I'm trying to integrate LaunchDarkly into my project. I'm seeing a problem where the LdClient connects in one version and doesn't in another. The code is essentially identical. I got their example running via a simple Console app in .NET Framework 4.8 using the Server SDK. You can find a version of it here. This is what my working project looks like:
using System;
using System.Net.Sockets;
using System.Runtime.Remoting.Contexts;
using LaunchDarkly.Sdk;
using LaunchDarkly.Sdk.Server;
using Context = LaunchDarkly.Sdk.Context;
namespace HelloDotNet
{
class Program
{
// Set SdkKey to your LaunchDarkly SDK key.
public const string SdkKey = "my-sdk-key";
// Set FeatureFlagKey to the feature flag key you want to evaluate.
public const string FeatureFlagKey = "my-flag";
private static void ShowMessage(string s)
{
Console.WriteLine("*** " + s);
Console.WriteLine();
}
static void Main(string[] args)
{
var ldConfig = Configuration.Default(SdkKey);
var client = new LdClient(ldConfig);
if (client.Initialized)
{
ShowMessage("SDK successfully initialized!");
}
else
{
ShowMessage("SDK failed to initialize");
Environment.Exit(1);
}
// Set up the evaluation context. This context should appear on your LaunchDarkly contexts
// dashboard soon after you run the demo.
var context = Context.Builder("test")
.Name("Sandy")
.Build();
var flagValue = client.BoolVariation(FeatureFlagKey, context, false);
ShowMessage(string.Format("Feature flag '{0}' is {1} for this context",
FeatureFlagKey, flagValue));
// Here we ensure that the SDK shuts down cleanly and has a chance to deliver analytics
// events to LaunchDarkly before the program exits. If analytics events are not delivered,
// the context attributes and flag usage statistics will not appear on your dashboard. In
// a normal long-running application, the SDK would continue running and events would be
// delivered automatically in the background.
client.Dispose();
Console.ReadKey();
}
}
}
However, if I then transfer that code to just a class in a ClassLibrary, the LdClient never connects and client.Initalized is always false. In turn, this means I can never see my flags toggle. For example, the client in this Singleton never connects:
using LaunchDarkly.Sdk.Server;
using System;
using LaunchDarkly.Sdk;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Xml.Linq;
using Context = LaunchDarkly.Sdk.Context;
namespace FeatureFlags
{
public class FeatureFlagsManager
{
//Load from something better in the future, hardcoded for now
private readonly string _sdkKey = "my-sdk-key";
private Configuration _ldConfig;
private LdClient _ldClient;
private Context _context;
private static readonly Lazy<FeatureFlagsManager> lazy = new Lazy<FeatureFlagsManager>(() => new FeatureFlagsManager());
public static FeatureFlagsManager Instance => lazy.Value;
private FeatureFlagsManager()
{
_ldConfig = Configuration.Default(_sdkKey);
_ldClient = new LdClient(_ldConfig);
//load key and name from something in the future
_context = Context.Builder("test").Name("Sandy").Build();
}
public bool GetFeatureFlagBool(string featureFlagKey)
{
bool enabled = _ldClient.BoolVariation(featureFlagKey, _context, false);
return enabled;
}
}
}
I also observe that if I turn the first, working example into a class library and put the contents of main into a method and try to run the method, the client does not initialize.
