Configuration

Packages

Implementation

Singleton

using Microsoft.Extensions.Configuration;

public static class ConfigurationManager
{
    private static IConfigurationRoot _configuration;
    public static IConfigurationRoot Configuration
    {
        get
        {
            if (_configuration == null)
            {
                _configuration = new ConfigurationBuilder()
                                        .SetBasePath(AppContext.BaseDirectory)
                                        .AddJsonFile("appsettings.Development.json", optional: true, reloadOnChange: true)
                                        .AddEnvironmentVariables("AppId:")
                                        .AddUserSecrets("3490e6ac-9364-432d-9bfb-7c37692752cb")
                                        .Build();
            }
            return _configuration;
        }
    }
}

Usage

ConfigurationManager.Configuration["SomeConfig"]

Code Sample

.NET Console App

 var configuration = new ConfigurationBuilder()
                                        .SetBasePath(AppContext.BaseDirectory)
                                        .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
                                        .Build();

ASP.NET

private static ConfigurationManager GetConfiguration(ConfigurationManager configurationManager)
{
    configurationManager
                 .SetBasePath(AppContext.BaseDirectory)
                 .AddJsonFile("appsettings.json", optional: false, reloadOnChange: true)
                 .AddJsonFile($"appsettings.Development.json", optional: true, reloadOnChange: true)
                 .AddEnvironmentVariables("AppPrefix:")
                 .Build();

    return configurationManager;
}

Add Configuration File to csproj

<ItemGroup>
    <None Update="appsettings.json">
        <CopyToOutputDirectory>Always</CopyToOutputDirectory>
    </None>
</ItemGroup>

Cross-Platform Support

The : separator doesn't work with environment variable hierarchical keys on all platforms. __, the double underscore, is supported by all platforms.

:warning: WARNING
`AppPrefix:ModuleConfiguration:Infrastructure:Redis:Port` would need to be translated to `AppPrefix__ModuleConfiguration__Infrastructure__Redis__Port`

Set Environment Variable

:warning: WARNING
When creating/removing Environment Variables, Visual Studio MUST be restarted to pick up the changes.

setx Lambda__ModuleConfiguration__Infrastructure__Cognito__ValidIssuer "SOME VALUE" /M
setx Lambda__ModuleConfiguration__Infrastructure__Cognito__ClientId "SOME VALUE" /M
setx ASPNETCORE_ENVIRONMENT "Development" /M or setx ASPNETCORE_ENVIRONMENT "Staging" /M or setx ASPNETCORE_ENVIRONMENT "Production" /M

Safe storage of app secrets in development

Add a reference to the Microsoft.Extensions.Configuration.UserSecrets package
Navigate to your .NET project folder
Run dotnet user-secrets init (one-off per project)
Run dotnet user-secrets set "Segment:WriteKey" "some-write-key"
Read the value in your application

var configuration = new ConfigurationBuilder().AddUserSecrets("[ID obtained from step 3]").Build();
var value = configuration["Segment:SomeConfig"];

Values are stored on C:\Users\<username>\AppData\Roaming\Microsoft\UserSecrets

Documentation

Troubleshooting

Issue: ASP.NET Core: AddEnvironmentVariables doesn't load variables
Cause: You probably just declared your Environment Variables hence Visual Studio does not see them.
Resolution: Restart your Visual Studio.