Health Checks

Monitor your Toggly SDK connection status using ASP.NET Core Health Checks.

Installation

Install the Toggly.FeatureManagement.HealthChecks package:

Install-Package Toggly.FeatureManagement.HealthChecks

Basic Setup

Add the health check to your application:

builder.Services.AddHealthChecks()
    .AddTogglyHealthCheck();

Configuration Options

Staleness Threshold

Configure how long definitions can go without updates when WebSocket is disconnected:

builder.Services.AddHealthChecks()
    .AddTogglyHealthCheck(options =>
    {
        options.StalenessThreshold = TimeSpan.FromMinutes(15);
    });

info

Definitions are only considered stale when both conditions are true:

• WebSocket is disconnected
• Definitions haven't been refreshed within the threshold

When WebSocket is connected, updates are pushed in real-time so age doesn't matter.

Required Features

Specify features whose definitions must contain an AlwaysOn filter for your service to be considered healthy. This checks environment-level definitions; it does not evaluate the current user, percentage rollout, or Order:

builder.Services.AddHealthChecks()
    .AddTogglyHealthCheck(options =>
    {
        options.RequiredFeatures = new[] { "payment-gateway", "critical-feature" };
    });

If any required feature is disabled, the health check reports Degraded status.

Treat Required Features as Unhealthy

For critical features, you can make disabled features report Unhealthy instead:

builder.Services.AddHealthChecks()
    .AddTogglyHealthCheck(options =>
    {
        options.RequiredFeatures = new[] { "payment-gateway" };
        options.TreatRequiredFeaturesAsUnhealthy = true;
    });

Full Configuration Example

builder.Services.AddHealthChecks()
    .AddTogglyHealthCheck(
        name: "toggly-sdk",
        tags: new[] { "ready" },
        configure: options =>
        {
            options.StalenessThreshold = TimeSpan.FromMinutes(15);
            options.RequiredFeatures = new[] { "critical-feature", "payment-gateway" };
            options.TreatRequiredFeaturesAsUnhealthy = false;
            options.IncludeDiagnosticData = true;
        });

Health Check States

Status	Condition
Healthy	SDK loaded, definitions fresh, all required features enabled
Degraded	Required features are disabled
Unhealthy	SDK not loaded, or definitions stale with WebSocket disconnected

Response Data

When IncludeDiagnosticData is enabled (default), the health check includes detailed information:

{
  "status": "Healthy",
  "results": {
    "toggly": {
      "status": "Healthy",
      "description": "Toggly SDK is healthy",
      "data": {
        "appKey": "*** abc123",
        "environment": "Production",
        "definitionCount": 15,
        "websocketConnected": true,
        "loaded": true,
        "lastDefinitionsCheck": "2024-01-15T10:30:00.0000000Z"
      }
    }
  }
}

Available Data Fields

Field	Description
appKey	App key masked to its last six characters (keys of six characters or fewer are unchanged)
environment	The configured environment name
definitionCount	Number of loaded feature definitions
websocketConnected	Whether the WebSocket for live updates is connected
loaded	Whether the SDK has completed initial load
lastDefinitionsCheck	Timestamp of the last successful definitions check, including an unchanged HTTP 304 response
lastError	Most recent error message (if any)
lastErrorTime	Timestamp of most recent error (if any)
disabledRequiredFeatures	List of required features that are disabled

Kubernetes Integration

Use health checks with Kubernetes readiness and liveness probes:

// Configure health check with tags
builder.Services.AddHealthChecks()
    .AddTogglyHealthCheck(
        name: "toggly",
        tags: new[] { "ready" });

// Map health check endpoints
app.MapHealthChecks("/health/ready", new HealthCheckOptions
{
    Predicate = check => check.Tags.Contains("ready")
});

app.MapHealthChecks("/health/live", new HealthCheckOptions
{
    Predicate = _ => false // Liveness doesn't include Toggly
});

In your Kubernetes deployment:

livenessProbe:
  httpGet:
    path: /health/live
    port: 80
  initialDelaySeconds: 10
  periodSeconds: 10

readinessProbe:
  httpGet:
    path: /health/ready
    port: 80
  initialDelaySeconds: 5
  periodSeconds: 5

Shorthand for Required Features

If you only need to specify required features, use the shorthand overload:

builder.Services.AddHealthChecks()
    .AddTogglyHealthCheck(
        requiredFeatures: new[] { "critical-feature", "payment-gateway" },
        name: "toggly-features");

Configuration Options Reference

Option	Type	Default	Description
StalenessThreshold	TimeSpan	10 minutes	Max age before definitions are stale (when WebSocket disconnected)
RequiredFeatures	IEnumerable<string>	Empty	Features whose definitions must contain an AlwaysOn filter
TreatRequiredFeaturesAsUnhealthy	bool	false	Report Unhealthy instead of Degraded for disabled features
IncludeDiagnosticData	bool	true	Include detailed data in health check response

Working example

Explore the .NET SDK Sample. Its guided sections include the first flag, request identity, Order VIP targeting, filter presets, named variants, Hangfire, health checks, and OpenAPI filtering. The README maps each section to its source files and includes a manual walkthrough.