Data type 'varchar' is not supported in this form

[mikes-gh]

Just changed to the new AspNetCore packages on vnext with vs 2015 update2 rc
The below used to work before this. I was on the last known good packages before the name change on vnext.

I have a derived DbContext which sets a database depending on a routing value as below

using Microsoft.AspNetCore.Http;
using Microsoft.AspNetCore.Routing;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Infrastructure;
using Microsoft.Extensions.Configuration;

namespace Reports2.Models
{
    public class TradingCompanyDbContext:ReportingDbContext
    {
        private readonly IConfiguration _config;
        private readonly IHttpContextAccessor _httpContextAccessor;
        public TradingCompanyDbContext(IConfiguration config, IHttpContextAccessor httpContextAccessor,DbContextOptions options):base(options)
        {
            _config = config;
            _httpContextAccessor = httpContextAccessor;            
        }

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            var tradingCompany = _httpContextAccessor.HttpContext.GetRouteValue("tradingCompany");
            if (tradingCompany != null)
            {
                var connectionString = _config["Data:" + tradingCompany + ":ConnectionString"];
                optionsBuilder.UseSqlServer(connectionString);
            }
        }
    }
}

It seems whenever I use this context I am getting

NotSupportedException: Data type 'varchar' is not supported in this form. Either specify the length explicitly in the type name, for example as 'varchar(16)', or remove the data type and use APIs such as HasMaxLength to allow EF choose the data type

Any ideas.
This is a preliminary inquiry . I realise a repro would be best but maybe its a known thing before I go down that road

[ajcvickers]

Are you specifying the store type "varchar" in a data annotation or in OnModelCreating? If so, change it as suggested in the message. If not, then please post your model classes and any code you have in OnModelCreating.

See this PR : #4500, and also this open issue: #3420

[mikes-gh]

Ok the on model creating was scafolded a while back by reveng . I see hascolumntype is varchar (note no length) and hasmaxlength as length. I presume this has changed now? Shall I re reveng or is there a new dotnet cli tool now.

[lajones]

The RevEng tool has been updated to produce the right results - see #4348. Or you can just change the code manually to specify e.g. HasColumnType("varchar(<length>)").

[mikes-gh]

Ok thanks it's a lot of fields so I'll reveng again. I'll do it tomorrow and close this if it all goes ok.

[mikes-gh]

OK I had to manually change (long job) this because I couldn't get donet ef to work or dnx ef.

Probably due to the flux at the moment.
Im going to open another issue for that

Thanks for your help

[lajones]

Sorry - it is a problem at the moment (hopefully fixed soon). But I should have said that the Scaffold-DbContext powershell command within Visual Studio has been working consistently even when the command line dotnet ef command does not. If you run into trouble again that might help you.

[MalithRukshan]

I also got the same error: =>{Data type 'varchar' is not supported in this form. Either specify the length explicitly in the type name, for example as 'varchar(16)', or remove the data type and use APIs such as HasMaxLength to allow EF choose the data type.'}

before fixed :
.HasColumnType("varchar")
.HasMaxLength(50);
solution is:
.HasColumnType("varchar(50)");

It is working.