YamlConfigurationProvider

YamlConfigurationProvider represents a .yaml file as configuration source.

// IConfigurationSource
var configurationSource = new YamlConfigurationProvider.Source
{
    FileProvider = new PhysicalFileProvider(Directory.GetCurrentDirectory()),
    Path = "appsettings.yaml",
    ReloadOnChange = true,
    Optional = true
};
// IConfigurationProvider
IConfigurationProvider configurationProvider = new YamlConfigurationProvider(configurationSource);
// Create configuration
IConfiguration configuration = new ConfigurationBuilder()
    .Add(configurationSource)
    .Build();

YamlConfigurationExtensions

.AddYamlFile(path, optional, reloadOnChange) extension method adds a yaml file to IConfigurationBuilder.

// Create configuration
IConfiguration configuration = new ConfigurationBuilder()
    .AddYamlFile("appsettings.yaml", optional: true, reloadOnChange: true)
    .Build();

Same extension method works with IHostBuilder.

// Create host
IHost host =
    new HostBuilder()
        .ConfigureDefaults(null)
        .ConfigureAppConfiguration(cb => cb.AddYamlFile("appsettings.yaml", optional: true, reloadOnChange: true))
        .Build();
// Get configuration
IConfiguration configuration = host.Services.GetRequiredService<IConfiguration>();

YamlNodeExtensions

.ToYaml(properties, policy, targetRoot?, delimiter) is creates a YamlNode to match contents of 'properties'.

// Create properties
var properties = new Dictionary<string, string?>
{
        { "Cars:0:License", "ABC-123" },
        { "Cars:0:Owner", "Donald" },
        { "Cars:0:PreviousOwners:0", "Mickey" },
        { "Cars:0:PreviousOwners:1", "Goofy" },
        { "Cars:1:License", "XYZ-456" },
        { "Cars:1:Owner", "Mickey" },
        { "Cars:1:PreviousOwners:0", "Pluto" },
        { "Cars:2:License", "YYY-444" },
        { "Cars:2:Owner", "Scrooge" },
};

// Convert 'properties' to a YamlNode
YamlNode root = YamlNodeExtensions.ToYaml(
    properties: properties,
    policy: YamlNodeExtensions.CorrelatePolicy.RemoveUnusedNodes | YamlNodeExtensions.CorrelatePolicy.RemoveAmbiguentNodes,
    targetRoot: null,
    delimiter: ':');

// Convert to yaml document
var stringWriter = new StringWriter();
YamlDocument yamlDocument = new YamlDocument(root);
YamlStream yamlStream = new YamlStream(yamlDocument);
yamlStream.Save(stringWriter, assignAnchors: false);
string text = stringWriter.ToString();
// Print
Console.WriteLine(text);

Cars:
- License: ABC-123
  Owner: Donald
  PreviousOwners:
  - Mickey
  - Goofy
- License: XYZ-456
  Owner: Mickey
  PreviousOwners:
  - Pluto
- License: YYY-444
  Owner: Scrooge
...

Method can also synchronize an existing 'targetRoot' to match with the contents of 'properties' key-values.

// Donald sells car to Minnie
properties["Cars:0:Owner"] = "Minnie";
properties["Cars:0:PreviousOwners:2"] = "Donald";
// Scrooge's car is scrapped
properties.Remove("Cars:2:License");
properties.Remove("Cars:2:Owner");

// Synchronize modifications to the already existing 'root' node
root = YamlNodeExtensions.ToYaml(
    properties: properties,
    policy: YamlNodeExtensions.CorrelatePolicy.RemoveUnusedNodes | YamlNodeExtensions.CorrelatePolicy.RemoveAmbiguentNodes,
    targetRoot: root,
    delimiter: ':');

// Reprint document
stringWriter = new StringWriter();
yamlDocument = new YamlDocument(root);
yamlStream = new YamlStream(yamlDocument);
yamlStream.Save(stringWriter, assignAnchors: false);
text = stringWriter.ToString();
// Print
Console.WriteLine(text);

Cars:
- License: ABC-123
  Owner: Minnie
  PreviousOwners:
  - Mickey
  - Goofy
  - Donald
- License: XYZ-456
  Owner: Mickey
  PreviousOwners:
  - Pluto
...

CorrelatePolicy determines synchronization policy.

[Flags]
public enum CorrelatePolicy
{
    RemoveUnusedNodes = 1,
    RemoveAmbiguentNodes = 2,
}

Full Example

Full example

using Avalanche.Configuration;
using Microsoft.Extensions.Configuration;
using Microsoft.Extensions.DependencyInjection;
using Microsoft.Extensions.FileProviders;
using Microsoft.Extensions.Hosting;
using YamlDotNet.RepresentationModel;

public class yaml
{
    public static void Run()
    {
        {
            // <01>
            // IConfigurationSource
            var configurationSource = new YamlConfigurationProvider.Source
            {
                FileProvider = new PhysicalFileProvider(Directory.GetCurrentDirectory()),
                Path = "appsettings.yaml",
                ReloadOnChange = true,
                Optional = true
            };
            // IConfigurationProvider
            IConfigurationProvider configurationProvider = new YamlConfigurationProvider(configurationSource);
            // Create configuration
            IConfiguration configuration = new ConfigurationBuilder()
                .Add(configurationSource)
                .Build();
            // </01>
            Console.WriteLine(configuration.PrintTree());
        }

        {
            // <11>
            // Create configuration
            IConfiguration configuration = new ConfigurationBuilder()
                .AddYamlFile("appsettings.yaml", optional: true, reloadOnChange: true)
                .Build();
            // </11>
            // Print configuration
            Console.WriteLine(configuration.PrintTree());
        }
        {
            // <12>
            // Create host
            IHost host =
                new HostBuilder()
                    .ConfigureDefaults(null)
                    .ConfigureAppConfiguration(cb => cb.AddYamlFile("appsettings.yaml", optional: true, reloadOnChange: true))
                    .Build();
            // Get configuration
            IConfiguration configuration = host.Services.GetRequiredService<IConfiguration>();
            // </12>
            // Print configuration
            Console.WriteLine(configuration.PrintTree());
        }

        {
            // <21>
            // Create properties
            var properties = new Dictionary<string, string?>
            {
                    { "Cars:0:License", "ABC-123" },
                    { "Cars:0:Owner", "Donald" },
                    { "Cars:0:PreviousOwners:0", "Mickey" },
                    { "Cars:0:PreviousOwners:1", "Goofy" },
                    { "Cars:1:License", "XYZ-456" },
                    { "Cars:1:Owner", "Mickey" },
                    { "Cars:1:PreviousOwners:0", "Pluto" },
                    { "Cars:2:License", "YYY-444" },
                    { "Cars:2:Owner", "Scrooge" },
            };

            // Convert 'properties' to a YamlNode
            YamlNode root = YamlNodeExtensions.ToYaml(
                properties: properties,
                policy: YamlNodeExtensions.CorrelatePolicy.RemoveUnusedNodes | YamlNodeExtensions.CorrelatePolicy.RemoveAmbiguentNodes,
                targetRoot: null,
                delimiter: ':');

            // Convert to yaml document
            var stringWriter = new StringWriter();
            YamlDocument yamlDocument = new YamlDocument(root);
            YamlStream yamlStream = new YamlStream(yamlDocument);
            yamlStream.Save(stringWriter, assignAnchors: false);
            string text = stringWriter.ToString();
            // Print
            Console.WriteLine(text);
            // </21>

            // <22>
            // Donald sells car to Minnie
            properties["Cars:0:Owner"] = "Minnie";
            properties["Cars:0:PreviousOwners:2"] = "Donald";
            // Scrooge's car is scrapped
            properties.Remove("Cars:2:License");
            properties.Remove("Cars:2:Owner");

            // Synchronize modifications to the already existing 'root' node
            root = YamlNodeExtensions.ToYaml(
                properties: properties,
                policy: YamlNodeExtensions.CorrelatePolicy.RemoveUnusedNodes | YamlNodeExtensions.CorrelatePolicy.RemoveAmbiguentNodes,
                targetRoot: root,
                delimiter: ':');

            // Reprint document
            stringWriter = new StringWriter();
            yamlDocument = new YamlDocument(root);
            yamlStream = new YamlStream(yamlDocument);
            yamlStream.Save(stringWriter, assignAnchors: false);
            text = stringWriter.ToString();
            // Print
            Console.WriteLine(text);
            // </22>
        }
    }
}