ASP.NET Core 1.0 ConfigurationBuilder().AddJsonFile("appsettings.json"); not finding file

Question

So I've finally got round to looking at Core and I've fallen at the first hurdle. I'm following the Pluralsight ASP.NET Core Fundamentals course and I'm getting an exception when trying too add the appsettings.json file to the configuration builder.

public Startup()
{
    var builder = new ConfigurationBuilder()
        .AddJsonFile("appsettings.json");

    Configuration = builder.Build();
}

The error I'm getting is The configuration file 'appsettings.json' was not found and is not optional. But I have created the directly under my solution just like in the course video.

score 26 · Accepted Answer · answered Jul 09 '16 at 14:16

26

public Startup(IHostingEnvironment env)
{
    var builder = new ConfigurationBuilder()
        .SetBasePath(env.ContentRootPath)
        .AddJsonFile("appsettings.json");

    Configuration = builder.Build();
}

This seems to do the trick. However unsure this is the proper way to do it. Kinda feels like a hack.

answered Jul 09 '16 at 14:16

Zhorian

802
1
9
15

3

I was able to get it to work using .SetBasePath(Directory.GetCurrentDirectory()), as shown here: http://benfoster.io/blog/how-to-configure-kestrel-urls-in-aspnet-core-rc2 – Sako73 Aug 23 '16 at 14:18
1

Well, if it IS a hack, it's a hack the Microsoft does themselves when you set up a new blank ASP.NET Core Web Application. – David Jan 06 '17 at 18:03

score 22 · Answer 2 · answered Jul 29 '16 at 20:51

22

You need to add the package below:

    "Microsoft.Extensions.Configuration.Json": "1.0.0"

answered Jul 29 '16 at 20:51

user6655970

229
1
4

This was what i was missing. Thanks! – tedi Dec 06 '17 at 07:35

score 16 · Answer 3 · answered Sep 15 '16 at 12:34

Another way:

appsettings.json:

{
    "greeting": "A configurable hello, to you!"
}

Startup.cs:

using Microsoft.Extensions.Configuration; // for using IConfiguration
using System.IO; // for using Directory

public class Startup
{
    public IConfiguration Configuration { get; set; }

    public Startup()
    {
        var builder = new ConfigurationBuilder();
        builder.SetBasePath(Directory.GetCurrentDirectory());
        builder.AddJsonFile("appsettings.json");

        Configuration = builder.Build();
    }    
}

In the Configure method:

app.Run(async (context) =>
{
    // Don't use:
    // string greeting = Configuration["greeting"]; // null

    string greeting = Configuration.GetSection("greeting").Value;
    await context.Response.WriteAsync(greeting)
});

Thank you! `builder.SetBasePath(Directory.GetCurrentDirectory());` fixed it for me. — w0ns88, Dec 11 '18 at 09:18

score 9 · Answer 4 · answered Jul 25 '16 at 15:55

9

An alternative solution I found from this blog post works as well. It has the added benefit of not needing to modify the Startup.cs file's Startup method signature.

In the buildOptions section add copyToOutput with the name of the file.

{
  "version": "1.0.0-*",
  "buildOptions": {
    "emitEntryPoint": true,
    "copyToOutput": "appsettings.json"
  },
  .... The rest of the file goes here ....

answered Jul 25 '16 at 15:55

Dzejms

3,108
2
30
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1

If you don't have project.json; don't worry. It is dumped, more detail on [here](https://stackoverflow.com/questions/42779524/there-is-no-project-json-global-json-etc-on-net-core-solution-with-visual) – Beytan Kurt Aug 01 '18 at 12:49

bhatt ravii · Answer 5 · 2019-07-17T05:36:58.513

Actually for this you need to provide root path from your environment variable so you need to pass IHostingEnvironment reference to provide root path:

public Startup(IHostingEnvironment env)
{
    var builder = new ConfigurationBuilder()
                          .SetBasePath(env.ContentRootPath)
                          .AddJsonFile("appsettings.json");
    Configuration = builder.Build();
}

and if you can't find AddJsonFile method then you have to add using Microsoft.Extensions.Configuration.Json;

score 7 · Answer 6 · answered Jan 04 '19 at 18:36

7

Right click appsettings.json -> Properties, then makes sure that Copy to Output Directory is set to "Copy Always"

answered Jan 04 '19 at 18:36

user3413723

11,147
6
55
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score 5 · Answer 7 · answered Mar 25 '18 at 23:13

In .NET Core 2.0, you would update the .csproj file to copy the JSON file to the output directory so that it can be accessed, like so:

<ItemGroup>
    <Folder Include="wwwroot\" />
    <None Include="appsettings.json" CopyToOutputDirectory="Always" />
</ItemGroup>

score 1 · Answer 8 · answered Nov 08 '17 at 19:37

The answers that suggest adding .SetBasePath(env.ContentRootPath) in Startup.cs depend upon a prior step.

First, add the line .UseContentRoot(Directory.GetCurrentDirectory()) to your WebHostBuilder construction in Program.cs like so:

public class Program
{
    public static void Main(string[] args)
    {
        var config = new ConfigurationBuilder()
            .SetBasePath(Directory.GetCurrentDirectory())
            .AddEnvironmentVariables()
            .Build();

        var host = new WebHostBuilder()
            .UseConfiguration(config)
            .UseKestrel()
            .UseContentRoot(Directory.GetCurrentDirectory())
            .UseStartup<Startup>()
            .Build();

        host.Run();
    }
}

Then the following will work:

public Startup(IHostingEnvironment env)
{
    var builder = new ConfigurationBuilder()
        .SetBasePath(env.ContentRootPath)
        .AddJsonFile("appsettings.json");

    Configuration = builder.Build();
}

score 0 · Answer 9 · answered Sep 15 '17 at 16:47

If you have done anything with Project Debug Properties, then you may have inadvertently overwritten the starting directory:

Project -> Right-click -> Properties -> Debug -> Profile and then look at the entry in Working Directory.

The simplest is that it be blank.

ASP.NET Core 1.0 ConfigurationBuilder().AddJsonFile("appsettings.json"); not finding file

9 Answers9