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Add custom properties to telemetry request at controller level

I am trying to add specific properties to telemetry request for every route.
After digging a bit, I've found that I can create my own custom TelemetryInitializer by implementing ITelemetryInitializer.
By doing this I've managed to add global properties to the request.
However, I still need to add specific properties at the controller level.
Do you have any idea how can I achieve this?
I've tried to inject TelemetryClient into the controller, but if I use it the properties are shared between requests.
This is how I've tried to log in the controller:
private TelemetryClient telemetryClient;
public ValueController(TelemetryClient telemetryClient)
{
this.telemetryClient = telemetryClient;
}
[HttpGet]
public async Task<IActionResult> RouteOne([FromQuery(Name = "param1")]string param1, [FromQuery(Name = "param2")]string param2)
{
telemetryClient.Context.GlobalProperties["param1"] = param1;
telemetryClient.Context.GlobalProperties["param2"] = param2;
}
[HttpGet]
public async Task<IActionResult> RouteTwo([FromQuery(Name = "param3")]string param3, [FromQuery(Name = "param4")]string param4)
{
telemetryClient.Context.GlobalProperties["param3"] = param3;
telemetryClient.Context.GlobalProperties["param4"] = param4;
}
And this is the implementation of ITelemetryInitializer:
public class CustomPropertiesTelemetryInitializer : ITelemetryInitializer
{
private readonly IHttpContextAccessor httpContextAccessor;
public CustomPropertiesTelemetryInitializer(IHttpContextAccessor httpContextAccessor)
{
this.httpContextAccessor = httpContextAccessor;
}
public void Initialize(ITelemetry telemetry)
{
telemetry.Context.GlobalProperties["RequestId"] = httpContextAccessor.HttpContext.GetProperty("requestId");
telemetry.Context.GlobalProperties["Ip"] = httpContextAccessor.HttpContext?.Connection.RemoteIpAddress.ToString();
telemetry.Context.GlobalProperties["RoutePath"] = httpContextAccessor.HttpContext?.Request.Path;
}
}

If the properties you added are always like "paramxxx", then there is a workaround(but it's really not very elegant).
In the controller constructor, check the GlobalProperties if it contains key like "paramxxx":
public ValueController(TelemetryClient telemetryClient)
{
this.telemetryClient = telemetryClient;
var props = this.telemetryClient.Context.GlobalProperties;
foreach (var p in props)
{
if (p.Key.Contains("param"))
{
props.Remove(p.Key);
}
}
}

The key here is to use the DI framework. You can use it to get request-scoped data or services into your ITelemetryInitializer.
(These examples are based on the standard ASP.Net Dependency Injection framework. This pattern should work with any DI framework, but will need to be adjusted slightly.)
First, create a class to represent your request-scoped telemetry. I've used a simple DTO, but this could also be a service that knows how to fetch/generate the data itself. Register it using AddScoped. "Scoped" means that a new instance will be created for each HTTP request, and then that instance will be re-used within that request.
Because I used a DTO, I didn't bother with an interface--you should use an interface if the class contains any logic you'll want to mock in unit tests.
public class RequestScopedTelemetry
{
public string MyCustomProperty { get; set; }
}
services.AddScoped<RequestScopedTelemetry>();
Now, create the ITelemetryInitializer and register it as a singleton. App Insights will discover and use it through the DI framework.
class RequestScopedTelemetryInitializer : ITelemetryInitializer
{
readonly IHttpContextAccessor httpContextAccessor;
public RequestScopedTelemetryInitializer(IHttpContextAccessor httpContextAccessor)
=> this.httpContextAccessor = httpContextAccessor;
public void Initialize(ITelemetry telemetry)
{
// Attempt to resolve the request-scoped telemetry from the DI container
var requestScopedTelemetry = httpContextAccessor
.HttpContext?
.RequestServices?
.GetService<RequestScopedTelemetry>();
// RequestScopedTelemetry is only available within an active request scope
// If no telemetry available, just move along...
if (requestScopedTelemetry == null)
return;
// If telemetry was available, add it to the App Insights telemetry collection
telemetry.Context.GlobalProperties[nameof(RequestScopedTelemetry.MyCustomProperty)]
= requestScopedTelemetry.MyCustomProperty;
}
}
services.AddSingleton<ITelemetryInitializer, RequestScopedTelemetryInitializer>();
Finally, in your controller method, set your per-request values. This part isn't necessary if your telemetry class is able to fetch or generate the data itself.
public class ExampleController : ControllerBase
{
readonly RequestScopedTelemetry telemetry;
public ValuesController(RequestScopedTelemetry telemetry)
=> this.telemetry = telemetry;
[HttpGet]
public ActionResult Get()
{
telemetry.MyCustomProperty = "MyCustomValue";
// Do what you want to
return Ok();
}
}

In order to add per request data into telemetry, you need to have a way to share data within the request. A reliable way is by using HttpContent.Items property, which is basically a Dictionary.
You can create a service to keep a Dictionary inside HttpContent.Items with all custom data you want in telemetry (key prefix is used to ensure we only read the things we want later in Initializer):
public class LogTelemetryRequest
{
private const string KEY_PREFIX = "CustomTelemetryData_";
private readonly IHttpContextAccessor _httpContextAccessor;
public LogTelemetryRequest(IHttpContextAccessor httpContextAccessor)
{
_httpContextAccessor = httpContextAccessor;
}
public void AddProperty(string key, string value)
{
_httpContextAccessor.HttpContext.Items[KEY_PREFIX + key] = value;
}
}
Register this as scoped in Startup.cs:
services.AddScoped<LogTelemetryRequest>();
Use it in your controller:
private LogTelemetryRequest logTelemetryRequest;
public ValueController(LogTelemetryRequest logTelemetryRequest)
{
this.logTelemetryRequest = logTelemetryRequest;
}
[HttpGet]
public async Task<IActionResult> RouteOne([FromQuery(Name = "param1")]string param1, [FromQuery(Name = "param2")]string param2)
{
// telemetryClient.Context.GlobalProperties["param1"] = param1;
// telemetryClient.Context.GlobalProperties["param2"] = param2;
logTelemetryRequest.AddProperty("param1", param1);
logTelemetryRequest.AddProperty("param2", param2);
}
Then read it within initializer:
public class AddCustomTelemetryInitializer : ITelemetryInitializer
{
private const string KEY_PREFIX = "CustomTelemetryData_";
private readonly IHttpContextAccessor _httpContextAccessor;
public AddCustomTelemetryInitializer(IHttpContextAccessor httpContextAccessor)
{
_httpContextAccessor = httpContextAccessor;
}
public void Initialize(ITelemetry telemetry)
{
var requestTelemetry = telemetry as RequestTelemetry;
if (requestTelemetry == null) return;
foreach (var item in _httpContextAccessor.HttpContext.Items)
{
if (item.Key is string key && key.StartsWith(KEY_PREFIX))
requestTelemetry.Properties.Add(key, item.Value.ToString());
}
}
}
Ideally LogTelemetryRequest should be registered using an interface, and the key prefix should be a single shared constant, didn't do for the sake of simplicity.

How to dynamically change change DI using autofac?

We are developing windows service, and i want to change dbcontext class dynamically in repositories.
bellow is the scenario.
I have three db context classes
public abstract class Context : DbContext, IUnitOfWork
{
protected Context(string connectionString) : base(connectionString)
{
}
}
public class PlatformContext : Context
{
private readonly string _connectionString;
public PlatformContext(string connectionString)
: base(connectionString)
{
_connectionString = connectionString;
}
}
public class PlatformReplicaContext : Context
{
private readonly string _connectionString;
public PlatformReplicaContext(string connectionString)
: base(connectionString)
{
_connectionString = connectionString;
}
}
public class TempContext : Context
{
private readonly string _connectionString;
public TempContext(string connectionString)
: base(connectionString)
{
_connectionString = connectionString;
}
}
and i have repository
public interface ICategoryRepository : IRepository<Category>
{
}
public class CategoryRepository :Repository<Category>, ICategoryRepository
{
public CategoryRepository(Context context) : base(context)
{
}
}
hence im using CQRS i have another three classes
public class CategoryBasicQuery:IRequest<BaseQueryResponse>
{
public int CategoryId { get; set; }
}
public class CategoryBasicQueryHandler : IRequestHandler<CategoryBasicQuery, BaseQueryResponse>
{
private readonly ICategoryRepository _categoryRepository;
private readonly IMapper _mapper;
public CategoryBasicQueryHandler(ICategoryRepository categoryRepository, IMapper mapper)
{
_categoryRepository = categoryRepository;
_mapper = mapper;
}
public async Task<BaseQueryResponse> Handle(CategoryBasicQuery request, CancellationToken cancellationToken)
{
var entry = await _categoryRepository.FindAsync(request.CategoryId);
if (entry == null)
{
return new NotFoundResponse();
}
var response = _mapper.Map<CategoryBasicResponse>(entry);
return response;
}
}
Now here is the issue
Here category repository should be able to execute queries in all 3 types of contexts.
but how should i register classes in using autofac?
then i came up with a solution generating repositories in run time as below
public class RepositoryFactory
{
public static TRepository GetRepositoryInstance<T, TRepository>(
params object[] args)
where TRepository : IRepository<T>
{
return (TRepository)Activator.CreateInstance(typeof(TRepository), args);
}
}
im calling this method inside CategoryBasicQueryHandler class like this
var categoryRepo = RepositoryFactory.GetRepositoryInstance<Category, CategoryRepository>(new PlatformReplicaContext("connectionString"));
but when calling from CQRS
var categoty = new Category();
var command = new CategoryBasicQuery {CategoryId = categoryId};
var result = _mediator.Send(command);
VS give me following error
and my autofac registration as follows
builder.RegisterType<CategoryService>().AsSelf();
builder.RegisterType<ActionRepository>().As<IActionRepository>();
builder.RegisterType<CategoryRepository>().As<ICategoryRepository>();
builder.RegisterType<Mapper>().As<IMapper>();
can anyone help me resolve this or suggest good method to handle this situation.
thanks.

This may give you a good starting point for a possible solution: http://autofaccn.readthedocs.io/en/latest/resolve/relationships.html#keyed-service-lookup-iindex-x-b
builder.RegisterType<PlatformContext>().Keyed<Context>("platform");
builder.RegisterType<PlatformReplicaContext>().Keyed<Context>("replica");
builder.RegisterType<TempContext>().Keyed<Context>("temp");
You mentioned in a comment that there is a variable named action somewhere that will indicate which implementation to use:
public class Class1
{
private readonly IIndex<string, Context> contexts;
public Class1(IIndex<string, Context> contexts)
{
this.contexts = contexts;
}
public void Whatever()
{
string action = ...; // platform, replica or temp
Context context = this.contexts[action];
...
}
}
Of course this needs to be adapted so that it will fit in the rest of your application design. A possible example could be:
Context context = this.contexts[action];
using(ILifetimeScope scope = container.BeginLifetimeScope(builder =>
{
builder.RegisterInstance(context).As<Context>();
}))
{
// Because we are resolving IMediator from the scope, the selected Context will be used in all dependencies
var mediator = scope.Resolve<IMediator>();
mediator.Send(...);
}

Unit test RabbitMQ push with C# - .Net Core

I have created a .net core API, which pushes a message in RabbitMQ queue. I have used IOptions to read configuration data from .json file and added it as dependency.
Below is the code of my controller:
[Route("api/[controller]")]
public class RestController : Controller
{
private RabbitMQConnectionDetail _connectionDetail;
public RestController(IOptions<RabbitMQConnectionDetail> connectionDetail)
{
_connectionDetail = connectionDetail.Value;
}
[HttpPost]
public IActionResult Push([FromBody] OrderItem orderItem)
{
try
{
using (var rabbitMQConnection = new RabbitMQConnection(_connectionDetail.HostName,
_connectionDetail.UserName, _connectionDetail.Password))
{
using (var connection = rabbitMQConnection.CreateConnection())
{
var model = connection.CreateModel();
var helper = new RabbitMQHelper(model, "Topic_Exchange");
helper.PushMessageIntoQueue(orderItem.Serialize(), "Order_Queue");
}
}
}
catch (Exception)
{
return StatusCode((int)HttpStatusCode.BadRequest);
}
return Ok();
}
}
Connection details class has the below properties
public class RabbitMQConnectionDetail
{
public string HostName { get; set; }
public string UserName { get; set; }
public string Password { get; set; }
}
Now I want to unit test it, but since I am going to test it against a blackbox, I'm not able to think of how to unit test it and looking for kind help.
ConnectionClass
public class RabbitMQConnection : IDisposable
{
private static IConnection _connection;
private readonly string _hostName;
private readonly string _userName;
private readonly string _password;
public RabbitMQConnection(string hostName, string userName, string password)
{
_hostName = hostName;
_userName = userName;
_password = password;
}
public IConnection CreateConnection()
{
var _factory = new ConnectionFactory
{
HostName = _hostName,
UserName = _userName,
Password = _password
};
_connection = _factory.CreateConnection();
var model = _connection.CreateModel();
return _connection;
}
public void Close()
{
_connection.Close();
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
protected virtual void Dispose(bool disposing)
{
if (disposing)
{
_connection.Close();
}
}
~ RabbitMQConnection()
{
Dispose(false);
}
}
Helper class
public class RabbitMQHelper
{
private static IModel _model;
private static string _exchangeName;
const string RoutingKey = "dummy-key.";
public RabbitMQHelper(IModel model, string exchangeName)
{
_model = model;
_exchangeName = exchangeName;
}
public void SetupQueue(string queueName)
{
_model.ExchangeDeclare(_exchangeName, ExchangeType.Topic);
_model.QueueDeclare(queueName, true, false, false, null);
_model.QueueBind(queueName, _exchangeName, RoutingKey);
}
public void PushMessageIntoQueue(byte[] message, string queue)
{
SetupQueue(queue);
_model.BasicPublish(_exchangeName, RoutingKey, null, message);
}
public byte[] ReadMessageFromQueue(string queueName)
{
SetupQueue(queueName);
byte[] message;
var data = _model.BasicGet(queueName, false);
message = data.Body;
_model.BasicAck(data.DeliveryTag, false);
return message;
}
}

Tightly coupling your Controller to implementation concerns are making it difficult to test your controller without side-effects. From the sample you provided you have shown that you are encapsulating the 3rd part API implementations and only exposing abstractions. Good. You however have not created an abstraction that would allow you to mock them when testing. I suggest a refactor of the RabbitMQConnection to allow for this.
First have your own backing abstraction.
public interface IRabbitMQConnectionFactory {
IConnection CreateConnection();
}
And refactor RabbitMQConnection as follows
public class RabbitMQConnection : IRabbitMQConnectionFactory {
private readonly RabbitMQConnectionDetail connectionDetails;
public RabbitMQConnection(IOptions<RabbitMQConnectionDetail> connectionDetails) {
this.connectionDetails = connectionDetails.Value;
}
public IConnection CreateConnection() {
var factory = new ConnectionFactory {
HostName = connectionDetails.HostName,
UserName = connectionDetails.UserName,
Password = connectionDetails.Password
};
var connection = factory.CreateConnection();
return connection;
}
}
Take some time and review exactly what was done with this refactor. The IOptions was moved from the Controller to the factory and the RabbitMQConnection has also been simplified to do it's intended purpose. Creating a connection.
The Controller now would need to be refactored as well
[Route("api/[controller]")]
public class RestController : Controller {
private readonly IRabbitMQConnectionFactory factory;
public RestController(IRabbitMQConnectionFactory factory) {
this.factory = factory;
}
[HttpPost]
public IActionResult Push([FromBody] OrderItem orderItem) {
try {
using (var connection = factory.CreateConnection()) {
var model = connection.CreateModel();
var helper = new RabbitMQHelper(model, "Topic_Exchange");
helper.PushMessageIntoQueue(orderItem.Serialize(), "Order_Queue");
return Ok();
}
} catch (Exception) {
//TODO: Log error message
return StatusCode((int)HttpStatusCode.BadRequest);
}
}
}
Again note the simplification of the controller. This now allows the factory to be mocked and injected when testing and by extension allows the mocks to be used by the RabbitMQHelper. You can use your mocking framework of choice for dependencies or pure DI.

I dont think it is a unit test scenario. If you want to to test with external component ie database or message queue then i suggest you do it as integration test.
What we do is to have a sand box environment with component SQL database and azure message bus. We have code to correctly set the state for this component ie seed the database and clear the message bus. Then we run test on the environment and check the state of the database or message bus count etc.

Dependency injection implementation for app setting c#

NotificationHubConnectionSettings.cs file to fetch connection string from web.config
public class NotificationHubConnectionSettings
{
public NotificationHubClient Hub { get; set; }
public NotificationHubConnectionSettings()
{
Hub = NotificationHubClient.CreateClientFromConnectionString(ConfigurationManager.AppSettings["Microsoft.Azure.NotificationHubs.ConnectionString"], ConfigurationManager.AppSettings["NotificationHub"]);
}
}
Inside Bootstrapper.cs
using Unity dependency injection nuget
private static IUnityContainer BuildUnityContainer()
{
try
{
var container = new UnityContainer();
container.RegisterType<NotificationHubConnectionSettings>().RegisterType<NotificationHubConnectionSettings>(new HierarchicalLifetimeManager());
return container;
}
catch (Exception)
{
return null;
}
}
In HomeController.cs
want to implement dependency injection -
private readonly NotificationHubClient _hub;
public HomeController(NotificationHubConnectionSettings hub)
{
_hub = hub.Hub;
}
// POST api/register
// This creates a registration id
public async Task<string> Post(string handle = null)
{
string newRegistrationId = null;
if (handle != null)
{
var registrations = await _hub.GetRegistrationsByChannelAsync(handle, 100);
Is this correct way to implement dependency injection?

You should be using a interface type here.
Create a contract for INotificationHubConnectionSettings class in the form of a interface which dictates to your system all public methods and properties available.
public interface INotificationHubConnectionSettings
{
NotificationHubClient Hub { get; set; }
}
Then have your actual NotificationHubConnectionSettings class inherit from this interface;
public class NotificationHubConnectionSettings : INotificationHubConnectionSettings
{
public NotificationHubClient Hub { get; set; }
public NotificationHubConnectionSettings()
{
Hub = NotificationHubClient.CreateClientFromConnectionString(ConfigurationManager.AppSettings["Microsoft.Azure.NotificationHubs.ConnectionString"], ConfigurationManager.AppSettings["NotificationHub"]);
}
}
Now register the interface and class inside of UnityContainer and change your constructor to the following;
private readonly INotificationHubClient _hub;
public HomeController(NotificationHubConnectionSettings hub)
{
_hub = hub.Hub;
}
Always use interfaces for dependency injection.

ServiceStack testing methods that works with EF

As an answer to my own question:
What would be the most elegant way to use Entity Framework with Generic Repository, in Service Stack, and to write Integration \ Unit Tests for service?
At the moment, this is how my structure looks like:
Generic repository layer:
public class GenericRepository<TEntity> where TEntity : class
{
internal DbContext Context;
//...
//CRUD Operations, etc.
}
Unit of work layer:
public class UnitOfWork : IDisposable
{
private readonly DbContext _context;
public UnitOfWork(DbContext ctx)
{
_context = ctx;
}
private bool _disposed;
private GenericRepository<User> _userRepository;
public GenericRepository<User> UserRepository
{
get { return _userRepository ?? (_userRepository = new GenericRepository<User>(_context)); }
}
//...
}
Business layer:
public class UserBusiness
{
public UnitOfWork UoW { get; set; }
public void AddUser(Models.User user)
{
//Map from domain model to entity model
var u = Mapper.Map<Models.User, DAL.Repository.User>(user);
UoW.UserRepository.Insert(u);
UoW.Save();
}
}
API project:
public class AppHost : AppHostBase
{
public AppHost() : base("Users Service", typeof(UsersService).Assembly) { }
//...
public override void Configure(Funq.Container container)
{
//...other configuration
//UoW registration
container.Register(c => new UnitOfWork(new DbContext("my-DB-connection"))).ReusedWithin(Funq.ReuseScope.Hierarchy);
//Business layer class registration
container.Register<UserBusiness>(c=>new UserBusiness {
UoW = c.Resolve<UnitOfWork>()
}).ReuseWithin(Funq.ReuseScope.Hierarchy);
}
}
public class UsersService : Service
{
public UserBusiness UB { get; set; }
public object Post(User u)
{
UB.AddUser(u);
//...
}
}
So when it comes to integration testing, I can just do something like this:
Declare _appHost
private ServiceStackHost _appHost;
And configure funq container like this:
public override void Configure(Funq.Container container)
{
//...create mocked context
var mockedContext = new Mock<IDbContext>();
mockedContext.Setup(x => x.Set<User>()).Returns(new List<User>
{
new User { ID = 1, FirstName = "John", LastName = "Doe" }
});
//(or use effort or any other way to create it)
container.Register(c => new UnitOfWork(mockedContext)).ReusedWithin(Funq.ReuseScope.Hierarchy);
}
And test as usual:
[Test]
public void Get_User_By_Id()
{
//...generate client instance (JsonServiceClient) etc.
var customer = client.Get(new GetCustomer { Id = 1 });
Assert.AreEqual("John", customer.FirstName);
///...
}
In addition to have all layers available for DI, and mocking, I also created IDbContext, IGenericRepository, IUnitOfWork, etc. interfaces.
I didn't include it here in order to keep this as simple as I could.
But I would like to hear if there's a better (more elegant way) to do it.