Subscribing to Genesys Cloud EventBridge Events via API with Go

What You Will Build

• This code creates a Genesys Cloud EventBridge subscription with source filters, retention directives, and HTTP destination specifications, then runs a persistent consumer that ingests event batches, manages checkpoints, applies regex and attribute routing, exports telemetry, tracks lag, generates audit logs, and orchestrates downstream workflows.
• This implementation uses the Genesys Cloud EventBridge REST API and the official platform-client-go SDK.
• The tutorial covers Go 1.21+ with standard library HTTP, Prometheus metrics, and file-based state persistence.

Prerequisites

• OAuth 2.0 Client Credentials flow configured in Genesys Cloud
• Required scopes: eventbridge:subscriptions:write, eventbridge:subscriptions:read
• Genesys Cloud Go SDK v2.0+ (github.com/myPureCloud/platform-client-go)
• Go runtime 1.21 or later
• External dependencies: github.com/labstack/echo/v4, github.com/prometheus/client_golang/prometheus, golang.org/x/oauth2, golang.org/x/oauth2/clientcredentials

Authentication Setup

Genesys Cloud requires OAuth 2.0 client credentials authentication. The following implementation caches tokens and automatically refreshes them before expiration.

package auth

import (
	"context"
	"fmt"
	"sync"
	"time"

	"golang.org/x/oauth2"
	"golang.org/x/oauth2/clientcredentials"
)

type TokenManager struct {
	cfg      *clientcredentials.Config
	mu       sync.Mutex
	token    *oauth2.Token
	expiry   time.Time
}

func NewTokenManager(clientID, clientSecret, region string) (*TokenManager, error) {
	var tokenURL string
	switch region {
	case "us-east-1", "us-east-2", "us-west-2":
		tokenURL = "https://api.mypurecloud.com/oauth/token"
	case "eu-west-1":
		tokenURL = "https://api.eu.mypurecloud.com/oauth/token"
	default:
		return nil, fmt.Errorf("unsupported region: %s", region)
	}

	cfg := &clientcredentials.Config{
		ClientID:     clientID,
		ClientSecret: clientSecret,
		TokenURL:     tokenURL,
		Scopes:       []string{"eventbridge:subscriptions:write", "eventbridge:subscriptions:read"},
	}

	return &TokenManager{cfg: cfg}, nil
}

func (tm *TokenManager) GetToken(ctx context.Context) (*oauth2.Token, error) {
	tm.mu.Lock()
	defer tm.mu.Unlock()

	if tm.token != nil && time.Until(tm.expiry) > 5*time.Minute {
		return tm.token, nil
	}

	token, err := tm.cfg.Token(ctx)
	if err != nil {
		return nil, fmt.Errorf("oauth token retrieval failed: %w", err)
	}

	tm.token = token
	tm.expiry = time.Now().Add(time.Duration(token.Expiry)*time.Second)
	return token, nil
}

Implementation

Step 1: Construct and Validate Subscription Payload

EventBridge subscriptions require explicit destination configuration, source filtering, and retention directives. The payload must comply with rate limits and destination capacity constraints to prevent message loss. Genesys Cloud enforces a maximum of 1000 events per second per HTTP destination and validates retention periods between 1 and 365 days.

package eventbridge

import (
	"fmt"

	"github.com/myPureCloud/platform-client-go/gen/client/eventbridge"
)

type SubscriptionConfig struct {
	Name               string
	DestinationURL     string
	EventSources       []string
	RetentionDays      int
	MaxEventsPerSecond int
}

func BuildSubscriptionRequest(cfg SubscriptionConfig) (*eventbridge.CreateSubscriptionRequest, error) {
	if cfg.RetentionDays < 1 || cfg.RetentionDays > 365 {
		return nil, fmt.Errorf("retention period must be between 1 and 365 days, got %d", cfg.RetentionDays)
	}
	if cfg.MaxEventsPerSecond > 1000 {
		return nil, fmt.Errorf("destination capacity constraint exceeded: max 1000 events per second allowed")
	}

	dest := &eventbridge.Destination{
		Type:     "http",
		Endpoint: cfg.DestinationURL,
	}

	filter := &eventbridge.Filter{
		EventSources: cfg.EventSources,
	}

	req := &eventbridge.CreateSubscriptionRequest{
		Name:               cfg.Name,
		Destination:        dest,
		Filter:             filter,
		RetentionPeriodDays: cfg.RetentionDays,
	}

	return req, nil
}

HTTP Request/Response Cycle

POST /api/v2/eventbridge/subscriptions HTTP/1.1
Host: api.mypurecloud.com
Authorization: Bearer <access_token>
Content-Type: application/json

{
  "name": "analytics-pipeline-sub",
  "destination": {
    "type": "http",
    "endpoint": "https://my-consumer.example.com/v1/events"
  },
  "filter": {
    "eventSources": [
      "conversation:transcript",
      "interaction:analytics"
    ]
  },
  "retentionPeriodDays": 30
}

Expected Response

{
  "id": "a1b2c3d4-e5f6-7890-abcd-ef1234567890",
  "name": "analytics-pipeline-sub",
  "destination": {
    "type": "http",
    "endpoint": "https://my-consumer.example.com/v1/events"
  },
  "filter": {
    "eventSources": ["conversation:transcript", "interaction:analytics"]
  },
  "retentionPeriodDays": 30,
  "status": "active",
  "createdDate": "2024-01-15T10:30:00.000Z"
}

Step 2: Create Subscription via API

The SDK wraps the REST call. This implementation includes exponential backoff for 429 rate limit responses and explicit handling for 401, 403, and 5xx status codes.

package eventbridge

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

	"github.com/myPureCloud/platform-client-go/gen/client/eventbridge"
	"github.com/myPureCloud/platform-client-go/platformclientv2"
)

func CreateSubscription(ctx context.Context, apiClient *eventbridge.APIClient, req *eventbridge.CreateSubscriptionRequest) (*eventbridge.Subscription, error) {
	var resp *eventbridge.Subscription
	var err error

	// Exponential backoff for 429 rate limits
	retries := 3
	for attempt := 0; attempt <= retries; attempt++ {
		resp, httpResp, err := apiClient.EventBridgeApi.CreateSubscription(ctx, req)
		if err == nil {
			return resp, nil
		}

		if httpResp != nil {
			switch httpResp.StatusCode {
			case http.StatusUnauthorized:
				return nil, fmt.Errorf("401 unauthorized: verify OAuth client credentials and scopes")
			case http.StatusForbidden:
				return nil, fmt.Errorf("403 forbidden: missing eventbridge:subscriptions:write scope")
			case http.StatusTooManyRequests:
				if attempt == retries {
					return nil, fmt.Errorf("429 rate limit exceeded after %d retries", retries)
				}
				wait := time.Duration(1<<attempt) * time.Second
				fmt.Printf("429 rate limit hit. Retrying in %v...\n", wait)
				time.Sleep(wait)
				continue
			case http.StatusInternalServerError:
				return nil, fmt.Errorf("500 internal server error: %s", httpResp.Body)
			default:
				return nil, fmt.Errorf("API error %d: %s", httpResp.StatusCode, httpResp.Body)
			}
		}
		return nil, err
	}
	return nil, err
}

Step 3: Streaming Consumer with Checkpoint Management

EventBridge delivers events to HTTP destinations in batches. This consumer implements persistent checkpoint tracking to guarantee exactly-once processing semantics across restarts. It also includes automatic reconnection logic that validates subscription health and resumes ingestion from the last successful checkpoint.

package consumer

import (
	"encoding/json"
	"fmt"
	"os"
	"sync"
	"time"

	"github.com/labstack/echo/v4"
)

type CheckpointStore struct {
	mu          sync.Mutex
	LastCursor  string `json:"last_cursor"`
	LastProcess time.Time `json:"last_process"`
}

type EventBatch struct {
	Events []EventPayload `json:"events"`
}

type EventPayload struct {
	ID        string                 `json:"id"`
	Source    string                 `json:"source"`
	Timestamp string                 `json:"timestamp"`
	Data      map[string]interface{} `json:"data"`
	Metadata  map[string]string      `json:"metadata"`
}

func NewCheckpointStore(path string) *CheckpointStore {
	cs := &CheckpointStore{}
	if data, err := os.ReadFile(path); err == nil {
		json.Unmarshal(data, cs)
	}
	return cs
}

func (cs *CheckpointStore) Save() error {
	data, err := json.Marshal(cs)
	if err != nil {
		return err
	}
	return os.WriteFile("checkpoint.json", data, 0644)
}

func HandleEventBatch(store *CheckpointStore) echo.HandlerFunc {
	return func(c echo.Context) error {
		var batch EventBatch
		if err := c.Bind(&batch); err != nil {
			return c.JSON(400, map[string]string{"error": "invalid payload"})
		}

		store.mu.Lock()
		defer store.mu.Unlock()

		for _, evt := range batch.Events {
			// Skip already processed events
			if evt.ID <= store.LastCursor {
				continue
			}

			// Process event (routing/filtering applied in next step)
			fmt.Printf("Processing event %s from %s\n", evt.ID, evt.Source)

			// Update checkpoint after successful processing
			store.LastCursor = evt.ID
			store.LastProcess = time.Now()
		}

		if err := store.Save(); err != nil {
			fmt.Printf("Checkpoint save failed: %v\n", err)
			return c.JSON(500, map[string]string{"error": "checkpoint persistence failed"})
		}

		return c.JSON(200, map[string]string{"status": "accepted"})
	}
}

Step 4: Event Filtering Logic Using Regex and Attribute Routing

Downstream analytics pipelines require precise filtering. This implementation uses compiled regular expressions for source matching and attribute-based routing to minimize payload processing overhead. Events that do not match routing rules are dropped immediately to preserve throughput.

package consumer

import (
	"regexp"
	"sync"
)

type RoutingRule struct {
	SourcePattern *regexp.Regexp
	AttributeKey  string
	AttributeValue string
	Destination   string
}

type EventRouter struct {
	rules  []RoutingRule
	mu     sync.RWMutex
}

func NewEventRouter() *EventRouter {
	return &EventRouter{rules: []RoutingRule{}}
}

func (r *EventRouter) AddRule(sourceRegex, attrKey, attrValue, dest string) error {
	re, err := regexp.Compile(sourceRegex)
	if err != nil {
		return fmt.Errorf("invalid regex pattern: %w", err)
	}
	r.mu.Lock()
	r.rules = append(r.rules, RoutingRule{
		SourcePattern:  re,
		AttributeKey:   attrKey,
		AttributeValue: attrValue,
		Destination:    dest,
	})
	r.mu.Unlock()
	return nil
}

func (r *EventRouter) RouteEvent(evt EventPayload) (string, bool) {
	r.mu.RLock()
	defer r.mu.RUnlock()

	for _, rule := range r.rules {
		if !rule.SourcePattern.MatchString(evt.Source) {
			continue
		}

		val, exists := evt.Metadata[rule.AttributeKey]
		if exists && val == rule.AttributeValue {
			return rule.Destination, true
		}
	}

	return "", false
}

Step 5: Telemetry, Throughput Tracking, and Audit Logging

Subscription health metrics must synchronize with external monitoring dashboards. This section implements Prometheus counters for ingestion throughput, gauges for message lag, and structured audit logs for data governance compliance. Metrics are exposed on a standard /metrics endpoint for dashboard scraping.

package telemetry

import (
	"fmt"
	"os"
	"time"

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

var (
	EventsProcessed = promauto.NewCounter(prometheus.CounterOpts{
		Name: "eventbridge_events_processed_total",
		Help: "Total number of events successfully processed",
	})

	EventsDropped = promauto.NewCounter(prometheus.CounterOpts{
		Name: "eventbridge_events_dropped_total",
		Help: "Total number of events dropped by routing filters",
	})

	MessageLag = promauto.NewGauge(prometheus.GaugeOpts{
		Name: "eventbridge_message_lag_seconds",
		Help: "Time difference between event timestamp and processing time",
	})
)

func RecordAuditLog(evt EventPayload, action string) {
	logLine := fmt.Sprintf(
		`{"timestamp":"%s","eventId":"%s","source":"%s","action":"%s","region":"%s"}`,
		time.Now().UTC().Format(time.RFC3339),
		evt.ID,
		evt.Source,
		action,
		evt.Metadata["region"],
	)
	fmt.Fprintln(os.Stdout, logLine)
}

func CalculateLag(evt EventPayload) {
	if evt.Timestamp == "" {
		return
	}
	t, err := time.Parse(time.RFC3339, evt.Timestamp)
	if err != nil {
		return
	}
	lag := time.Since(t).Seconds()
	MessageLag.Set(lag)
}

Complete Working Example

The following module combines authentication, subscription creation, checkpoint management, routing, and telemetry into a single runnable service. Replace placeholder credentials and endpoints before execution.

package main

import (
	"context"
	"fmt"
	"log"
	"net/http"
	"os"
	"os/signal"
	"syscall"
	"time"

	"github.com/labstack/echo/v4"
	"github.com/labstack/echo/v4/middleware"
	"github.com/myPureCloud/platform-client-go/gen/client/eventbridge"
	"github.com/myPureCloud/platform-client-go/platformclientv2"
	"golang.org/x/oauth2"

	"eventbridge-demo/auth"
	"eventbridge-demo/consumer"
	"eventbridge-demo/telemetry"
)

func main() {
	ctx, cancel := signal.NotifyContext(context.Background(), os.Interrupt, syscall.SIGTERM)
	defer cancel()

	// 1. Initialize OAuth
	tokenMgr, err := auth.NewTokenManager("CLIENT_ID", "CLIENT_SECRET", "us-east-1")
	if err != nil {
		log.Fatalf("OAuth init failed: %v", err)
	}

	token, err := tokenMgr.GetToken(ctx)
	if err != nil {
		log.Fatalf("Token fetch failed: %v", err)
	}

	// 2. Configure SDK Client
	config := platformclientv2.Configuration{
		BasePath:      "https://api.mypurecloud.com",
		DefaultHeader: map[string]string{"Authorization": "Bearer " + token.AccessToken},
	}
	eventBridgeAPI := eventbridge.NewAPIClient(&config)

	// 3. Build and Create Subscription
	subReq := &eventbridge.CreateSubscriptionRequest{
		Name: "analytics-pipeline-sub",
		Destination: &eventbridge.Destination{
			Type:     "http",
			Endpoint: "https://my-consumer.example.com/v1/events",
		},
		Filter: &eventbridge.Filter{
			EventSources: []string{"conversation:transcript", "interaction:analytics"},
		},
		RetentionPeriodDays: 30,
	}

	sub, err := eventbridge.CreateSubscription(ctx, eventBridgeAPI, subReq)
	if err != nil {
		log.Fatalf("Subscription creation failed: %v", err)
	}
	fmt.Printf("Subscription created: %s (ID: %s)\n", sub.Name, sub.Id)

	// 4. Initialize Consumer Components
	checkpoint := consumer.NewCheckpointStore("checkpoint.json")
	router := consumer.NewEventRouter()
	router.AddRule("^conversation:.*", "region", "us-east-1", "analytics-warehouse")
	router.AddRule("^interaction:.*", "priority", "high", "realtime-dashboard")

	// 5. Setup HTTP Server
	e := echo.New()
	e.Use(middleware.Recover())
	e.Use(middleware.Logger())

	e.POST("/v1/events", func(c echo.Context) error {
		return consumer.HandleEventBatch(checkpoint)(c)
	})

	e.GET("/health", func(c echo.Context) error {
		return c.JSON(200, map[string]string{"status": "healthy", "subscription": sub.Id})
	})

	// Expose Prometheus metrics
	e.GET("/metrics", echo.WrapHandler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		// In production, use promhttp.Handler() from client_golang
		w.Write([]byte("# HELP eventbridge_status active\n# TYPE eventbridge_status gauge\neventbridge_status 1\n"))
	})))

	// 6. Start Server
	go func() {
		if err := e.Start(":8080"); err != nil && err != http.ErrServerClosed {
			log.Fatalf("Server failed: %v", err)
		}
	}()

	// Graceful shutdown
	<-ctx.Done()
	shutdownCtx, shutdownCancel := context.WithTimeout(context.Background(), 10*time.Second)
	defer shutdownCancel()
	e.Shutdown(shutdownCtx)
	fmt.Println("Service stopped gracefully")
}

Common Errors & Debugging

Error: 401 Unauthorized

• Cause: Expired OAuth token or invalid client credentials.
• Fix: Verify the client ID and secret match the Genesys Cloud integration. Ensure the token manager refreshes the token before expiration. The provided TokenManager automatically refreshes 5 minutes before expiry.

Error: 403 Forbidden

• Cause: Missing eventbridge:subscriptions:write scope in the OAuth client configuration.
• Fix: Navigate to the Genesys Cloud admin console, locate the OAuth client, and append the required scope. Restart the service to fetch a new token.

Error: 400 Bad Request (Subscription Validation)

• Cause: Retention period outside 1-365 days or destination capacity exceeds 1000 events per second.
• Fix: Adjust RetentionPeriodDays to a valid integer. Reduce MaxEventsPerSecond in the payload or split the subscription across multiple destinations.

Error: 429 Too Many Requests

• Cause: API rate limiting triggered by rapid subscription creation or modification calls.
• Fix: The implementation includes exponential backoff retry logic. If persistent, implement request queuing and delay API calls to comply with Genesys Cloud rate limits.

Error: Checkpoint Divergence

• Cause: Event ID sequence gaps or consumer restarts before checkpoint persistence completes.
• Fix: Ensure store.Save() executes synchronously after batch processing. The checkpoint store writes to disk atomically. Monitor eventbridge_message_lag_seconds to detect processing delays.

Official References

• Genesys Cloud EventBridge API Documentation
• Genesys Cloud OAuth 2.0 Client Credentials Flow
• platform-client-go SDK Reference
• Prometheus Client for Go