceled.</exception>
+    public abstract Task<IMigrationDatabaseLock> GetDatabaseLockAsync(TimeSpan timeout, CancellationToken cancellationToken = default);
+
     /// <summary>
     ///     Configures the entity type mapped to the history table.
     /// </summary>

src/EFCore.Relational/Migrations/HistoryRepositoryDependencies.cs

@@ -52,6 +52,7 @@ public HistoryRepositoryDependencies(
         IDbContextOptions options,
         IMigrationsModelDiffer modelDiffer,
         IMigrationsSqlGenerator migrationsSqlGenerator,
+        IMigrationCommandExecutor migrationCommandExecutor,
         ISqlGenerationHelper sqlGenerationHelper,
         IConventionSetBuilder conventionSetBuilder,
         ModelDependencies modelDependencies,
@@ -66,6 +67,7 @@ public HistoryRepositoryDependencies(
         Options = options;
         ModelDiffer = modelDiffer;
         MigrationsSqlGenerator = migrationsSqlGenerator;
+        MigrationCommandExecutor = migrationCommandExecutor;
         SqlGenerationHelper = sqlGenerationHelper;
         ConventionSetBuilder = conventionSetBuilder;
         ModelDependencies = modelDependencies;
@@ -110,6 +112,11 @@ public HistoryRepositoryDependencies(
     /// </summary>
     public ISqlGenerationHelper SqlGenerationHelper { get; init; }
 
+    /// <summary>
+    ///     The service for executing Migrations operations.
+    /// </summary>
+    public IMigrationCommandExecutor MigrationCommandExecutor { get; init; }
+
     /// <summary>
     ///     The core convention set to use when creating the model.
     /// </summary>

src/EFCore.Relational/Migrations/IHistoryRepository.cs

@@ -24,13 +24,13 @@ namespace Microsoft.EntityFrameworkCore.Migrations;
 public interface IHistoryRepository
 {
     /// <summary>
-    ///     Checks whether or not the history table exists.
+    ///     Checks whether the history table exists.
     /// </summary>
     /// <returns><see langword="true" /> if the table already exists, <see langword="false" /> otherwise.</returns>
     bool Exists();
 
     /// <summary>
-    ///     Checks whether or not the history table exists.
+    ///     Checks whether the history table exists.
     /// </summary>
     /// <param name="cancellationToken">A <see cref="CancellationToken" /> to observe while waiting for the task to complete.</param>
     /// <returns>
@@ -40,6 +40,22 @@ public interface IHistoryRepository
     /// <exception cref="OperationCanceledException">If the <see cref="CancellationToken" /> is canceled.</exception>
     Task<bool> ExistsAsync(CancellationToken cancellationToken = default);
 
+    /// <summary>
+    ///     Creates the history table.
+    /// </summary>
+    void Create();
+
+    /// <summary>
+    ///     Creates the history table.
+    /// </summary>
+    /// <param name="cancellationToken">A <see cref="CancellationToken" /> to observe while waiting for the task to complete.</param>
+    /// <returns>
+    ///     A task that represents the asynchronous operation. The task result contains
+    ///     <see langword="true" /> if the table already exists, <see langword="false" /> otherwise.
+    /// </returns>
+    /// <exception cref="OperationCanceledException">If the <see cref="CancellationToken" /> is canceled.</exception>
+    Task CreateAsync(CancellationToken cancellationToken = default);
+
     /// <summary>
     ///     Queries the history table for all migrations that have been applied.
     /// </summary>
@@ -58,6 +74,22 @@ public interface IHistoryRepository
     Task<IReadOnlyList<HistoryRow>> GetAppliedMigrationsAsync(
         CancellationToken cancellationToken = default);
 
+    /// <summary>
+    ///     Gets an exclusive lock on the database.
+    /// </summary>
+    /// <param name="timeout">The time to wait for the lock before an exception is thrown.</param>
+    /// <returns>An object that can be disposed to release the lock.</returns>
+    IMigrationDatabaseLock GetDatabaseLock(TimeSpan timeout);
+
+    /// <summary>
+    ///     Gets an exclusive lock on the database.
+    /// </summary>
+    /// <param name="timeout">The time to wait for the lock before an exception is thrown.</param>
+    /// <param name="cancellationToken">A <see cref="CancellationToken" /> to observe while waiting for the task to complete.</param>
+    /// <returns>An object that can be disposed to release the lock.</returns>
+    /// <exception cref="OperationCanceledException">If the <see cref="CancellationToken" /> is canceled.</exception>
+    Task<IMigrationDatabaseLock> GetDatabaseLockAsync(TimeSpan timeout, CancellationToken cancellationToken = default);
+
     /// <summary>
     ///     Generates a SQL script that will create the history table.
     /// </summary>

src/EFCore.Relational/Migrations/IMigrationDatabaseLock.cs

@@ -0,0 +1,11 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace Microsoft.EntityFrameworkCore.Migrations;
+
+/// <summary>
+///     Represents an exclusive lock on the database that is used to ensure that only one migration application can be run at a time.
+/// </summary>
+public interface IMigrationDatabaseLock : IDisposable, IAsyncDisposable
+{
+}