Asv.Cfg

Asv.Cfg stores typed configuration objects under string keys. It provides a common API for in-memory values, a folder of JSON files, a single JSON file, a package part, and ZIP entries. All public types use the Asv.Cfg namespace.

Installation

dotnet add package Asv.Cfg

The project currently targets net10.0 through src/Directory.Build.props. It uses Newtonsoft.Json, R3 notifications, Asv.Common lifetime helpers, and file-system abstractions.

First configuration

using Asv.Cfg;

using var configuration = new InMemoryConfiguration();
var settings = configuration.Get<ConnectionSettings>();
settings.Host = "localhost";
configuration.Set(settings);

public sealed class ConnectionSettings
{
    public string Host { get; set; } = "127.0.0.1";
    public int Port { get; set; } = 7341;
}

The type-based overload uses ConnectionSettings as its key. Loading an absent key stores the default object. Changing the returned object alone does not save it: call Set or Update explicitly.

Choose a backend

Backend	Representation	Appropriate use
`InMemoryConfiguration`	JSON tokens held in memory	Tests and temporary settings
`JsonConfiguration`	One `<key>.json` file per value	Independently editable configuration sections
`JsonOneFileConfiguration`	One JSON object containing all keys	A single application settings file
`JsonPackageConfiguration`	One JSON object in a `Package` part	Settings embedded in an existing package
`ZipJsonConfiguration`	One `<key>.json` entry per value	Portable ZIP settings bundles
`ZipJsonVersionedFile`	ZIP settings plus `FileInfo.json`	Bundles with a file type and maximum supported version

These backends share operations, but differ in notifications on default creation, persistence timing, and ownership. Choose based on the details below rather than assuming they are interchangeable in every respect.

Guides

Configuration serialization is not encryption. Keep credentials in an appropriate secret store and avoid writing configuration values to logs.

Source and verification

Sources are under src/Asv.Cfg; tests are under src/Asv.Cfg.Test.

dotnet build src/Asv.Cfg/Asv.Cfg.csproj
dotnet test src/Asv.Cfg.Test/Asv.Cfg.Test.csproj

26 October 2026