Writing the rest of the tests

With all that said, let's write our second test and then hand it over to you to write the rest of them.

Testing that some data exists

The second test we need to write is the Get_ShouldReturnCustomer_WhenCustomerExists. For this test we need to create a customer as part of Arrange, try to retrieve them as part of Act and then validate that they are returned in the response in Assert. We also have to add the customer id in the list so it can get deleted.

Get_ShouldReturnCustomer_WhenCustomerExists

[Fact]
public async Task Get_ShouldReturnCustomer_WhenCustomerExists()
{
    // Arrange
    var request = new CustomerRequest
    {
        Email = "[email protected]",
        FullName = "Nick Chapsas",
        DateOfBirth = new DateTime(1993, 01, 01),
        GitHubUsername = "nickchapsas"
    };

    var createCustomerHttpResponse = await _client.PostAsJsonAsync("customers", request);
    var createdCustomer = await createCustomerHttpResponse.Content.ReadFromJsonAsync<CustomerResponse>();

    // Act
    var response = await _client.GetAsync($"customers/{createdCustomer!.Id}");

    // Assert
    response.StatusCode.Should().Be(HttpStatusCode.OK);
    var customerResponse = await response.Content.ReadFromJsonAsync<CustomerResponse>();

    customerResponse.Should().BeEquivalentTo(createdCustomer);
    
    // Cleanup
    _idsToDelete.Add(customerResponse!.Id);
}

Exercise: Write the following tests

The tests we need are:

• Create_ShouldReturnBadRequest_WhenTheEmailIsInvalid (The object used for bad requests is ValidationProblemDetails)
• GetAll_ShouldReturnAllCustomers_WhenCustomersExist (One customer is enough. The object used is GetAllCustomersResponse)
• Get_ShouldReturnNotFound_WhenCustomerDoesNotExist
• Update_ShouldUpdateCustomerDetails_WhenDetailsAreValid
• Delete_ShouldDeleteCustomer_WhenCustomerExists
• Delete_ShouldReturnNotFound_WhenCustomerDoesNotExist

Solutions

Only expand the solutions if you are stuck. You are highly encouraged to try and write the tests yourself. Practice makes perfect and you only learn by doing.

Create_ShouldReturnBadRequest_WhenTheEmailIsInvalid

[Fact]
public async Task Create_ShouldReturnBadRequest_WhenTheEmailIsInvalid()
{
    // Arrange
    var request = new CustomerRequest
    {
        Email = "nick",
        FullName = "Nick Chapsas",
        DateOfBirth = new DateTime(1993, 01, 01),
        GitHubUsername = "nickchapsas"
    };

    // Act
    var response = await _client.PostAsJsonAsync("customers", request);

    // Assert
    response.StatusCode.Should().Be(HttpStatusCode.BadRequest);

    var problemDetails = await response.Content.ReadFromJsonAsync<ValidationProblemDetails>();
    problemDetails!.Errors["Email"].Should().Equal("nick is not a valid email address");
}

GetAll_ShouldReturnAllCustomers_WhenCustomersExist

[Fact]
public async Task GetAll_ShouldReturnAllCustomers_WhenCustomersExist()
{
    // Arrange
    var request = new CustomerRequest
    {
        Email = "[email protected]",
        FullName = "Nick Chapsas",
        DateOfBirth = new DateTime(1993, 01, 01),
        GitHubUsername = "nickchapsas"
    };
    
    var createCustomerHttpResponse = await _client.PostAsJsonAsync("customers", request);
    var createdCustomer = await createCustomerHttpResponse.Content.ReadFromJsonAsync<CustomerResponse>();
    _idsToDelete.Add(createdCustomer!.Id);

    // Act
    var response = await _client.GetAsync("customers");

    // Assert
    var customerResponse = await response.Content.ReadFromJsonAsync<GetAllCustomersResponse>();
    response.StatusCode.Should().Be(HttpStatusCode.OK);
    customerResponse!.Customers.Should().ContainEquivalentOf(createdCustomer).And.HaveCount(1);
}

Get_ShouldReturnNotFound_WhenCustomerDoesNotExist

[Fact]
public async Task Get_ShouldReturnNotFound_WhenCustomerDoesNotExist()
{
    // Arrange
    var customerId = Guid.NewGuid();

    // Act
    var response = await _client.GetAsync($"customers/{customerId}");

    // Assert
    response.StatusCode.Should().Be(HttpStatusCode.NotFound);
}

Update_ShouldUpdateCustomerDetails_WhenDetailsAreValid

[Fact]
public async Task Update_ShouldUpdateCustomerDetails_WhenDetailsAreValid()
{
    // Arrange
    var createRequest = new CustomerRequest
    {
        Email = "[email protected]",
        FullName = "Nick Chapsas",
        DateOfBirth = new DateTime(1993, 01, 01),
        GitHubUsername = "nickchapsas"
    };
    
    var createCustomerHttpResponse = await _client.PostAsJsonAsync("customers", createRequest);
    var createdCustomer = await createCustomerHttpResponse.Content.ReadFromJsonAsync<CustomerResponse>();
    _idsToDelete.Add(createdCustomer!.Id);
    
    var updateRequest = new CustomerRequest
    {
        Email = "[email protected]",
        FullName = "Nick Chapsas",
        DateOfBirth = new DateTime(1993, 01, 01),
        GitHubUsername = "nickchapsas"
    };

    // Act
    var response = await _client.PutAsJsonAsync($"customers/{createdCustomer!.Id}", updateRequest);

    // Assert
    response.StatusCode.Should().Be(HttpStatusCode.OK);    
    var customerResponse = await response.Content.ReadFromJsonAsync<CustomerResponse>();
    customerResponse.Should().BeEquivalentTo(updateRequest);
}

Delete_ShouldDeleteCustomer_WhenCustomerExists

[Fact]
public async Task Delete_ShouldDeleteCustomer_WhenCustomerExists()
{
    // Arrange
    var createRequest = new CustomerRequest
    {
        Email = "[email protected]",
        FullName = "Nick Chapsas",
        DateOfBirth = new DateTime(1993, 01, 01),
        GitHubUsername = "nickchapsas"
    };
    
    var createCustomerHttpResponse = await _client.PostAsJsonAsync("customers", createRequest);
    var createdCustomer = await createCustomerHttpResponse.Content.ReadFromJsonAsync<CustomerResponse>();

    // Act
    var response = await _client.DeleteAsync($"customers/{createdCustomer!.Id}");

    // Assert
    response.StatusCode.Should().Be(HttpStatusCode.OK);
}

Delete_ShouldReturnNotFound_WhenCustomerDoesNotExist

[Fact]
public async Task Delete_ShouldReturnNotFound_WhenCustomerDoesNotExist()
{
    // Arrange
    var customerId = Guid.NewGuid();

    // Act
    var response = await _client.DeleteAsync($"customers/{customerId}");

    // Assert
    response.StatusCode.Should().Be(HttpStatusCode.NotFound);
}