fix(channels): fail fast when all channel startups fail

pkg/channels/manager.go

@@ -12,6 +12,8 @@ import (
 	"fmt"
 	"math"
 	"net/http"
+	"sort"
+	"strings"
 	"sync"
 	"time"
 
@@ -513,6 +515,7 @@ func (m *Manager) StartAll(ctx context.Context) error {
 
 	dispatchCtx, cancel := context.WithCancel(ctx)
 	m.dispatchTask = &asyncTask{cancel: cancel}
+	failedStarts := make(map[string]string)
 
 	for name, channel := range m.channels {
 		logger.InfoCF("channels", "Starting channel", map[string]any{
@@ -523,6 +526,8 @@ func (m *Manager) StartAll(ctx context.Context) error {
 				"channel": name,
 				"error":   err.Error(),
 			})
+			fmt.Printf("Failed to start channel %s: %v\n", name, err)
+			failedStarts[name] = err.Error()
 			continue
 		}
 		// Lazily create worker only after channel starts successfully
@@ -532,6 +537,32 @@ func (m *Manager) StartAll(ctx context.Context) error {
 		go m.runMediaWorker(dispatchCtx, name, w)
 	}
 
+	if len(m.channels) > 0 && len(m.workers) == 0 {
+		if m.dispatchTask != nil {
+			m.dispatchTask.cancel()
+			m.dispatchTask = nil
+		}
+
+		details := make([]string, 0, len(failedStarts))
+		for name, reason := range failedStarts {
+			details = append(details, fmt.Sprintf("%s: %s", name, reason))
+		}
+		sort.Strings(details)
+		if len(details) == 0 {
+			return fmt.Errorf("failed to start any enabled channels")
+		}
+		return fmt.Errorf("failed to start any enabled channels: %s", strings.Join(details, "; "))
+	}
+
+	if len(failedStarts) > 0 {
+		failedNames := make([]string, 0, len(failedStarts))
+		for name := range failedStarts {
+			failedNames = append(failedNames, name)
+		}
+		sort.Strings(failedNames)
+		fmt.Printf("Warning: failed to start channels: %s\n", strings.Join(failedNames, ", "))
+	}
+
 	// Start the dispatcher that reads from the bus and routes to workers
 	go m.dispatchOutbound(dispatchCtx)
 	go m.dispatchOutboundMedia(dispatchCtx)