EF Core con errore di stringa di connessione di Postgres

Sto provando ad usare ASP.net Core insieme a Postgres per la prima volta. Stavo seguendo ( http://dotnetthoughts.net/using-postgresql-with-aspnet-core/ ) questo post del blog per creare la mia prima migrazione. Ho già creato un database nel mio posgresSQL chiamato asp_api_test.

Le mie dotnet ef migrations add Initial avuto successo. Tuttavia, quando dotnet ef database update mi sono imbattuto in un errore. Il Format of the initialization string does not conform to specification starting at index 0

Le mie appsettings.json:

{
  "ConnectionStrings": {
    "DataAccessPostgreSqlProvider": "Host=localhost;Username=postgres;Password=root;Database=asp_trial_api;Pooling=true;"
  },
  "Logging": {
    "IncludeScopes": false,
    "LogLevel": {
      "Default": "Debug",
      "System": "Information",
      "Microsoft": "Information"
    }
  }
}

Suppongo che la mia stringa di connessione non sia corretta. Il mio startup.cs:

public void ConfigureServices(IServiceCollection services)
        {
            // Add framework services.
            services.AddApplicationInsightsTelemetry(Configuration);

            services.AddDbContext<WebAPIDataContext>(options => {
                options.UseNpgsql("DataAccessPostgreSqlProvider", b => b.MigrationsAssembly("New_Api"));
            });

            services.AddMvc();
        }

Il mio progetto.json:

{
  "dependencies": {
    "Microsoft.NETCore.App": {
      "version": "1.0.0",
      "type": "platform"
    },
    "Microsoft.AspNetCore.Mvc": "1.0.0",
    "Microsoft.AspNetCore.Server.IISIntegration": "1.0.0",
    "Microsoft.AspNetCore.Server.Kestrel": "1.0.0",
    "Microsoft.Extensions.Configuration.EnvironmentVariables": "1.0.0",
    "Microsoft.Extensions.Configuration.FileExtensions": "1.0.0",
    "Microsoft.Extensions.Configuration.Json": "1.0.0",
    "Microsoft.Extensions.Configuration.CommandLine": "1.0.0",
    "Microsoft.Extensions.Logging": "1.0.0",
    "Microsoft.Extensions.Logging.Console": "1.0.0",
    "Microsoft.Extensions.Logging.Debug": "1.0.0",
    "Microsoft.Extensions.Options.ConfigurationExtensions": "1.0.0",
    "Microsoft.EntityFrameworkCore": "1.0.0",
    "Microsoft.EntityFrameworkCore.Design": "1.0.0-preview2-final",
    "Microsoft.EntityFrameworkCore.Tools": {
      "version": "1.0.0-preview1-final",
      "imports": [
        "portable-net45+win8+dnxcore50",
        "portable-net45+win8"
      ]
    },
    "Npgsql.EntityFrameworkCore.PostgreSQL": "1.0.0",
    "Microsoft.ApplicationInsights.AspNetCore": "2.0.0"
  },

  "tools": {
    "Microsoft.AspNetCore.Server.IISIntegration.Tools": "1.0.0-preview2-final",
    "Microsoft.EntityFrameworkCore.Tools": "1.0.0-preview2-final"
  },

  "frameworks": {
    "netcoreapp1.0": {
      "imports": [
        "dotnet5.6",
        "portable-net45+win8"
      ]
    }
  },

  "buildOptions": {
    "emitEntryPoint": true,
    "preserveCompilationContext": true
  },

  "runtimeOptions": {
    "configProperties": {
      "System.GC.Server": true
    }
  },

  "publishOptions": {
    "include": [
      "wwwroot",
      "**/*.cshtml",
      "appsettings.json",
      "web.config"
    ]
  },

  "scripts": {
    "postpublish": [ "dotnet publish-iis --publish-folder %publish:OutputPath% --framework %publish:FullTargetFramework%" ]
  }
}

Che cosa sto facendo di sbagliato?