How to test fluent migrations with an in-process migration runner and a in memory SQLite database

Question

I have just started to use FluentMigration for my current project. I wrote my first migration but I have some trouble writing a unit test for it.

Here is some sample code:

private ServiceProvider CreateServiceProvider()
{
    return new ServiceCollection()
        .AddLogging(lb => lb.AddFluentMigratorConsole())
        .AddFluentMigratorCore()
        .ConfigureRunner(
            builder => builder
                .AddSQLite()
                    .WithGlobalConnectionString("Data Source=:memory:;Version=3;New=True;")
                    .WithMigrationsIn(typeof(MigrationOne).Assembly))
            .BuildServiceProvider();
}

private void PerformMigrateUp(IServiceScope scope)
{
    var runner = scope.ServiceProvider.GetRequiredService<IMigrationRunner>();

    runner.MigrateUp(1);
}

[Test]
public void ShouldHaveTablesAfterMigrateUp()
{
    var provider = this.CreateServiceProvider();

    using (var scope = provider.CreateScope())
    {
        this.PerformMigrateUp(scope);

        // here I'd like to test if tables have been created in the database by the migration
    }
}

I don't know how (or if it is possible) to access the current database connection so I can perform a query. Any suggestions would be helpful. Thanks.

Answer 1

Ok, I found a solution. I have to use the Process method of the runner's processor to perform my own sql query.

It looks like this:

private ServiceProvider CreateServiceProvider()
{
    return new ServiceCollection()
        .AddLogging(lb => lb.AddFluentMigratorConsole())
        .AddFluentMigratorCore()
        .ConfigureRunner(
            builder => builder
                .AddSQLite()
                .WithGlobalConnectionString(@"Data Source=:memory:;Version=3;New=True;")
                .WithMigrationsIn(typeof(MigrationDate20181026113000Zero).Assembly))
        .BuildServiceProvider();
}

[Test]
public void ShouldHaveNewVersionAfterMigrateUp()
{
    var serviceProvider = this.CreateServiceProvider();
    var scope = serviceProvider.CreateScope();
    var runner = scope.ServiceProvider.GetRequiredService<IMigrationRunner>();

    runner.MigrateUp(1);

    string sqlStatement = "SELECT Description FROM VersionInfo";

    DataSet dataSet = runner.Processor.Read(sqlStatement, string.Empty);

    Assert.That(dataSet, Is.Not.Null);
    Assert.That(dataSet.Tables[0].Rows[0].ItemArray[0], Is.EqualTo("Migration1"));
}