How to use user secrets in a dotnet core test project

Question

I want to store a database connection string for my integration tests as a user secret. My project.json looks like this:

{
  ...

  "dependencies": {
    ...
    "Microsoft.Extensions.Configuration.UserSecrets": "1.1.0"        
  },

  "tools": {
    "Microsoft.Extensions.SecretManager.Tools": "1.1.0-preview4-final"
  },

  "userSecretsId": "dc5b4f9c-8b0e-4b99-9813-c86ce80c39e6"
}

I've added the following to the constructor of my test class:

IConfigurationBuilder configurationBuilder = new ConfigurationBuilder()
    .AddJsonFile("appsettings.json")
    .AddUserSecrets();

However when I run the tests the following exception is thrown when it hits that line:

An exception of type 'System.InvalidOperationException' occurred in Microsoft.Extensions.Configuration.UserSecrets.dll but was not handled in user code

Additional information: Could not find 'UserSecretsIdAttribute' on assembly 'dotnet-test-nunit, Version=3.4.0.0, Culture=neutral, PublicKeyToken=null'.

Have I missed something or is what I'm trying to do not supported?

Answer 1

See instructions in https://patrickhuber.github.io/2017/07/26/avoid-secrets-in-dot-net-core-tests.html, in particular in InitialiseTest add

// the type specified here is just so the secrets library can 
            // find the UserSecretId we added in the csproj file
            var builder = new ConfigurationBuilder()
                .AddUserSecrets<HttpClientTests>();

            Configuration = builder.Build()

However note that it will not allow to run tests on build server

Answer 2

You must specify the UserSecretsId in Startup of your application.

[assembly: UserSecretsId("xxx")]
namespace myapp
{
    public class Startup
    {
    ...

Then you have to use the overload of .AddUserSecrets(Assembly assembly) in your test project. Example:

.AddUserSecrets(typeof(Startup).GetTypeInfo().Assembly)

Source: https://stackoverflow.com/a/40775511/5270073

Answer 3

For settings you can use appsettings.json, not the project.json. It looks like this:

{
    "userSecretsId": "dc5b4f9c-8b0e-4b99-9813-c86ce80c39e6"
}

Make sure to copy the file to output by changing the project.json:

"buildOptions": {
    "copyToOutput": "appsettings.json"
}

Now you can retrieve the secret like this:

[Fact]
public MyTest()
{
    var appSettings = new ConfigurationBuilder()
        .SetBasePath(Directory.GetCurrentDirectory())
        .AddJsonFile("appsettings.json")
        .Build();

    var secret = appSettings["userSecretsId"]
}