Do I need to Dispose dbconext EF 3.1? - entity-framework

Do I need to dispose the dbconext in the GetSubmissionDetailsAsync method?
public void ConfigureServices(IServiceCollection services)
{
services.AddScoped(provider=>provider.GetService<IMLDbContextFactory().CreateElmsDbContext());
}
public ElmsContext CreateElmsDbContext()
{
var connectionString = _configuration.GetConnectionString("elmsdatabase");
var optionsBuilder = new DbContextOptionsBuilder<ElmsContext>()
.UseSqlServer(connectionString);
return new ElmsContext(optionsBuilder.Options);
}
public class DataAccessObject : IDataAccessObject
{
private readonly ILoggerAdapter<DataAccessObject> _logger;
private readonly ElmsContext _elmsContext;
private readonly ElmsPolicyContext _elmsPolicyContext;
public DataAccessObject(ElmsContext elmsContext, ElmsPolicyContext elmsPolicyContext, ILoggerAdapter<DataAccessObject> logger)
{
_logger = logger;
_elmsContext = elmsContext;
_elmsPolicyContext = elmsPolicyContext;
}
public async Task<CertifiedBusinessSubmissionDto> GetSubmissionDetailsAsync(int? submissionId)
{
var subId = new SqlParameter("submission_id", submissionId);
var submission = await _elmsContext.CertifiedBusinessSubmissionDTO
.FromSqlRaw("EXECUTE dbo.get_info #submission_id", subId)
.ToListAsync();
return submission != null && submission.Count > 0 ? submission.FirstOrDefault() : null;
}
}

Although the DbContext implements IDisposable, you shouldn't manually dispose it, nor should you wrap it in a using statement. DbContext manages its own lifetime; when your data access request is completed, DbContext will automatically close the database connection for you.
You can check this post and the answer there is given by Diego Vega (the Senior SDE Lead on EF)
https://blog.jongallant.com/2012/10/do-i-have-to-call-dispose-on-dbcontext/
There are special cases in which dispose should be applied, but
according to the code you provided above, there is no need to explicitly apply dispose.

Related

Using Microsoft.AspNetCore.Identity.MongoDB for Multi Tenancy. How do we inject dynamic Tenant into MongoDbContext

Does anyone know how we can inject context into User Manager > MongoDB serStore at runtime in .net core 2.0.
We cannot do this at startup due to the context being dynamic but the UserStore is not accessible and UserManager has too many variables to new up, and it is wrong. Are there any solutions?
public class UserStore<TUser> :
IUserPasswordStore<TUser>,
IUserRoleStore<TUser>,
IUserLoginStore<TUser>,
IUserSecurityStampStore<TUser>,
IUserEmailStore<TUser>,
IUserClaimStore<TUser>,
IUserPhoneNumberStore<TUser>,
IUserTwoFactorStore<TUser>,
IUserLockoutStore<TUser>,
IQueryableUserStore<TUser>,
IUserAuthenticationTokenStore<TUser>
where TUser : IdentityUser
{
private readonly IMongoCollection<TUser> _Users;
//THIS IS WHERE WE WANT TO INJECT THE users AT RUNTIME
public UserStore(IMongoCollection<TUser> users)
{
_Users = users;
}
public virtual void Dispose()
{
// no need to dispose of anything, mongodb handles connection pooling automatically
}
public virtual async Task<IdentityResult> CreateAsync(TUser user, CancellationToken token)
{
await _Users.InsertOneAsync(user, cancellationToken: token);
return IdentityResult.Success;
}
unfortunately users is null at startup, and should be as the tenant has not been created at that point.
We have also been using the saaskit.Multitenancy and just can't find a solution.
Any help would be much appreciated.
Thanks
i think u need a generic repository to act as a wrapper for IMongoCollection then inject the repository inside controllers
public class Repository<T>
{
public IMongoCollection<T> Collection { get; private set; }
public Repository(IDbFactory dbFactory)
{
MongoClient client = new MongoClient("ur connection string");
this.Collection = client.GetDatabase("db").GetCollection<T>(typeof(T).Name);
}
public T Find(Expression<Func<T, bool>> filter)
{
return this.Collection.AsQueryable<T>().FirstOrDefault<T>(filter);
}
public async Task<T> FindAsync(Expression<Func<T, bool>> filter)
{
return await this.Collection.AsQueryable<T>().FirstOrDefaultAsync<T>(filter);
}
// here add more methods
}
then register the dependency as below inside Startup.cs
public void ConfigureServices(IServiceCollection services)
{
services.AddTransient(typeof(IRepository<>), typeof(Repository<>));
services.AddMvc();
}
finally inside controllers u inject the generic repository, also dont forget to Implement the IDisopsible in genereic repository
public class ProductController : Controller
{
private readonly IRepository<Product> _productRepository = null;
public ProductController(IRepository<Product> productRepository)
{
this._productRepository = productRepository;
}
}

one transaction for multiple contexts in integration tests on TestInitialize

I am writing integration tests and I want to use transaction scope.
We use EF and Repositories with Contexts.
If I have one Repository and once Context then it would look like this:
[TestInitialize]
public void RuleEngineTestsStart() {
customContext = new CustomContext();
transaction = customContext.Database.BeginTransaction();
repo = new CustomRepository(customContext);
// I need to make this context to work in the same transaction as above
anotherContext = new AnotherContext();
anotherRepo = new AnotherRepository(anotherContext);
}
At the end of tests (TestCleanup) I would like to transaction.Rollback(); everything.
I want to have the same transaction for all repositories that work with different contexts, is it possible? How to create transaction and 'send' it to all three contexts?
Please, to do not to use one Context for all repositories, it is not possible due to reasons (we want to have each context with its own DbSets later to be used within microservices).
Edit
In comments I was asked to include more code, however, I think is not necessary to answer my question.
customContext = new CustomContext();
repo = new CustomRepository(customContext);
customContext2 = new CustomContext2();
otherRepository = new CustomRepository2(customContext2);
// class to be tested needs both repositories
ToBeTestedClass cl = new ToBeTestedClass(customRepository, otherRepository);
// "BASE" interface
public interface IRepository<TEntity> where TEntity : class
{
TEntity GetById(long id);
IEnumerable<TEntity> GetByFilter(Expression<Func<TEntity, bool>> predicate);
TEntity GetSingleByFilter(Expression<Func<TEntity, bool>> filter);
void Insert(TEntity entity);
void Delete(long id);
void Update(TEntity entity);
...
}
// BASE CLASS
public class Repository<TEntity> : IRepository<TEntity> where TEntity : class
{
protected readonly DbContext _context;
protected readonly DbSet<TEntity> _dbSet;
public Repository(ColldeskDbContext context)
{
_context = context;
_dbSet = context.Set<TEntity>();
}
// GetSingle, GetAll, Insert, Update etc.
}
// CustomRepository (other Repositories are similar, with custom methods)
public interface ICustomRepository : IRepository<CusotmData>
{
// some specific methods that are not in Base class
}
public class CustomRepository: Repository<CustomData>, ICustomRepository
{
public CustomRepository(CustomContext context) : base(context)
{
}
// custom methods that are specific for given context
}
// Contexts - each context consists of its one DbSets
Don't use dbContext.SaveChanges() in your repositories. Use ONE dbContext when creating repositories. Sample:
using ( var db = new YourDbContext() )
{
// Create and begin transaction
using ( var transaction = db.Database.BeginTransaction() )
{
try
{
// ONE dbContext for all repositories
var firstRepo = new Custom1Repository(db);
var secondRepo = new Custom2Repository(db);
City city = new City { Description = "My city" };
Street street = new Street { Description = "My street", City = city};
firstRepo.Insert(city);
secondRepo.Insert(street);
// Save all your changes and after that commit transaction
db.SaveChanges();
transaction.Commit();
}
catch ( Exception ec)
{
transaction.Rollback();
}
}
}
Doing like this your repositories becomes just wrappers over DbSet<TEntity>
I have figured out that I can simply use TransactionScope like this:
private TransactionScope _scope;
[TestInitialize]
public void TestInitialize()
{
_scope = new TransactionScope();
}
[TestCleanup]
public void TestCleanup()
{
_scope.Dispose();
}
And then each Context would be running within this TransactionScope.

New DBContext in continuously running Azure WebJob

I'm having an Azure WebJob running continuously which is doing CRUD operations in my database. I'm using Entity Framework and UnitOfWork pattern and in my WebJob I use Autofac to inject my dependencies, service and repository layer. I'm having some issues with stale data when running my WebJob.
Example:
I update a record on my website and my WebJob is then kicked off but my WebJob can't see this change in the database. It sees the record prior to the change.
To fix this I tried to inject my custom context like this:
builder.RegisterType<PCContext>().As<IPCContext>().InstancePerDependency();
After doing that I can see the newest changes in the database. But now I have another issues. When I insert a new record and then read it, from my WebJob I can't see this new record. This worked fine before I injected my context (as shown in code above).
If I create a new context in my WebJob function I can read the updates from the database, but I want to use my service layer instead like this:
_services.UserExport.ExportUsers();
I can't figure out what I'm doing wrong here. Basically what I want is every time my WebJob function is kicked off I want a new context to be created so I'm sure I have the newest updates from the database and I want to be able to insert into my database and read this again in my WebJob using my service layer.
Can someone point me in the right direction?
Note that my WebJob is continuous so it's Autofac registration code is only executed once when the WebJob is start, not for every time a function in the WebJob is executed.
Please let me know if more description or code is necessary.
Thanks.
According to your description, I tested the similar scenario on my side and I found I could read and update from my database. I defined my generic Repository and UnitOfWork as follows, you could refer to them:
Repository:
public interface IRepository<T>
{
T GetById(object id);
IQueryable<T> GetAll();
void Edit(T entity);
void Insert(T entity);
void Delete(T entity);
}
public class Repository<T> : IRepository<T> where T : class
{
public DbContext context;
public DbSet<T> dbset;
public Repository(DbContext context)
{
this.context = context;
dbset = context.Set<T>();
}
public T GetById(object id)
{
return dbset.Find(id);
}
public IQueryable<T> GetAll()
{
return dbset;
}
public void Insert(T entity)
{
dbset.Add(entity);
}
public void Edit(T entity)
{
context.Entry(entity).State = EntityState.Modified;
}
public void Delete(T entity)
{
context.Entry(entity).State = EntityState.Deleted;
}
}
UnitOfWork:
public class UnitOfWork : IDisposable
{
private DbContext _context;
private Repository<TodoItem> toDoItemRepository;
public Repository<TodoItem> ToDoItemRepository
{
get
{
if (toDoItemRepository == null)
toDoItemRepository = new Repository<TodoItem>(_context);
return toDoItemRepository;
}
}
public UnitOfWork() : this(new BruceDbContext()) { }
public UnitOfWork(DbContext context)
{
_context = context;
}
public void Commit()
{
_context.SaveChanges();
}
#region Dispose
private bool disposed = false;
protected virtual void Dispose(bool disposing)
{
if (!this.disposed)
{
if (disposing)
{
_context.Dispose();
}
}
this.disposed = true;
}
public void Dispose()
{
Dispose(true);
GC.SuppressFinalize(this);
}
#endregion
}
For my WebJob I defined the Functions.cs and initialized the JobActivator as follows:
Functions.cs
public class Functions
{
private UnitOfWork _unitOfWork;
public Functions(UnitOfWork unitOfWork)
{
_unitOfWork = unitOfWork;
}
public async Task CronJob([TimerTrigger("0/30 * * * * *")] TimerInfo timer, CancellationToken cancelToken)
{
//retrieve the latest record
var item = _unitOfWork.ToDoItemRepository.GetAll().OrderByDescending(i => i.CreateDate).FirstOrDefault();
Console.WriteLine($"[{item.CreateDate}] {item.Text}");
//insert a new record
_unitOfWork.ToDoItemRepository.Insert(new Entities.TodoItem()
{
Id = Guid.NewGuid().ToString(),
CreateDate = DateTime.Now,
Text = $"hello world -{DateTime.Now}"
});
_unitOfWork.Commit();
//retrieve the previous added record
item = _unitOfWork.ToDoItemRepository.GetAll().OrderByDescending(i => i.CreateDate).FirstOrDefault();
Console.WriteLine($"[{item.CreateDate}] {item.Text}");
}
}
Program.cs
var builder = new ContainerBuilder();
builder.Register<UnitOfWork>(c => new UnitOfWork(new BruceDbContext())).InstancePerDependency();
builder.RegisterType<Functions>();
var container = builder.Build();
var config = new JobHostConfiguration()
{
JobActivator = new AutoFacJobActivator(container)
};
var host = new JobHost(config);

MsTest - Mocking a DbContext with DbContextOption and configuration

I have 2 project, Data and Data.test, I use ef core and .net core for both of them, for Data project I have ExpenseDb like this:
public class ExpenseDb: DbContext
{
private IConfigurationRoot _config;
public ExpenseDb(DbContextOptions<ExpenseDb> options, IConfigurationRoot config) : base(options)
{
_config = config;
}
public DbSet<Account> Accounts { get; set; }
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
{
base.OnConfiguring(optionsBuilder);
optionsBuilder.UseSqlServer(_config["Data:ConnectionString"]);
}
}
And I have a repository for Account like this:
private ExpenseDb _db;
public AccountRepository(ExpenseDb db)
{
_db = db;
}
public IEnumerable<Account> All(Guid userId)
{
return (_db.Accounts.AsNoTracking().Where(a => a.UserId == userId).ToList());
}
I use ms IOC for injectiong dependencies like this :
public Startup(IHostingEnvironment env)
{
var builder = new ConfigurationBuilder()
.SetBasePath(env.ContentRootPath)
.AddJsonFile("appsettings.json");
_config = builder.Build();
}
IConfigurationRoot _config;
public void ConfigureServices(IServiceCollection services)
{
services.AddSingleton(_config);
services.AddDbContext<ExpenseDb>(ServiceLifetime.Scoped);
}
These all are in my Data project, and for Data.Test I would like to test All method, I realized I must Mock my ExpenseDb so I got Moq from Nuget Package and now I have test class like this :
[TestClass]
public class AccountRepositoryTest
{
private readonly Mock<ExpenseDb> _dbMock = new Mock<ExpenseDb>();
private readonly AccountRepository _repo;
public AccountRepositoryTest()
{
_repo = new AccountRepository(_dbMock.Object);
}
[TestMethod]
public void AllForInvalidUser()
{
var fakeaccount = new Account() { Name="cat2",OpenDate=DateTime.Now,StartBalance=100};
Mock < DbSet < Account >> acMock = DbSetMock.Create(fakeaccount);
var results = _repo.All(Guid.Parse("cf15c6c9-f688-47ee-892e-297e530be053"));
Assert.IsNotNull(results);
}
}
Obviously my test is failed, because I must pass config and options to my ExpenseDb somehow, but I don't know How?!
I searched and I found out all answer are saying "You must have an inteface for your service" but i don't want to create an unnecessary interface.
Since DbContextOptions and config are not being used in the actual test code. You could create a constructor in your db context marked as protected to allow the instantiation of the ExpenseDb object without any params.

Passing connection string to Entity framework at runt time for each call

My Entity framework context is as following
public partial class MyContext : DbContext, IMyContext
{
static MyContext()
{
System.Data.Entity.Database.SetInitializer<MyContext>(null);
}
public MyContext()
: base("Name=MyContext")
{
}
I am resolving it through autofac in the following way
builder.RegisterType(typeof(MainContext)).As(typeof(DbContext)).InstancePerLifetimeScope();
builder.RegisterType<MainContext>().As<IMainContext>().InstancePerRequest();
This db context gets called in repository layer
#region Fields
private readonly IMyContext _context;
#endregion
#region Constructors and Destructors
public EmployeeRepository(IMyContext context)
{
_context = context;
}
#endregion
public void Create(Employee emp)
{
this._context.Employee.Add(emp);
}
Now my issue is , I want to set the connection string dynamically per call. The connection string will be passed through a webapi which i want to pass on to this context. Can anyone help me how can i do that? I am confused about autofac here. Secondly how can i make sure each call sets connection string and does not cache it.
You can use a factory that will build the context and set the connectionstring for you.
public interface IContextFactory
{
IContext GetInstance();
}
public class MyContextFactory : IContextFactory
{
public IContext GetInstance()
{
String connectionString = this.GetConnectionString(HttpContext.Current);
return new MyContext(connectionString);
}
private String GetConnectionString(HttpContext context)
{
// do what you want
}
}
builder.RegisterType<MyContextFactory>()
.As<IContextFactory>()
.InstancePerRequest();
builder.Register(c => c.Resolve<IContextFactory>().GetInstance())
.As<IContext>()
.InstancePerRequest();
If you can't get connectionstring based on HttpContext, you can change contextFactory implementation to expect initialization by WebAPI before creating the instance. For example :
public interface IContextFactory
{
IContext GetInstance();
void Initialize(String connectionString);
}
public class MyContextFactory : IContextFactory
{
private String _connectionString;
public void Initialize(String connectionString)
{
this._connectionString = connectionString;
}
public IContext GetInstance()
{
if (this._connectionString == null)
{
throw new Exception("connectionString not initialized");
}
return new MyContext(this._connectionString);
}
}
At the beginning of your web API call (through attribute for example), you can call the Initialize method. Because the factory is InstancePerRequest you will have one instance for the duration of the request.
By the way, I'm not sure to understand this registration
builder.RegisterType(typeof(MainContext)).As(typeof(DbContext)).InstancePerLifetimeScope();
builder.RegisterType<MainContext>().As<IMainContext>().InstancePerRequest();
It looks buggy because you will have 2 different registration of the same type and not for the same scope, is it intended ? Furthermore, it doesn't sound a good idea to register a DbContext, do you need this registration ?
The following registration looks better :
builder.RegisterType<MainContext>()
.As<IMainContext>()
.As<DbContext>()
.InstancePerRequest();