Oip.Settings 2.0.0

Oip.Settings

Application settings with an EF Core provider. Sources in order of priority:

• Command line argument
• Environment variables
• JSON file
• EF Core

Startup

1. Create a settings class

public class AppSettings : BaseAppSettings<AppSettings>
{
    public string TestString { get; set; } = "test";
    public int TestInt { get; set; } = 1;
}

2. Initialize settings with a ConnectionString from a JSON file, a command line argument or elsewhere

public class Program
{
    public static void Main(string[] args)
    {
        // Initialize settings 
        AppSettings.Initialize(args);

        var builder = WebApplication.CreateBuilder(args);
        // Add settings db context
        builder.Services.AddAppSettingsDbContext(AppSettings.Instance);
        
        var app = builder.Build();
        app.MapGet("/", () => $"AppSettings.Instance.TestInt: {AppSettings.Instance.TestInt}");

        app.Run();
    }
}

Connection string as a model

ConnectionString is written as a plain string in appsettings.json, but is available in code as a ConnectionModel:

{
  "ConnectionString": "XpoProvider=SQLite;Data Source=settings.db"
}

AppSettings.Instance.ConnectionString.Provider;                  // XpoProvider.SQLite
AppSettings.Instance.ConnectionString.NormalizeConnectionString; // Data Source=settings.db
AppSettings.Instance.ConnectionString.ConnectionString;          // XpoProvider=SQLite;Data Source=settings.db

ConnectionString is typed as ConnectionModel and is the single place where the parsed connection string lives. The former Provider, NormalizedConnectionString and Connection properties are removed, use ConnectionString.Provider and ConnectionString.NormalizeConnectionString instead.

ConnectionModel has a TypeConverter, so any own property of this type is bound from a plain string too:

public class AppSettings : BaseAppSettings<AppSettings>
{
    public ConnectionModel ReportConnection { get; set; } = default!;
}

{
  "ReportConnection": "XpoProvider=Postgres;Server=localhost;Database=report;"
}

Sensitive data logging

SensitiveDataLogging is a custom connection string parameter, just like XpoProvider. It is stripped from the normalized connection string and turns on EF Core sensitive data logging for the settings DbContext:

{
  "ConnectionString": "XpoProvider=SQLite;SensitiveDataLogging=true;Data Source=settings.db"
}

AppSettings.Instance.ConnectionString.SensitiveDataLogging;      // true
AppSettings.Instance.ConnectionString.NormalizeConnectionString; // Data Source=settings.db

Do not enable it in production: EF Core will then write parameter values into the log.

Running tests

Run all tests

dotnet test ./src/Oip.Settings.sln

Run tests that don't need external services

dotnet test ./src/Oip.Settings.sln --filter "TestCategory!=Integration"

Run only tests that need external services

dotnet test ./src/Oip.Settings.sln --filter "TestCategory=Integration"