Compensating Genesys Cloud EventBridge Failed Deliveries with Go

What You Will Build

• A Go service that intercepts Genesys Cloud EventBridge payloads, validates delivery state, and executes atomic compensating transactions when downstream processing fails.
• Uses the Genesys Cloud REST API for connection validation and standard HTTP for the compensation webhook pipeline.
• Covers Go 1.21+ with net/http, crypto/sha256, and the official Genesys Cloud Go SDK.

Prerequisites

• Genesys Cloud OAuth2 Client Credentials client with eventbridge:connection:read and eventbridge:stream:read scopes
• Genesys Cloud API v2 (/api/v2/eventbridge/connections, /api/v2/eventbridge/streams)
• Go 1.21 or later
• External dependencies: github.com/genesyscloud/go, github.com/prometheus/client_golang/prometheus, github.com/google/uuid

Authentication Setup

Genesys Cloud requires OAuth2 Client Credentials flow for server-to-server API access. The following code initializes the authentication client, caches the access token, and handles automatic refresh when the token expires.

package main

import (
	"context"
	"crypto/tls"
	"fmt"
	"net/http"
	"time"

	"github.com/genesyscloud/go"
)

type AuthConfig struct {
	ClientID     string
	ClientSecret string
	BaseURL      string
}

type TokenStore struct {
	AccessToken string
	ExpiresAt   time.Time
}

func NewGenesysClient(cfg AuthConfig) (*go.PlatformClient, error) {
	config := go.NewConfiguration()
	config.BasePath = cfg.BaseURL
	config.OAuth.AccessToken = ""
	config.OAuth.RefreshToken = ""
	config.OAuth.ClientID = cfg.ClientID
	config.OAuth.ClientSecret = cfg.ClientSecret
	config.OAuth.Scopes = []string{"eventbridge:connection:read", "eventbridge:stream:read"}

	// Configure HTTP client with retry and TLS settings
	httpClient := &http.Client{
		Timeout: 30 * time.Second,
		Transport: &http.Transport{
			TLSClientConfig: &tls.Config{MinVersion: tls.VersionTLS12},
		},
	}
	config.HTTPClient = httpClient

	platformClient, err := go.NewPlatformClient(cfg.ClientID, cfg.ClientSecret, cfg.BaseURL)
	if err != nil {
		return nil, fmt.Errorf("failed to initialize Genesys client: %w", err)
	}

	// Force initial token fetch
	_, err = platformClient.GetOAuthClient().GetToken(context.Background())
	if err != nil {
		return nil, fmt.Errorf("oauth token acquisition failed: %w", err)
	}

	return platformClient, nil
}

The SDK handles token caching internally. When the token expires, subsequent API calls trigger an automatic refresh. You must ensure the client credentials possess the required scopes. Missing scopes return HTTP 403.

Implementation

Step 1: Validate EventBridge Connection & Load Delivery Constraints

Before processing compensation logic, the service must verify the EventBridge connection exists and retrieve delivery constraints. This step prevents compensating against misconfigured or disabled streams.

package main

import (
	"context"
	"fmt"
	"log"

	"github.com/genesyscloud/go"
)

type EventBridgeConstraints struct {
	MaximumCompensationRetryCount int
	AllowedEventTypes             []string
	EnableRollbackDirective       bool
}

func ValidateConnection(ctx context.Context, client *go.PlatformClient, connectionID string) (*go.EventbridgeConnection, *EventBridgeConstraints, error) {
	api := go.NewEventbridgeApi(client)
	connection, resp, err := api.GetEventbridgeConnection(ctx, connectionID)
	if err != nil {
		if resp != nil && resp.StatusCode == 404 {
			return nil, nil, fmt.Errorf("eventbridge connection %s not found", connectionID)
		}
		if resp != nil && resp.StatusCode == 429 {
			log.Printf("Rate limited on connection validation. Retrying in 2s...")
			time.Sleep(2 * time.Second)
			return ValidateConnection(ctx, client, connectionID)
		}
		return nil, nil, fmt.Errorf("connection validation failed: %w", err)
	}

	if connection.State != "active" {
		return nil, nil, fmt.Errorf("connection %s is not active", connectionID)
	}

	constraints := &EventBridgeConstraints{
		MaximumCompensationRetryCount: 3,
		AllowedEventTypes:             []string{"conversation/created", "conversation/updated", "interaction/completed"},
		EnableRollbackDirective:       true,
	}

	return &connection, constraints, nil
}

Expected Response:

{
  "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "name": "production-eventbridge",
  "state": "active",
  "urls": ["https://your-compensator.example.com/webhook"],
  "streams": ["conversation/created", "conversation/updated"]
}

The retry logic handles HTTP 429 gracefully. You must implement exponential backoff in production. The constraints object drives downstream validation.

Step 2: Construct Compensating Payloads & Schema Validation

Compensating payloads require a delivery-ref, eventbridge-matrix, and rollback-directive. The service validates these against eventbridge-constraints before execution.

package main

import (
	"crypto/sha256"
	"encoding/hex"
	"encoding/json"
	"fmt"
)

type DeliveryRef struct {
	ConversationID string `json:"conversation_id"`
	EventTimestamp string `json:"event_timestamp"`
	SequenceNumber int64  `json:"sequence_number"`
}

type RollbackDirective struct {
	Action      string                 `json:"action"`
	StateBefore map[string]interface{} `json:"state_before"`
	TargetSystem string               `json:"target_system"`
}

type CompensatingPayload struct {
	DeliveryRef       DeliveryRef       `json:"delivery_ref"`
	EventBridgeMatrix map[string]string `json:"eventbridge_matrix"`
	RollbackDirective RollbackDirective `json:"rollback_directive"`
	IdempotencyHash   string            `json:"idempotency_hash"`
	RetryCount        int               `json:"retry_count"`
}

func CalculateIdempotencyHash(payload CompensatingPayload) string {
	data, _ := json.Marshal(payload)
	hash := sha256.Sum256(data)
	return hex.EncodeToString(hash[:])
}

func ValidateCompensatingSchema(payload CompensatingPayload, constraints *EventBridgeConstraints) error {
	if payload.RetryCount > constraints.MaximumCompensationRetryCount {
		return fmt.Errorf("retry count %d exceeds maximum limit %d", payload.RetryCount, constraints.MaximumCompensationRetryCount)
	}

	if !constraints.EnableRollbackDirective && payload.RollbackDirective.Action != "" {
		return fmt.Errorf("rollback directive disabled by constraints")
	}

	found := false
	for _, allowed := range constraints.AllowedEventTypes {
		if payload.EventBridgeMatrix["event_type"] == allowed {
			found = true
			break
		}
	}
	if !found {
		return fmt.Errorf("event type %s not in eventbridge-matrix allowlist", payload.EventBridgeMatrix["event_type"])
	}

	return nil
}

The idempotency_hash prevents duplicate compensation execution during scaling events. The schema validation enforces eventbridge-constraints before any state reversal occurs.

Step 3: State-Reversal Evaluation & Atomic HTTP POST Compensation

State reversal requires verifying the target state exists, checking for partial commits, and executing an atomic HTTP POST. This step implements the non-existent-state check and partial-commit verification pipeline.

package main

import (
	"bytes"
	"context"
	"crypto/tls"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"time"
)

type CompensationResult struct {
	Success    bool
	Latency    time.Duration
	RetryCount int
	Error      error
}

func EvaluateStateReversal(ctx context.Context, payload CompensatingPayload, targetURL string) (*CompensationResult, error) {
	startTime := time.Now()

	// Non-existent-state checking
	exists, err := checkStateExists(ctx, payload.DeliveryRef.ConversationID, targetURL)
	if err != nil {
		return nil, fmt.Errorf("state existence check failed: %w", err)
	}
	if !exists {
		return &CompensationResult{
			Success: false,
			Latency: time.Since(startTime),
			Error:   fmt.Errorf("target state does not exist. skipping compensation"),
		}, nil
	}

	// Partial-commit verification
	isPartial, err := verifyPartialCommit(ctx, payload.DeliveryRef.ConversationID, targetURL)
	if err != nil {
		return nil, fmt.Errorf("partial-commit verification failed: %w", err)
	}
	if isPartial {
		return &CompensationResult{
			Success: false,
			Latency: time.Since(startTime),
			Error:   fmt.Errorf("partial commit detected. deferring compensation to transaction boundary"),
		}, nil
	}

	// Atomic HTTP POST compensation
	body, _ := json.Marshal(payload)
	req, err := http.NewRequestWithContext(ctx, http.MethodPost, targetURL, bytes.NewBuffer(body))
	if err != nil {
		return nil, fmt.Errorf("request creation failed: %w", err)
	}
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("Idempotency-Key", payload.IdempotencyHash)
	req.Header.Set("X-Compensation-Delivery-Ref", payload.DeliveryRef.ConversationID)

	httpClient := &http.Client{
		Timeout: 15 * time.Second,
		Transport: &http.Transport{
			TLSClientConfig: &tls.Config{MinVersion: tls.VersionTLS12},
		},
	}

	resp, err := httpClient.Do(req)
	if err != nil {
		return nil, fmt.Errorf("compensation request failed: %w", err)
	}
	defer resp.Body.Close()

	respBody, _ := io.ReadAll(resp.Body)

	if resp.StatusCode == http.StatusAccepted || resp.StatusCode == http.StatusOK {
		return &CompensationResult{
			Success:    true,
			Latency:    time.Since(startTime),
			RetryCount: payload.RetryCount,
		}, nil
	}

	if resp.StatusCode == http.StatusTooManyRequests {
		time.Sleep(2 * time.Second)
		return EvaluateStateReversal(ctx, payload, targetURL)
	}

	return &CompensationResult{
		Success: false,
		Latency: time.Since(startTime),
		Error:   fmt.Errorf("compensation failed with status %d: %s", resp.StatusCode, string(respBody)),
	}, nil
}

func checkStateExists(ctx context.Context, conversationID string, baseURL string) (bool, error) {
	// Simulated state check. Replace with actual downstream API call.
	req, _ := http.NewRequestWithContext(ctx, http.MethodHead, fmt.Sprintf("%s/state/%s", baseURL, conversationID), nil)
	client := &http.Client{Timeout: 5 * time.Second}
	resp, err := client.Do(req)
	if err != nil {
		return false, err
	}
	defer resp.Body.Close()
	return resp.StatusCode == http.StatusOK, nil
}

func verifyPartialCommit(ctx context.Context, conversationID string, baseURL string) (bool, error) {
	// Simulated partial-commit check. Returns true if transaction is mid-flight.
	return false, nil
}

The atomic POST includes the Idempotency-Key header. The server must return 200 or 202 for success. HTTP 429 triggers automatic retry. The state checks prevent compensation against missing or in-flight data.

Step 4: Dead-Letter Queue Sync, Metrics, & Audit Logging

Failed compensations beyond the retry limit synchronize to an external dead-letter queue. The service tracks latency, success rates, and generates governance audit logs.

package main

import (
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"time"

	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/client_golang/prometheus/promauto"
)

var (
	compensationLatency = promauto.NewHistogramVec(prometheus.HistogramOpts{
		Name: "genesys_eventbridge_compensation_latency_seconds",
		Help: "Latency of compensating transactions",
	}, []string{"event_type", "result"})

	compensationSuccessRate = promauto.NewCounterVec(prometheus.CounterOpts{
		Name: "genesys_eventbridge_compensation_total",
		Help: "Total compensation attempts and successes",
	}, []string{"result"})
)

func SyncDeadLetterQueue(payload CompensatingPayload, err error) error {
	dlqPayload := map[string]interface{}{
		"original_payload": payload,
		"failure_reason":   err.Error(),
		"timestamp":        time.Now().UTC().Format(time.RFC3339),
		"audit_ref":        payload.IdempotencyHash,
	}

	body, _ := json.Marshal(dlqPayload)
	resp, err := http.Post("https://dlq.example.com/ingest", "application/json", bytes.NewBuffer(body))
	if err != nil || resp.StatusCode >= 400 {
		return fmt.Errorf("dlq sync failed: %w", err)
	}
	return nil
}

func RecordAuditLog(payload CompensatingPayload, result *CompensationResult) {
	auditEntry := map[string]interface{}{
		"delivery_ref":      payload.DeliveryRef,
		"idempotency_hash":  payload.IdempotencyHash,
		"retry_count":       result.RetryCount,
		"latency_ms":        result.Latency.Milliseconds(),
		"success":           result.Success,
		"rollback_action":   payload.RollbackDirective.Action,
		"timestamp":         time.Now().UTC().Format(time.RFC3339),
	}

	log.Printf("AUDIT: %s", string(mustMarshalJSON(auditEntry)))

	compensationLatency.WithLabelValues(payload.EventBridgeMatrix["event_type"], fmt.Sprintf("%t", result.Success)).Observe(result.Latency.Seconds())
	compensationSuccessRate.WithLabelValues(fmt.Sprintf("%t", result.Success)).Inc()
}

func mustMarshalJSON(v interface{}) []byte {
	b, _ := json.Marshal(v)
	return b
}

The metrics expose latency distributions and success counters. The audit log captures every compensation attempt for governance. The DLQ sync ensures failed payloads are preserved for manual review.

Complete Working Example

The following Go module combines authentication, validation, compensation execution, metrics, and webhook exposure. Replace placeholders with your Genesys Cloud credentials.

package main

import (
	"context"
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"time"

	"github.com/genesyscloud/go"
	"github.com/prometheus/client_golang/prometheus/promhttp"
	"github.com/google/uuid"
)

type CompensatorService struct {
	client       *go.PlatformClient
	constraints  *EventBridgeConstraints
	targetURL    string
	compensateCh chan CompensatingPayload
}

func NewCompensatorService(cfg AuthConfig, connectionID string, targetURL string) (*CompensatorService, error) {
	client, err := NewGenesysClient(cfg)
	if err != nil {
		return nil, err
	}

	_, constraints, err := ValidateConnection(context.Background(), client, connectionID)
	if err != nil {
		return nil, err
	}

	return &CompensatorService{
		client:       client,
		constraints:  constraints,
		targetURL:    targetURL,
		compensateCh: make(chan CompensatingPayload, 100),
	}, nil
}

func (s *CompensatorService) HandleEventBridgeWebhook(w http.ResponseWriter, r *http.Request) {
	var event map[string]interface{}
	if err := json.NewDecoder(r.Body).Decode(&event); err != nil {
		http.Error(w, "invalid payload", http.StatusBadRequest)
		return
	}

	deliveryRef := DeliveryRef{
		ConversationID: fmt.Sprintf("%v", event["conversationId"]),
		EventTimestamp: fmt.Sprintf("%v", event["timestamp"]),
		SequenceNumber: int64(event["sequence"].(float64)),
	}

	matrix := map[string]string{
		"event_type": fmt.Sprintf("%v", event["eventType"]),
		"stream_id":  fmt.Sprintf("%v", event["streamId"]),
	}

	payload := CompensatingPayload{
		DeliveryRef:       deliveryRef,
		EventBridgeMatrix: matrix,
		RollbackDirective: RollbackDirective{
			Action:       "undo_state_change",
			StateBefore:  map[string]interface{}{"status": "pending"},
			TargetSystem: "external-crm",
		},
		IdempotencyHash: uuid.New().String(),
		RetryCount:      0,
	}

	payload.IdempotencyHash = CalculateIdempotencyHash(payload)

	if err := ValidateCompensatingSchema(payload, s.constraints); err != nil {
		http.Error(w, fmt.Sprintf("validation failed: %v", err), http.StatusUnprocessableEntity)
		return
	}

	s.compensateCh <- payload
	w.WriteHeader(http.StatusAccepted)
}

func (s *CompensatorService) RunCompensationWorker(ctx context.Context) {
	for payload := range s.compensateCh {
		result, err := EvaluateStateReversal(ctx, payload, s.targetURL)
		if err != nil {
			log.Printf("compensation worker error: %v", err)
			continue
		}

		RecordAuditLog(payload, result)

		if !result.Success {
			payload.RetryCount++
			if payload.RetryCount <= s.constraints.MaximumCompensationRetryCount {
				time.Sleep(time.Duration(payload.RetryCount) * 2 * time.Second)
				s.compensateCh <- payload
			} else {
				SyncDeadLetterQueue(payload, fmt.Errorf("max retries exceeded"))
			}
		}
	}
}

func main() {
	cfg := AuthConfig{
		ClientID:     "YOUR_CLIENT_ID",
		ClientSecret: "YOUR_CLIENT_SECRET",
		BaseURL:      "https://api.mypurecloud.com",
	}

	service, err := NewCompensatorService(cfg, "YOUR_CONNECTION_ID", "https://your-downstream-api.example.com/compensate")
	if err != nil {
		log.Fatalf("failed to initialize compensator: %v", err)
	}

	http.HandleFunc("/webhook", service.HandleEventBridgeWebhook)
	http.Handle("/metrics", promhttp.Handler())

	go service.RunCompensationWorker(context.Background())

	log.Println("compensator listening on :8080")
	if err := http.ListenAndServe(":8080", nil); err != nil {
		log.Fatalf("server failed: %v", err)
	}
}

This service exposes /webhook for EventBridge deliveries, processes compensation asynchronously, tracks metrics at /metrics, and syncs failures to the DLQ. The worker enforces retry limits and idempotency.

Common Errors & Debugging

Error: HTTP 401 Unauthorized

• Cause: Expired OAuth token or invalid client credentials.
• Fix: Verify the client ID and secret match the Genesys Cloud admin console. Ensure the SDK handles token refresh. Restart the service if the token cache is corrupted.
• Code Fix: The NewGenesysClient function forces an initial token fetch. If it fails, the service exits cleanly. Add a cron job to rotate credentials before expiration.

Error: HTTP 403 Forbidden

• Cause: Missing eventbridge:connection:read or eventbridge:stream:read scopes.
• Fix: Navigate to the Genesys Cloud admin console, locate the OAuth application, and add the required scopes. Reauthorize the client.
• Code Fix: The SDK returns a detailed error. Log the response body to confirm scope rejection.

Error: HTTP 429 Too Many Requests

• Cause: Exceeding Genesys Cloud API rate limits during connection validation or compensation retries.
• Fix: Implement exponential backoff. The ValidateConnection and EvaluateStateReversal functions include basic 2-second delays. Replace with time.Sleep(time.Duration(1<<retryCount) * time.Second) for production.
• Code Fix: Monitor the Retry-After header in responses. Parse it and sleep accordingly before retrying.

Error: Idempotency Collision

• Cause: Duplicate compensation requests for the same delivery-ref during scaling or webhook redelivery.
• Fix: The Idempotency-Key header and idempotency_hash field prevent duplicate execution. Ensure your downstream API stores processed hashes in a distributed cache or database.
• Code Fix: Return HTTP 200 with the original response if the hash already exists. The compensator treats this as success.

Error: Partial-Commit Verification Failure

• Cause: Downstream system reports a transaction is mid-flight. Compensating now causes data corruption.
• Fix: The worker defers compensation by requeueing the payload. Increase the retry interval for partial commits.
• Code Fix: Implement a circuit breaker pattern. If partial commits exceed a threshold, pause compensation for that target system.

Official References

• Genesys Cloud EventBridge API Documentation
• Genesys Cloud OAuth2 Client Credentials Flow
• Genesys Cloud Go SDK Repository
• Prometheus Go Client Library