的EntityFramework,DbContextScope和精力 - 例外:的DbContext已配置的单元测试里面
问题描述:
我想要编写单元测试(与NUnit的)服务层,它的用途:的EntityFramework,DbContextScope和精力 - 例外:的DbContext已配置的单元测试里面
- 实体框架作为数据访问层
- DbContextScope用于管理DbContext生存期
我还使用Effort.EF6在单元测试中模拟DbContext。不幸的是,我找不到一种方法使DbContextScope与Effort兼容,这样我就可以正确地测试所有的情况。
概述代码
服务层包括其中做一些业务逻辑类(服务)。每种方法都被视为完整的交易,以context.SaveChanges()
结束。例如:
private IDbContextScopeFactory _dbContextScopeFactory;
public DepartmentsService(IDbContextScopeFactory dbContextScopeFactory)
{
_dbContextScopeFactory = dbContextScopeFactory;
}
public BusinessModel.Department Insert(BusinessModel.Department department)
{
using (var dbContextScope = _dbContextScopeFactory.Create())
{
// Validation
ValidateAndThrowOnFailure(department, new DepartmentAddValidator());
// Operation
DBModel.Department newDepartment = Mapper.Map<DBModel.Department>(department);
newDepartment.InsertDateUTC = DateTime.UtcNow;
dbContextScope.DbContexts.Get<DPSContext>().Departments.Add(newDepartment);
dbContextScope.SaveChanges();
return Mapper.Map<BusinessModel.Department>(newDepartment);
}
}
单元测试这样的方法,我做每个测试之前一些准备:
private IDepartmentsService _departmentsService;
private IDbContextScopeFactory _dbContextScopeFactory;
private IDbContextFactory _dbContextFactory;
private DBModel.DPSContext _dbEntities;
[SetUp]
public void ReInitializeTest()
{
// Setup DbContext with Effort.EF6
string connStr = ConfigurationManager.ConnectionStrings["DPSContext"].ConnectionString;
DbConnection connection = EntityConnectionFactory.CreateTransient(connStr);
_dbEntities = new DBModel.DPSContext(connection);
// Fill DbContext with in-memory data
_dbEntities.Departments.AddRange(DataInitializer.GetDepartments());
_dbEntities.SaveChanges();
// Mock IDbContextFactory so that it returns in-memory context
var contextFactoryMock = new Mock<IDbContextFactory>();
contextFactoryMock
.Setup(f => f.CreateDbContext<DBModel.DPSContext>())
.Returns(_dbEntities);
_dbContextFactory = contextFactoryMock.Object;
// Setup DbContextScopeFactory to use mocked context
_dbContextScopeFactory = new DbContextScopeFactory(_dbContextFactory);
_departmentsService = new DepartmentsService(_dbContextScopeFactory);
}
的测试和问题
下面是一个简单的单元测试:
[Test]
public void Insert_WhenValidModelPassed_ShouldInsertNewRecord()
{
// Given
BusinessModel.Department newDepartment = DataInitializer.GetExampleOfNewDepartment();
// When
_departmentsService.Insert(newDepartment);
// Then
Assert.AreEqual(3, _dbEntities.Departments.Count());
}
的问题是,测试失败,异常:
System.InvalidOperationException : The operation cannot be completed because the DbContext has been disposed.
似乎DbContextScope使用内部Insert
方法在内部部署分配上下文在using
块的末端,从而当被调用时的Assert
抛出异常。有没有人遇到过类似的问题,或者只是知道我应该怎么做才能成功地测试这种类似的情况?
答
对于任何遇到类似问题的人,我已经创建了一个有点肮脏但工作的解决方案(至少我希望如此)。除了我在这个问题中写的内容,我创建了一个从真实环境派生出来的类,并且使得方法没有...什么都不做。我还添加了每个测试结束时调用的方法RealDispose
。
public class TestableDPSContext : DBModel.DPSContext
{
public TestableDPSContext(DbConnection connection)
: base(connection)
{
}
protected override void Dispose(bool disposing)
{
// Do nothing
}
public void RealDispose(bool disposing)
{
// Invoke real dispose
base.Dispose(disposing);
}
}
[TearDown]
public void FinishTest()
{
_dbEntities.RealDispose(false);
}
也许有更好的解决方案,但现在看来,以解决DbContext
问题正在测试太早配置。