Creates a random RSA key used for signing jwt tokens. Also exports the public key in PEM format.

randomrsa.cs

private static (string publicKeyPem, SigningCredentials signingCredentials) GenerateRamdomRsaKeyPair()
{
	SigningCredentials signingCredentials = null;
	string publicKeyPem;

	using (RSA rsa = RSA.Create())
	{
		rsa.KeySize = 4096;
		var rsaParams = rsa.ExportParameters(false);

		var rsaSecurityKey = new RsaSecurityKey(rsa);
		signingCredentials = new SigningCredentials(rsaSecurityKey, SecurityAlgorithms.RsaSha256);

		using (var stream = new MemoryStream())
		using (var writer = new PemWriter(stream))
		{
			writer.WritePublicKey(rsaParams);

			stream.Seek(0, SeekOrigin.Begin);

			using (var reader = new StreamReader(stream, Encoding.UTF8))
			{
				publicKeyPem = reader.ReadToEnd();
			}
		}
	}

	return (publicKeyPem, signingCredentials);
}