ASP.NET Web API server code connects to database when run locally, but not when hosted on Azure

Question

I created a REST API using ASP.NET Web API, Entity Framework and a SQL database hosted on Microsoft Azure. I used Code first migration.

Here is the User Model class

namespace Trivio.Models
{
    public partial class User
    {
        public int Id { get; set; }
        public string FirstName { get; set; }
        public string LastName { get; set; }
        public string Email { get; set; }
        public string Password { get; set; }
    }
}

DbContext defined under Trivio.Models.ApplicationDbContext.cs

namespace Trivio.Models
{
    public class ApplicationDbContext : IdentityDbContext<ApplicationUser>
    {

        public DbSet<User> UserInformation { get; set; }
        public DbSet<Trivia> Trivia { get; set; }
        public DbSet<TriviaHistoryModel> TriviaHistoryModel { get; set; }
        public ApplicationDbContext()
            : base("DefaultConnection", throwIfV1Schema: false)
        {
        }
        public static ApplicationDbContext Create()
        {
            return new ApplicationDbContext();
        }

    }
}

First I created migrations, locally on a localDB. Then I updated my server code to Azure and enabled code first migrations. I know this works because my Azure SQL database populated with correct data. To test if my database was hosted correctly, I updated the connectionString to connect to the Azure SQL database

Here is the connection string under Web.config. (I have replaced password and username with dummy data)

<connectionStrings>
    <add name="DefaultConnection" connectionString="Server=tcp:trivioserver.database.windows.net,1433;Initial Catalog=Trivio;Persist Security Info=False;User ID={mycorrectusername};Password={mypassword};MultipleActiveResultSets=False;Encrypt=True;TrustServerCertificate=False;Connection Timeout=30;" providerName="System.Data.SqlClient"/>
  </connectionStrings>

My user API controller under Trivio.Controllers.UserController.cs:

namespace Trivio.Controllers
{
    [RoutePrefix("Trivia")]
    public class UserController : ApiController
    {
        private ApplicationDbContext _context;
        public UserController()
        {
            _context = new ApplicationDbContext();
        }
        //------------Routes---------------------------------------------
        //Return List of Users
        [HttpGet]
        [Route("Users")]
        public IEnumerable<User> GetUsers()
        {
            return _context.UserInformation.ToList();

        }
    }
}

Here's where the problem arises. When I run the code on my local server and make a GET call to localserver/Trivia/Users correct list of users from my Azure SQL database is returned.

However, After publishing to Azure, the exact same code returns an empty list of Users. I made a GET call to http://{myappname}.azurewebsites.net/Trivia/Users.

<ArrayOfUser xmlns:i="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://schemas.datacontract.org/2004/07/Trivio.Models"/>

I know the code is correctly hosted because html code is loaded.

My ServiceConfigurationCloud file under Trivio.Azure

<?xml version="1.0" encoding="utf-8"?>
    <ServiceConfiguration serviceName="Trivio.Azure" xmlns="http://schemas.microsoft.com/ServiceHosting/2008/10/ServiceConfiguration" osFamily="4" osVersion="*" schemaVersion="2015-04.2.6">
      <Role name="Trivio">
        <Instances count="1" />
        <ConfigurationSettings>
          <Setting name="Microsoft.WindowsAzure.Plugins.Diagnostics.
                " value="UseDevelopmentStorage=true" />
        </ConfigurationSettings>
      </Role>
    </ServiceConfiguration>

I know that the database is not empty, because I manually checked it and the local server code connected to same database returns correct information.

Answer 1

I'm with Steve G on that. I think the easy way to identify / fix this problem is use the remote debugger and inspect what is wrong:

https://docs.microsoft.com/en-us/azure/app-service-web/web-sites-dotnet-troubleshoot-visual-studio