Skip to main content

How to start Windows Azure emulator when running unit tests

Unit test need to be written even if we are working with on-premise services or with services from cloud. When working with Windows Azure, there are times when we want to write some integration test for Windows Azure tables, blobs or queues.
For these cases we don’t want to hit the Windows Azure from the cloud. This would increase or monthly subscription costs. Usually for this this Windows Storage emulator is used in combination with development storage account.
When we are on a development machine, where we already have Windows Azure Emulator stared we will not have any kind of problems. But will happen on a machine where Windows Azure Emulator is not started. All the tests will fail.
We can write a code in the class initialize step that star the emulator. In the end, the emulator is only a process that can be started from the command line.
The code that we would need to use will look something like this:
public class CloudStorageEmulatorShepherd
        public void Start()
                CloudStorageAccount storageAccount = CloudStorageAccount.DevelopmentStorageAccount;

                CloudBlobClient blobClient = storageAccount.CreateCloudBlobClient();
                CloudBlobContainer container = blobClient.GetContainerReference("test");
                            new BlobRequestOptions()
                                    RetryPolicy = RetryPolicies.NoRetry(),
                                    Timeout = new TimeSpan(0, 0, 0, 1)
            catch (TimeoutException)
                ProcessStartInfo processStartInfo = new ProcessStartInfo()
                    FileName = Path.Combine(
                                        @"C:\Program Files\Microsoft SDKs\Windows Azure\Emulator",
                    Arguments = @"/devstore",

                using (Process process = Process.Start(processStartInfo))
The path to the emulator can be different, based on Windows Azure version. This path can be extracted in the configuration file.  We are testing if the emulator is started by trying to creating a container.  It is very important to set the  NoRetry policty.
And in our unit test we would need something like this:
public static void ClassInit(TestContext context)
    CloudStorageEmulatorShepherd shepherd= new CloudStorageEmulatorShepherd();
In this way, we will be able to run integration test with Windows Azure without any kind of problem.


Popular posts from this blog

ADO.NET provider with invariant name 'System.Data.SqlClient' could not be loaded

Today blog post will be started with the following error when running DB tests on the CI machine:
threw exception: System.InvalidOperationException: The Entity Framework provider type 'System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer' registered in the application config file for the ADO.NET provider with invariant name 'System.Data.SqlClient' could not be loaded. Make sure that the assembly-qualified name is used and that the assembly is available to the running application. See for more information. at System.Data.Entity.Infrastructure.DependencyResolution.ProviderServicesFactory.GetInstance(String providerTypeName, String providerInvariantName) This error happened only on the Continuous Integration machine. On the devs machines, everything has fine. The classic problem – on my machine it’s working. The CI has the following configuration:

TeamCity.NET 4.51EF 6.0.2VS2013
It seems that there …

GET call of REST API that contains '/'-slash character in the value of a parameter

Let’s assume that we have the following scenario: I have a public HTTP endpoint and I need to post some content using GET command. One of the parameters contains special characters like “\” and “/”. If the endpoint is an ApiController than you may have problems if you encode the parameter using the http encoder.
using (var httpClient = new HttpClient()) { httpClient.BaseAddress = baseUrl; Task<HttpResponseMessage> response = httpClient.GetAsync(string.Format("api/foo/{0}", "qwert/qwerqwer"))); response.Wait(); response.Result.EnsureSuccessStatusCode(); } One possible solution would be to encode the query parameter using UrlTokenEncode method of HttpServerUtility class and GetBytes method ofUTF8. In this way you would get the array of bytes of the parameter and encode them as a url token.
The following code show to you how you could write the encode and decode methods.

Entity Framework (EF) TransactionScope vs Database.BeginTransaction

In today blog post we will talk a little about a new feature that is available on EF6+ related to Transactions.
Until now, when we had to use transaction we used ‘TransactionScope’. It works great and I would say that is something that is now in our blood.
using (var scope = new TransactionScope(TransactionScopeOption.Required)) { using (SqlConnection conn = new SqlConnection("...")) { conn.Open(); SqlCommand sqlCommand = new SqlCommand(); sqlCommand.Connection = conn; sqlCommand.CommandText = ... sqlCommand.ExecuteNonQuery(); ... } scope.Complete(); } Starting with EF6.0 we have a new way to work with transactions. The new approach is based on Database.BeginTransaction(), Database.Rollback(), Database.Commit(). Yes, no more TransactionScope.
In the followi…