c#-使用Moq模拟对MySQL数据库的插入查询

我目前正在尝试学习使用Moq进行模拟,并且想在现有的数据库中进行尝试,但是我不确定如何正确地实现这一目标.

在我的数据层中,我有一个处理连接到DB的类,并具有用于插入,选择等的各种方法.我想测试一个actor是否已正确插入到数据库中.

我的插入方法当前如下所示：

public void Insert(string firstname, string lastname)
{
    string query = $"INSERT INTO `sakila`.`actor`(`first_name`,`last_name`) VALUES('" + firstname + "','" + lastname + "')";
    Console.WriteLine(query);
    //open connection
    if (this.OpenConnection() == true)
    {
        Console.WriteLine("Established connection");
        //create command and assign the query and connection from the constructor
        MySqlCommand cmd = new MySqlCommand(query, connection);

        //Execute command
        cmd.ExecuteNonQuery();
        Console.WriteLine("Insert query succesfully executed.");

        //close connection
        this.CloseConnection();
    }
}

我将如何使用Mocks做到这一点？我是否为演员实体创建一个类？我应该为我的DbConnection类创建一个接口吗？
对不起所有问题,但是我真的对如何解决这个问题感到困惑.

解决方法:

当前,被测方法过于紧密地与实现问题联系在一起,以致于无法轻松地对其进行单独的单元测试.尝试抽象出这些实现问题,以便可以轻松模拟它们以进行独立测试.

public interface IDbConnectionFactory {
    IDbConnection CreateConnection();
}

上面的连接工厂抽象可用于访问MySql数据存储的其他必要的System.Data抽象.

public class MyDataAccessClass {
    private IDbConnectionFactory connectionFactory;

    public MyDataAccessClass(IDbConnectionFactory connectionFactory) {
        this.connectionFactory = connectionFactory;
    }

    public void Insert(string firstname, string lastname) {
        var query = $"INSERT INTO `sakila`.`actor`(`first_name`,`last_name`) VALUES('" + firstname + "','" + lastname + "')";
        Console.WriteLine(query);
        using(var connection = connectionFactory.CreateConnection() {
            //Creates and returns a MySqlCommand object associated with the MySqlConnection. 
            using(var command = connection.CreateCommand()) {
                command.CommandText = query;
                Console.WriteLine("Established connection");
                connection.Open();
                command.ExecuteNonQuery();
                Console.WriteLine("Insert query succesfully executed.");
                connection.Close();//is not actually necessary as the using statement will make sure to close the connection.
            }
        }
    }
}

工厂的生产实现将返回实际的MySqlConnection

public class MySqlConnectionFactory: IDbConnectionFactory {
    public IDbConnection CreateConnection() {
        return new MySqlConnection("connection string");
    }
}

可以通过依赖注入将其传递到数据层

为了进行测试,您可以使用选择的模拟框架来模拟接口,或者创建自己的伪造品以注入和测试您的方法.

[TestClass]
public class DataAccessLayerUnitTest {
    [TestMethod]
    public void TestInsert() {
        //Arrange
        var commandMock = new Mock<IDbCommand>();
        commandMock
            .Setup(m => m.ExecuteNonQuery())
            .Verifiable();

        var connectionMock = new Mock<IDbConnection>();
        connectionMock
            .Setup(m => m.CreateCommand())
            .Returns(commandMock.Object);

        var connectionFactoryMock = new Mock<IDbConnectionFactory>();
        connectionFactoryMock
            .Setup(m => m.CreateConnection())
            .Returns(connectionMock.Object);

        var sut = new MyDataAccessClass(connectionFactoryMock.Object);
        var firstName = "John";
        var lastName = "Doe";

        //Act
        sut.Insert(firstName, lastName);

        //Assert
        commandMock.Verify();
    }
}

最后,建议您在命令文本中使用命令参数,因为构造查询字符串会手动打开代码以进行SQL注入攻击.

为了更好地了解如何使用Moq,请检查其Quickstart

标签：unit-testing,mocking,moq,c,mysql
来源： https://codeday.me/bug/20191111/2021037.html