DockerSecrets.Configuration

Overview

DockerSecrets.Configuration is a lightweight NuGet package that seamlessly integrates Docker secrets into your .NET configuration system. This provider reads secrets from a mounted Docker secrets directory (defaulting to /run/secrets), processes secret file names based on configurable namespaces and custom delimiters, and loads them as key-value pairs into your application configuration.

The package supports filtering secrets by multiple namespaces and can optionally include secrets without a namespace, giving you complete control over how secrets are imported into your application.

Features

Docker Secrets Integration: Load secrets directly from a mounted directory into your configuration.
Namespace Filtering: Filter secrets using one or multiple namespaces.
Customizable Delimiters: Configure namespace and key delimiters for flexible file naming conventions.
Empty Namespace Inclusion: Optionally include secrets that do not have a namespace.

Installation

Install the package via the .NET CLI:

dotnet add package DockerSecrets.Configuration

Or via the Package Manager Console:

Install-Package DockerSecrets.Configuration

For more details, visit the NuGet package page.

Usage

Basic Example

Add the Docker secrets configuration provider to your configuration builder. For instance, in your Program.cs or Startup.cs:

using DockerSecrets.Configuration;
using Microsoft.Extensions.Configuration;
using System.IO;

var builder = new ConfigurationBuilder()
    .SetBasePath(Directory.GetCurrentDirectory())
    .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
    .AddDockerSecrets(); // Uses default parameters: secretsPath = "/run/secrets"

// Build the configuration
var configuration = builder.Build();

// Access a secret value (assuming a file named "ApplicationSettings__EncryptionKey")
var encryptionKey = configuration["ApplicationSettings:EncryptionKey"];

Using Multiple Namespaces

You can filter secrets by specific namespaces and control whether to include secrets without a namespace:

using DockerSecrets.Configuration;
using Microsoft.Extensions.Configuration;
using System.IO;

var builder = new ConfigurationBuilder()
    .SetBasePath(Directory.GetCurrentDirectory())
    .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
    .AddDockerSecrets(
        secretsPath: "/run/secrets",
        expectedNamespaces: new[] { "Test", "Production" },
        namespaceDelimiter: ".",
        keyDelimiter: "__",
        includeEmptyNamespace: false);

var configuration = builder.Build();

In this example, only secrets with file names beginning with Test. or Production. will be loaded, and secrets with no namespace will be excluded.

API Documentation

AddDockerSecrets Extension Method

public static IConfigurationBuilder AddDockerSecrets(
    this IConfigurationBuilder builder,
    string secretsPath = "/run/secrets",
    IEnumerable<string> expectedNamespaces = null,
    string namespaceDelimiter = ".",
    string keyDelimiter = "__",
    bool includeEmptyNamespace = false)

Parameters:

builder: The configuration builder to which the provider is added.
secretsPath: The directory path where Docker secrets are mounted.
expectedNamespaces: A collection of namespaces to filter secrets. If null or empty, secrets without a namespace are automatically included.
namespaceDelimiter: The delimiter that separates the namespace from the key in a secret file name.
keyDelimiter: The delimiter used to transform the secret file name into a configuration key.
includeEmptyNamespace: Indicates whether to include secrets without a namespace. Defaults to false unless no namespaces are provided.