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Why doesn't the IOptions pattern work in my Azure function?

I don't understand why the IOptions pattern doesn't work in an Azure function type of project. The values are just not loaded in the variables.
This is my Startup.cs code:
public class Startup : FunctionsStartup
{
public override void Configure(IFunctionsHostBuilder builder)
{
builder.Services.AddOptions<ExpOptions>()
.Configure<IConfiguration>((settings, configuration) =>
{
configuration.GetSection("ExpOptions").Bind(settings);
});
}
}
Here is my function class:
public class Sum2
{
private readonly IConfiguration _configuration;
private readonly ExpOptions _settings;
public Sum2(IConfiguration configuration, IOptions<ExpOptions> options)
{
_configuration = configuration;
_settings = options.Value;
}
[FunctionName("Sum2")]
public async Task<IActionResult> Run(
[HttpTrigger(AuthorizationLevel.Function, "get", "post", Route = null)] HttpRequest req,
ILogger log)
{
// ExpOptions options = _configuration.GetSection("ExpOptions").Get<ExpOptions>(); // this line would work but it's not loading the settings through IOptions pattern
var message = $"{JsonConvert.SerializeObject(_settings)}";
log.LogInformation(message);
return new OkObjectResult(message);
}
}
Here is the options class:
public class ExpOptions
{
public string ConnStr { get; set; }
public string BaseAddress { get; set; }
public string UserName { get; set; }
public string Password { get; set; }
}
And finally in the Azure function, in the Configurations tab, I have the values added like so:
ExpOptions:ConnString
ExpOptions:BaseAddress
ExpOptions:UserName
ExpOptions:Password

Global model in controller ASP.NET Core MVC 6

I have Home / Index where show list of Current Tasks, Completed Tasks and form for creating new task.
I created HomeIndexViewModel for pass models (Completed tasks, Current Tasks and TaskCreateViewModel for form) to Index View and there call (#Model.CompletedTasks, #Model.CurrentTasks and #Model.FormCreate)
But in CreatedTaskViewModel I want to get information about validation errors and render them in View. I init in Controller HomeIndexViewModel and get access from Index(Action) and Create(Action).
Approach worked, but I am not sure what it's good idea.
public class HomeIndexViewModel
{
public List<TaskModel> CompletedTasks { get; set; } = new List<TaskModel>();
public List<TaskModel> CurrentTasks { get; set; } = new List<TaskModel>();
public CreateTaskViewModel FormCreate { get; set; } = new CreateTaskViewModel();
}
public class HomeController : Controller
{
private readonly ITaskRepository _taskRepository;
private HomeIndexViewModel homeIndexViewModel;
public HomeController(IConfiguration configuration)
{
_taskRepository = new TaskRepository(configuration.GetConnectionString("AppDB"));
homeIndexViewModel = new HomeIndexViewModel()
{
CompletedTasks = _taskRepository.GetList("completed");
CurrentTasks = _taskRepository.GetList("current");
};
public ActionResult Index()
{
return View(homeIndexViewModel);
}
public ActionResult Create(CreateTaskViewModel task)
{
if (ModelState.IsValid)
{
_taskRepository.Create(task);
}
return View(nameof(Index), homeIndexViewModel);
}

I think you could write a service and inject it to your controller:
public interface ISomeService
{
public HomeIndexViewModel GetHomeIndexViewModel(IConfiguration configuration, ITaskRepository taskRepository)
{
//some codes
HomeIndexViewModel homeIndexView = new HomeIndexViewModel()
{
//some codes
};
return homeIndexView;
}
}
public class SomeService : ISomeService
{
public HomeIndexViewModel GetHomeIndexViewModel(IConfiguration configuration, ITaskRepository taskRepository)
{
//some codes
HomeIndexViewModel homeIndexView = new HomeIndexViewModel()
{
//some codes
};
return homeIndexView;
}
}
In your Startup Class：
public void ConfigureServices(IServiceCollection services)
{
.....
services.AddTransient<ISomeService, SomeService>();
.....
}
In your Controller：
public class HomeController : Controller
{
private readonly ILogger<HomeController> _logger;
private readonly ISomeService _someService;
private readonly ITaskRepository _taskRepository;
private readonly IConfiguration _configuration;
public HomeController(ILogger<HomeController> logger, ISomeService someService, ITaskRepository taskRepository, IConfiguration configuration)
{
_logger = logger;
_someService = someService;
_taskRepository = taskRepository;
_configuration = configuration;
}
public IActionResult Index()
{
var homeindexviewmodel = _someService.GetHomeIndexViewModel(_configuration,_taskRepository);
//you could get the homeindexviewmodel in other controllers with the same method
return View();
}
}

Using DBContext in repository class

I want to use my DBcontext in my repository class, but I don't know how at the moment. I've tried looking at other questions, but they don't provide the answer needed specific for my case.
I'll start with my controller:
public class MovieController : ControllerBase
{
IMovieService _movieService;
public MovieController(IMovieService movieService)
{
_movieService = movieService;
}
Service class:
public interface IMovieService
{
Movie RetrieveMovie(long id);
IEnumerable<Movie> RetrieveMovies();
}
public class MovieService : IMovieService
{
IMovieRepository _movieRepository;
public MovieService(IMovieRepository movieRepository)
{
_movieRepository = movieRepository;
}
Repository class:
public interface IMovieRepository
{
Movie GetMovieById(long id);
IEnumerable<Movie> GetMovies();
}
public class MovieRepository : IMovieRepository
{
private readonly MusicContext _db;
public Movie GetMovieById(long id)
{
return _db.Movie.Find(id);
}
DBContext:
public class MovieContext : DbContext
{
public MovieContext(DbContextOptions<MovieContext> options)
: base(options)
{
}
public DbSet<Movie> Movies { get; set; }
}
And last my startup function:
public void ConfigureServices(IServiceCollection services)
{
services.AddDbContext<MovieContext>(options =>
options.UseSqlServer(Configuration.GetConnectionString("MovieContext")));
services.AddControllers();
services.AddSwaggerGen(c =>
{
c.SwaggerDoc("v1", new OpenApiInfo { Title = "Movie.Api", Version = "v1" });
});
}
At the moment Visual studio warns me # MusicContext _db that this field is never assigned to, which I get. How can I get this to work?

you have to add a constructor to a MovieRepository and use DI
public class MovieRepository : IMovieRepository
{
private readonly MovieContext _db;
public MovieRepository (MovieContext db)
{
_db=db;
}
public Movie GetMovieById(long id)
{
return _db.Movie.Find(id);
}
.....
}

Inject different implementations that have same interface in multiple constructor parameters

My goal is to create an object that contains different implementations of an interface and at runtime select the implementation to use. I'm using the Dependency injection in ASP.NET Core.
Code:
public interface IStateRepository : IDbReadRepository<IState> { }
public interface IDbReadRepository<T> : IBaseRepository
{
IReadOnlyList<T> GetAll();
}
public interface IBaseRepository
{
IUserContext UserContext { get; set; }
}
namespace MvcOpinionatedTemplate.Repositories.Dapper
{
public class StateRepository : BaseDbRepository, IStateRepository
{
public StateRepository(IUserContext userContext, IDbConnection dbConnection) : base(userContext, dbConnection) { }
public IReadOnlyList<IState> GetAll()
{
return _dbConnection.Query<State>("SELECT * FROM State").ToList();
}
}
}
namespace Template.Repositories.Local
{
public class StateRepository : BaseRepository, IStateRepository
{
public StateRepository(IUserContext userContext) : base(userContext) { }
public IReadOnlyList<IState> GetAll()
{
var filePath = Path.Combine(AppContext.BaseDirectory, #"Local\json\states.json");
return JsonConvert.DeserializeObject<List<State>>(File.ReadAllText(filePath));
}
}
namespace MvcOpinionatedTemplate.Repositories.Collections
{
public class StateRepositories
{
public IStateRepository Local { get; }
public IStateRepository SqlServer { get; }
public StateRepositories(IStateRepository local, IStateRepository sqlServer)
{
Local = local;
SqlServer = sqlServer;
}
}
}
What I'd like to do is set in the Startup.ConfigureServices():
services.AddTransient<StateRepositories, XXXXX>
I tried this:
services.AddTransient<StateRepositories>(s => new StateRepositories(new Repositories.Local.StateRepository(--UserContext--), new Repositories.Dapper.StateRepository(-UserContext--)));
The problem is how to have DI populate UserContext. I have it defined Startup.ConfigureServices():
services.AddScoped<IUserContext, UserContext>();
How do have DI populate UserContext for the StateRepositories implementations? Or is there a better approach to achieve my goal?

You can register your IStateRepository separately and then inject IEnumerable<IStateRepository> which injects all implementations of IStateRepository.
public interface IStateRepository
{
}
public class LocalRepository : IStateRepository
{
}
public class DapperRepository : IStateRepository
{
}
services.AddTransient<IStateRepository, LocalRepository>()
.AddTransient<IStateRepository, DapperRepository>()
.AddTransient<StateRepositories>();
public class StateRepositories
{
public IStateRepository Local { get; }
public IStateRepository SqlServer { get; }
public StateRepositories(IEnumerable<IStateRepository> repositories)
{
Local = repositories.OfType<LocalRepository>().FirstOrDefault();
SqlServer = repositories.OfType<DapperRepository>().FirstOrDefault();
}
}

How to inject a parameter constructor into Repository constructor using Ninject?

I am trying to create DBContect object by passing connection string at run time.
Following is the structure of my NiNject Repository implementation.
public class HomeController : ApiController
{
MyService _service{ get; set; }
public HomeController(MyService service)
{
_service= service;
}
}
public class MyService
{
IRepository _repo { get; set; }
public MyService(IRepository repo)
{
_repo = repo;
}
}
Repository implementation is as follows :
public interface IRepository
{
TenantDbContext _db { get; set; }
void Add<T>(T entity) where T : class;
void Delete<T>(int id) where T : class;
T Find<T>(int id) where T : class;
IQueryable<T> Query<T>() where T : class;
void SaveChanges();
MasterDbContext _db_master { get; set; }
void Add_Master<T>(T entity) where T : class;
void Delete_Master<T>(int id) where T : class;
T Find_Master<T>(int id) where T : class;
IQueryable<T> Query_Master<T>() where T : class;
void SaveChanges_Master();
}
public class Repository : IRepository
{
public TenantDbContext _db { get; set; }
public MasterDbContext _db_master { get; set; }
public Repository(TenantDbContext db)
{
_db = db;
}
public Repository(MasterDbContext db_master)
{
_db_master = db_master;
}
public IQueryable<T> Query<T>() where T : class
{
return _db.Set<T>().AsQueryable();
}
public IQueryable<T> Query_Master<T>() where T : class
{
return _db_master.Set<T>().AsQueryable();
}
//.....Rest of the implemetation
}
Here goes my TenantDBContext class which takes an argument as a database string. No default constructor
public class TenantDbContext : DbContext
{
public TenantDbContext(string connString)
: base(connString)
{
//Configuration.AutoDetectChangesEnabled = true;
//Configuration.LazyLoadingEnabled = false;
//Configuration.ProxyCreationEnabled = false; //change tracking
}
public static TenantDbContext Create(string DbString)
{
// Some logic to get the tenant database string.
// Presently i am just passing it hard coded as follows.
return new TenantDbContext(DbString);
}
}
public class MasterDbContext : IdentityDbContext<ApplicationUser>
{
public MasterDbContext() : base("MasterDBConnection", throwIfV1Schema: false)
{
// dbmigration.AutomaticMigrationsEnabled = true;
Configuration.ProxyCreationEnabled = false;
Configuration.LazyLoadingEnabled = false;
}
public static MasterDbContext Create()
{
return new MasterDbContext();
}
//public DbSet<ApplicationUser> ApplicationUsers { get; set; }
public DbSet<Tenant> Tenants { get; set; }
public DbSet<TenantUserMap> TenantUserMaps { get; set; } }
Finally, RegisterServices which i have in my NinjectWebCommons.cs looks as follows :
Each Tenant have its different database. We are fetching out the Tenant name from the access token on every request and caching that requested Tenant object so we can pass the correct Tenant Database string in order to do the operations on the requested Tenant Database.
Below snippet, We are fetching the Tenant object from the current request cache which will provide us the Tenant Database string of the requested client.
public Tenant Tenant
{
get
{
object multiTenant;
if (!HttpContext.Current.GetOwinContext().Environment.TryGetValue("MultiTenant", out multiTenant))
{
throw new ApplicationException("Could Not Find Tenant");
}
return (Tenant)multiTenant;
}
}
private static void RegisterServices(IKernel kernel)
{
kernel.Bind<IRepository>().To<Repository>();
kernel.Bind<TenantDbContext>().ToMethod(_ =>
TenantDbContext.Create(Tenant.DBString));
kernel.Bind<MasterDbContext>().ToMethod(__ => MasterDbContext.Create());
}
Problem : When i add second binding in my NinjectWebCommons.cs "kernel.Bind()" , i start getting exception saying that "No default constructor found". It is simply not taking two bindings with the kernal. Request you to please have a look at the code above and point me out where i am going wrong.
I will appreciate your help. Thanks in Advance.

You may add a binding for the database context and point Ninject to use your factory method:
kernel.Bind<TenantDbContext>().ToMethod(_ => TenantDbContext.Create());