/// <summary>
/// Gets the ID of an existing firewall.
/// </summary>
/// <param name="client">The FirewallClient to use to obtain the firewall
/// ID.</param>
/// <param name="name">The name of the firewall to obtain the ID for.</param>
/// <returns>The firewall ID if it exists. Returns an empty string if no firewall
/// exists with the given <paramref name="name"/>.</returns>
public static string GetExistingFirewall(this FirewallClient client, string name)
{
var existingFirewalls = client.GetFirewallGroups();
bool Predicate(KeyValuePair <string, FirewallGroup> existingFirewall) =>
existingFirewall.Value.description == name;
if (existingFirewalls.FirewallGroups == null ||
!existingFirewalls.FirewallGroups.Exists(Predicate))
{
return("");
}
var(existingFirewallGroupId, _) =
existingFirewalls.FirewallGroups.Single(Predicate);
return(existingFirewallGroupId);
}