Table of Contents

RandomValue Provider

Sometimes, you might need to generate random values as part of your application's configuration values.

The Steeltoe RandomValue generator is a configuration provider that you can use to do just that. It can produce integers, longs, uuids, or strings, as the following examples show:

var my_secret = config["random:value"];
var my_number = config["random:int"];
var my_big_number = config["random:long"];
var my_uuid = config["random:uuid"];
var my_number_less_than_ten = config["random:int(10)"];
var my_number_in_range = config["random:int[1024,65536]"];

You can also use the generator together with property placeholders. For example, consider the following appsettings.json:

{
    "my": {
        "secret": "${random:value}",
        "number": "${random:int}",
        "big_number": "${random:long}",
        "uuid": "${random:uuid}",
        "number_less_than_ten": "${random:int(10)}",
        "number_in_range": "${random:int[1024,65536]}"
    }
}

Usage

You should have a good understanding of how the .NET Configuration services work before starting to use this provider.

In order to use the Steeltoe RandomValue provider, you need to:

  1. Add a NuGet package reference to your project.
  2. Add the provider to the Configuration Builder.
  3. Access random values from the IConfiguration.

Add NuGet Reference

To use the provider, you need to add a reference to the appropriate Steeltoe NuGet.

To do so, add a PackageReference resembling the following:

<ItemGroup>
...
    <PackageReference Include="Steeltoe.Extensions.Configuration.RandomValueBase" Version="3.2.0"/>
...
</ItemGroup>

Add Configuration Provider

To have the ability to generate random values from the configuration, you need to add the RandomValue generator provider to the ConfigurationBuilder.

The following example shows how to do so:

using Steeltoe.Extensions.Configuration.RandomValue;
...

var builder = new ConfigurationBuilder()
    .SetBasePath(env.ContentRootPath)
    .AddJsonFile("appsettings.json", optional: true, reloadOnChange: true)
    .AddJsonFile($"appsettings.{env.EnvironmentName}.json", optional: true)

    // Add RandomValue generator
    .AddRandomValueSource();
Configuration = builder.Build();
...

If you wish to generate random values as part of using placeholders, you need to add the RandomValue provider to the builder before you add the placeholder resolver.

Access Random Value Data

Once the configuration has been built, the RandomValue generator can be used to generate values. You can access the configuration data by using the appropriate random keys.

Consider the following HomeController example:

public class HomeController : Controller
{
    private IConfiguration _config;
    public HomeController(IConfiguration config)
    {
        _config = config;
    }
    public IActionResult Index()
    {
        ViewData["random:int"] = _config["random:int"];
        ViewData["random:long"] = _config["random:long"];
        ViewData["random:int(10)"] = _config["random:int(10)"];
        ViewData["random:long(100)"] = _config["random:long(100)"];
        ViewData["random:int(10,20)"] = _config["random:int(10,20)"];
        ViewData["random:long(100,200)"] = _config["random:long(100,200)"];
        ViewData["random:uuid"] = _config["random:uuid"];
        ViewData["random:string"] = _config["random:string"];
        return View();
    }
    ...
}