Simulating Genesys Cloud EventBridge Consumer Failures via EventBridge API with C#

What You Will Build

• A C# console application that orchestrates controlled failure simulations against Genesys Cloud EventBridge destinations to validate consumer resilience and dead letter queue behavior.
• The application uses the Genesys Cloud EventBridge REST API (/api/v2/eventbridge/destinations, /api/v2/eventbridge/destinations/{id}/status) and OAuth 2.0 Client Credentials flow.
• The tutorial covers C# 10+ with System.Net.Http, System.Text.Json, and async/await patterns for production-grade API orchestration.

Prerequisites

• OAuth Client: Genesys Cloud API client with Client Credentials grant type.
• Required Scopes: eventbridge:destination:read, eventbridge:destination:write, eventbridge:subscription:read
• API Version: Genesys Cloud REST API v2 (EventBridge)
• Runtime: .NET 8.0 or later
• Dependencies: System.Text.Json, System.Net.Http, Microsoft.Extensions.Logging.Abstractions (optional, standard logging used here)

Authentication Setup

Genesys Cloud uses OAuth 2.0 for API authentication. The Client Credentials flow exchanges an API key and secret for an access token. Tokens expire after a fixed duration, so the implementation includes automatic refresh logic and HTTP 401 interception.

using System;
using System.Collections.Generic;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;
using System.Text.Json.Serialization;
using System.Threading;
using System.Threading.Tasks;

namespace EventBridgeChaosSimulator
{
    public class GenesysAuthService : IDisposable
    {
        private readonly HttpClient _httpClient;
        private readonly string _baseUrl;
        private readonly string _apiKey;
        private readonly string _apiSecret;
        private string? _accessToken;
        private DateTime _tokenExpiry;
        private readonly object _lock = new();

        public GenesysAuthService(string baseUrl, string apiKey, string apiSecret)
        {
            _baseUrl = baseUrl.TrimEnd('/');
            _apiKey = apiKey;
            _apiSecret = apiSecret;
            _httpClient = new HttpClient
            {
                Timeout = TimeSpan.FromSeconds(30)
            };
        }

        public async Task<string> GetAccessTokenAsync()
        {
            lock (_lock)
            {
                if (_accessToken != null && DateTime.UtcNow < _tokenExpiry.AddSeconds(-30))
                {
                    return _accessToken;
                }
            }

            var payload = new Dictionary<string, string>
            {
                ["grant_type"] = "client_credentials",
                ["client_id"] = _apiKey,
                ["client_secret"] = _apiSecret
            };

            var content = new FormUrlEncodedContent(payload);
            var request = new HttpRequestMessage(HttpMethod.Post, $"{_baseUrl}/oauth/token")
            {
                Content = content
            };

            var response = await _httpClient.SendAsync(request);
            response.EnsureSuccessStatusCode();

            var json = await response.Content.ReadAsStringAsync();
            var tokenResponse = JsonSerializer.Deserialize<Dictionary<string, JsonElement>>(json);
            _accessToken = tokenResponse["access_token"].GetString()!;
            var expiresIn = tokenResponse["expires_in"].GetInt32();
            _tokenExpiry = DateTime.UtcNow.AddSeconds(expiresIn);

            return _accessToken;
        }

        public async Task<HttpResponseMessage> ExecuteAsync(HttpRequestMessage request)
        {
            var token = await GetAccessTokenAsync();
            request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", token);
            request.Headers.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));

            var response = await _httpClient.SendAsync(request);

            if (response.StatusCode == System.Net.HttpStatusCode.Unauthorized)
            {
                await GetAccessTokenAsync();
                request.Headers.Authorization = new AuthenticationHeaderValue("Bearer", _accessToken!);
                return await _httpClient.SendAsync(request);
            }

            return response;
        }

        public void Dispose()
        {
            _httpClient.Dispose();
        }
    }
}

Implementation

Step 1: Payload Construction & Schema Validation

Genesys Cloud EventBridge destinations require strict schema compliance. The simulation constructs a destination payload with a controlled target URL that will intentionally fail, enabling retry and dead letter queue observation. The validation logic enforces maximum chaos test duration limits and verifies required fields before submission.

public record DestinationPayload(
    [property:JsonPropertyName("name")] string Name,
    [property:JsonPropertyName("type")] string Type,
    [property:JsonPropertyName("configuration")] DestinationConfiguration Configuration,
    [property:JsonPropertyName("is_enabled")] bool IsEnabled
);

public record DestinationConfiguration(
    [property:JsonPropertyName("endpoint_url")] string EndpointUrl,
    [property:JsonPropertyName("headers")] Dictionary<string, string> Headers,
    [property:JsonPropertyName("retry_policy")] RetryPolicyConfiguration RetryPolicy
);

public record RetryPolicyConfiguration(
    [property:JsonPropertyName("max_retries")] int MaxRetries,
    [property:JsonPropertyName("retry_interval_seconds")] int RetryIntervalSeconds
);

public static class PayloadValidator
{
    public static void Validate(DestinationPayload payload, int maxSimulationDurationMinutes)
    {
        if (string.IsNullOrWhiteSpace(payload.Name) || payload.Name.Length > 255)
            throw new ArgumentException("Destination name must be 1-255 characters.");
        
        if (!new[] { "webhook", "kafka", "sqs", "kinesis" }.Contains(payload.Type, StringComparer.OrdinalIgnoreCase))
            throw new ArgumentException("Invalid destination type. Supported: webhook, kafka, sqs, kinesis.");
        
        if (string.IsNullOrWhiteSpace(payload.Configuration.EndpointUrl))
            throw new ArgumentException("Endpoint URL is required for failure simulation.");
        
        if (maxSimulationDurationMinutes > 60)
            throw new ArgumentException("Chaos simulation duration cannot exceed 60 minutes to prevent prolonged state corruption.");
        
        if (payload.Configuration.RetryPolicy.MaxRetries < 0 || payload.Configuration.RetryPolicy.MaxRetries > 10)
            throw new ArgumentException("Retry policy max_retries must be between 0 and 10.");
    }
}

Step 2: Fault Injection & State Rollback Logic

The simulation executes atomic POST operations to create the destination, then immediately monitors its status. A failure injection matrix controls the sequence of state changes (enabled/disabled, retry policy adjustments). Automatic state rollback triggers ensure the destination returns to a safe configuration after the simulation window closes.

public class ChaosOrchestrator
{
    private readonly GenesysAuthService _auth;
    private readonly string _baseUrl;
    private readonly JsonSerializerOptions _jsonOptions = new() { PropertyNamingPolicy = JsonNamingPolicy.CamelCase, DefaultIgnoreCondition = JsonIgnoreCondition.WhenWritingNull };

    public ChaosOrchestrator(GenesysAuthService auth, string baseUrl)
    {
        _auth = auth;
        _baseUrl = baseUrl;
    }

    public async Task<string> DeploySimulationTargetAsync(DestinationPayload payload, CancellationToken ct)
    {
        var json = JsonSerializer.Serialize(payload, _jsonOptions);
        var content = new StringContent(json, Encoding.UTF8, "application/json");
        var request = new HttpRequestMessage(HttpMethod.Post, $"{_baseUrl}/api/v2/eventbridge/destinations")
        {
            Content = content
        };

        var response = await _auth.ExecuteAsync(request);
        if (response.StatusCode == System.Net.HttpStatusCode.TooManyRequests)
        {
            await HandleRateLimitAsync(response, ct);
            response = await _auth.ExecuteAsync(request);
        }

        response.EnsureSuccessStatusCode();
        var resultJson = await response.Content.ReadAsStringAsync();
        var result = JsonSerializer.Deserialize<Dictionary<string, JsonElement>>(resultJson);
        return result["id"].GetString()!;
    }

    public async Task UpdateDestinationStateAsync(string destinationId, bool isEnabled, int retryInterval, CancellationToken ct)
    {
        var payload = new Dictionary<string, JsonElement>
        {
            ["is_enabled"] = JsonValue.Create(isEnabled),
            ["configuration"] = JsonDocument.Parse($"{{\"retry_policy\": {{\"retry_interval_seconds\": {retryInterval}}}}}").RootElement
        };

        var json = JsonSerializer.Serialize(payload, _jsonOptions);
        var content = new StringContent(json, Encoding.UTF8, "application/json");
        var request = new HttpRequestMessage(HttpMethod.Put, $"{_baseUrl}/api/v2/eventbridge/destinations/{destinationId}")
        {
            Content = content
        };

        var response = await _auth.ExecuteAsync(request);
        response.EnsureSuccessStatusCode();
    }

    private async Task HandleRateLimitAsync(HttpResponseMessage response, CancellationToken ct)
    {
        var retryAfterHeader = response.Headers.RetryAfter?.Delta;
        var waitTime = retryAfterHeader ?? TimeSpan.FromSeconds(5);
        Console.WriteLine($"Rate limited. Waiting {waitTime.TotalSeconds} seconds.");
        await Task.Delay(waitTime, ct);
    }
}

Step 3: DLQ Verification, Latency Tracking & Audit Logging

Resilient architecture requires observing dead letter queue accumulation and retry policy verification. This step polls the EventBridge status endpoint, calculates latency between failure injection and recovery, and writes structured audit logs for stability governance.

public record StatusMetrics(
    [property:JsonPropertyName("last_successful_delivery")] DateTime? LastSuccessfulDelivery,
    [property:JsonPropertyName("last_failed_delivery")] DateTime? LastFailedDelivery,
    [property:JsonPropertyName("retry_count")] int RetryCount,
    [property:JsonPropertyName("dead_letter_queue_count")] int DlqCount,
    [property:JsonPropertyName("status")] string Status
);

public class ResilienceMonitor
{
    private readonly GenesysAuthService _auth;
    private readonly string _baseUrl;
    private readonly JsonSerializerOptions _jsonOptions = new() { PropertyNamingPolicy = JsonNamingPolicy.CamelCase };
    private readonly List<Dictionary<string, object>> _auditLog = new();

    public ResilienceMonitor(GenesysAuthService auth, string baseUrl)
    {
        _auth = auth;
        _baseUrl = baseUrl;
    }

    public async Task<StatusMetrics> PollStatusAsync(string destinationId, CancellationToken ct)
    {
        var request = new HttpRequestMessage(HttpMethod.Get, $"{_baseUrl}/api/v2/eventbridge/destinations/{destinationId}/status");
        var response = await _auth.ExecuteAsync(request);
        
        if (response.StatusCode == System.Net.HttpStatusCode.TooManyRequests)
        {
            var retryAfter = response.Headers.RetryAfter?.Delta ?? TimeSpan.FromSeconds(2);
            await Task.Delay(retryAfter, ct);
            response = await _auth.ExecuteAsync(request);
        }

        response.EnsureSuccessStatusCode();
        var json = await response.Content.ReadAsStringAsync();
        return JsonSerializer.Deserialize<StatusMetrics>(json, _jsonOptions)!;
    }

    public void RecordAuditEvent(string destinationId, string eventType, string details, double latencyMs)
    {
        var entry = new Dictionary<string, object>
        {
            ["timestamp"] = DateTime.UtcNow.ToString("o"),
            ["destination_id"] = destinationId,
            ["event_type"] = eventType,
            ["details"] = details,
            ["latency_ms"] = latencyMs
        };
        _auditLog.Add(entry);
        Console.WriteLine($"[AUDIT] {eventType}: {details} (Latency: {latencyMs:F2}ms)");
    }

    public string ExportAuditLog()
    {
        return JsonSerializer.Serialize(_auditLog, new JsonSerializerOptions { WriteIndented = true });
    }
}

Step 4: External Callback Synchronization & Recovery Tracking

The simulation exposes callback handlers to synchronize with external chaos engineering platforms. It tracks recovery success rates by comparing injected failure states against observed status transitions, enforcing maximum chaos test duration limits.

public class ChaosSimulationRunner
{
    private readonly ChaosOrchestrator _orchestrator;
    private readonly ResilienceMonitor _monitor;
    private readonly Action<string, Dictionary<string, object>>? _externalCallback;

    public ChaosSimulationRunner(ChaosOrchestrator orchestrator, ResilienceMonitor monitor, Action<string, Dictionary<string, object>>? externalCallback = null)
    {
        _orchestrator = orchestrator;
        _monitor = monitor;
        _externalCallback = externalCallback;
    }

    public async Task RunAsync(DestinationPayload payload, int durationMinutes, CancellationToken ct)
    {
        var stopwatch = Stopwatch.StartNew();
        var maxDuration = TimeSpan.FromMinutes(durationMinutes);
        
        _monitor.RecordAuditEvent("simulation", "start", "Chaos simulation initiated", 0);
        var destinationId = await _orchestrator.DeploySimulationTargetAsync(payload, ct);
        _monitor.RecordAuditEvent(destinationId, "deploy", "Destination created for failure injection", stopwatch.Elapsed.TotalMilliseconds);

        // Failure injection matrix: disable destination, trigger retry exhaustion
        await Task.Delay(TimeSpan.FromSeconds(5), ct);
        await _orchestrator.UpdateDestinationStateAsync(destinationId, isEnabled: false, retryInterval: 2, ct);
        _monitor.RecordAuditEvent(destinationId, "inject_failure", "Destination disabled to simulate consumer failure", stopwatch.Elapsed.TotalMilliseconds);

        // Monitor DLQ accumulation and retry behavior
        var dlqThresholdReached = false;
        while (!dlqThresholdReached && stopwatch.Elapsed < maxDuration && !ct.IsCancellationRequested)
        {
            var status = await _monitor.PollStatusAsync(destinationId, ct);
            _monitor.RecordAuditEvent(destinationId, "status_poll", $"Retry: {status.RetryCount}, DLQ: {status.DlqCount}", stopwatch.Elapsed.TotalMilliseconds);

            if (_externalCallback != null)
            {
                _externalCallback.Invoke(destinationId, new Dictionary<string, object>
                {
                    ["status"] = status.Status,
                    ["dlq_count"] = status.DlqCount,
                    ["retry_count"] = status.RetryCount
                });
            }

            if (status.DlqCount > 0)
            {
                dlqThresholdReached = true;
                _monitor.RecordAuditEvent(destinationId, "dlq_triggered", "Dead letter queue threshold reached", stopwatch.Elapsed.TotalMilliseconds);
            }

            await Task.Delay(TimeSpan.FromSeconds(10), ct);
        }

        // Automatic state rollback
        await _orchestrator.UpdateDestinationStateAsync(destinationId, isEnabled: true, retryInterval: 5, ct);
        _monitor.RecordAuditEvent(destinationId, "rollback", "Destination re-enabled, retry policy reset", stopwatch.Elapsed.TotalMilliseconds);
        _monitor.RecordAuditEvent("simulation", "end", "Chaos simulation completed", stopwatch.Elapsed.TotalMilliseconds);

        Console.WriteLine(_monitor.ExportAuditLog());
    }
}

Complete Working Example

The following script combines all components into a single executable console application. Replace the environment variables with your Genesys Cloud API credentials before execution.

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Text.Json;
using System.Text.Json.Serialization;
using System.Threading;
using System.Threading.Tasks;

namespace EventBridgeChaosSimulator
{
    // [Insert GenesysAuthService class from Authentication Setup]
    // [Insert PayloadValidator, DestinationPayload, DestinationConfiguration, RetryPolicyConfiguration records]
    // [Insert ChaosOrchestrator class]
    // [Insert StatusMetrics, ResilienceMonitor classes]
    // [Insert ChaosSimulationRunner class]

    class Program
    {
        static async Task Main(string[] args)
        {
            var baseUrl = Environment.GetEnvironmentVariable("GENESYS_BASE_URL") ?? "https://api.mypurecloud.com";
            var apiKey = Environment.GetEnvironmentVariable("GENESYS_API_KEY") ?? throw new InvalidOperationException("GENESYS_API_KEY not set.");
            var apiSecret = Environment.GetEnvironmentVariable("GENESYS_API_SECRET") ?? throw new InvalidOperationException("GENESYS_API_SECRET not set.");
            var targetUrl = Environment.GetEnvironmentVariable("SIMULATION_TARGET_URL") ?? "https://httpbin.org/status/500";

            using var auth = new GenesysAuthService(baseUrl, apiKey, apiSecret);
            var orchestrator = new ChaosOrchestrator(auth, baseUrl);
            var monitor = new ResilienceMonitor(auth, baseUrl);

            var payload = new DestinationPayload(
                Name: "ChaosTest-Destination-" + Guid.NewGuid().ToString("N")[..8],
                Type: "webhook",
                Configuration: new DestinationConfiguration(
                    EndpointUrl: targetUrl,
                    Headers: new Dictionary<string, string> { ["X-Simulation-Source"] = "ChaosEngine" },
                    RetryPolicy: new RetryPolicyConfiguration(MaxRetries: 3, RetryIntervalSeconds: 5)
                ),
                IsEnabled: true
            );

            PayloadValidator.Validate(payload, maxSimulationDurationMinutes: 10);

            var externalPlatformCallback = new Action<string, Dictionary<string, object>>((id, metrics) =>
            {
                Console.WriteLine($"[EXTERNAL CALLBACK] Destination {id} metrics: {JsonSerializer.Serialize(metrics)}");
            });

            var runner = new ChaosSimulationRunner(orchestrator, monitor, externalPlatformCallback);

            Console.WriteLine("Starting EventBridge Chaos Simulation...");
            await runner.RunAsync(payload, durationMinutes: 5, CancellationToken.None);
            Console.WriteLine("Simulation complete. Audit log exported to console.");
        }
    }
}

Common Errors & Debugging

Error: 401 Unauthorized

• What causes it: The API key or secret is incorrect, or the token has expired and the refresh logic failed.
• How to fix it: Verify credentials in your Genesys Cloud admin console under Development > API Access. Ensure the GetAccessTokenAsync method is called before every request batch. The provided implementation handles automatic 401 retry.
• Code showing the fix: The ExecuteAsync method in GenesysAuthService already intercepts 401 responses, forces a token refresh, and retries the original request.

Error: 403 Forbidden

• What causes it: The OAuth client lacks eventbridge:destination:write or eventbridge:destination:read scopes.
• How to fix it: Navigate to Development > API Access in Genesys Cloud, edit the API client, and add the required EventBridge scopes. Regenerate the access token.
• Code showing the fix: No code change is required. Verify the token payload contains the correct scopes using JsonSerializer.Deserialize<Dictionary<string, JsonElement>>(json)["scope"].GetString().

Error: 429 Too Many Requests

• What causes it: Exceeding Genesys Cloud rate limits (typically 10 requests per second per client for EventBridge endpoints).
• How to fix it: Implement exponential backoff or respect the Retry-After header. The HandleRateLimitAsync method in ChaosOrchestrator parses the header and delays execution accordingly.
• Code showing the fix: The polling loop in RunAsync uses Task.Delay between status checks. The HandleRateLimitAsync method ensures compliance with server-imposed throttling.

Error: 400 Bad Request

• What causes it: Payload schema violation. Common issues include invalid destination types, missing endpoint_url, or retry policy values outside the 0-10 range.
• How to fix it: Run PayloadValidator.Validate() before submission. Ensure type matches supported values and retry_interval_seconds is positive.
• Code showing the fix: The PayloadValidator.Validate method throws descriptive ArgumentException messages that map directly to Genesys Cloud schema constraints.

Error: 5xx Server Error

• What causes it: Temporary Genesys Cloud platform instability or EventBridge engine saturation.
• How to fix it: Implement circuit breaker logic. The simulation enforces maxSimulationDurationMinutes to prevent indefinite loops. Retry with exponential backoff if the error persists beyond 30 seconds.
• Code showing the fix: Add a retry wrapper around DeploySimulationTargetAsync that catches HttpRequestException and delays for TimeSpan.FromSeconds(Math.Pow(2, attempt)).

Official References

• Genesys Cloud EventBridge Destinations API
• OAuth 2.0 Client Credentials Flow
• EventBridge Destination Status & Metrics
• Rate Limiting & Retry Guidelines