Provide allowDelayedStart() for multi

multi/parameters.go

@@ -23,13 +23,14 @@ import (
 )
 
 type parameters struct {
-	logLevel     zerolog.Level
-	monitor      metrics.Service
-	clients      []consensusclient.Service
-	addresses    []string
-	timeout      time.Duration
-	extraHeaders map[string]string
-	enforceJSON  bool
+	logLevel          zerolog.Level
+	monitor           metrics.Service
+	clients           []consensusclient.Service
+	addresses         []string
+	timeout           time.Duration
+	extraHeaders      map[string]string
+	enforceJSON       bool
+	allowDelayedStart bool
 }
 
 // Parameter is the interface for service parameters.
@@ -85,6 +86,13 @@ func WithEnforceJSON(enforceJSON bool) Parameter {
 	})
 }
 
+// WithAllowDelayedStart allows the service to start even if the client is unavailable.
+func WithAllowDelayedStart(allowDelayedStart bool) Parameter {
+	return parameterFunc(func(p *parameters) {
+		p.allowDelayedStart = allowDelayedStart
+	})
+}
+
 // WithExtraHeaders sets additional headers to be sent with each HTTP request.
 func WithExtraHeaders(headers map[string]string) Parameter {
 	return parameterFunc(func(p *parameters) {

multi/service.go

@@ -92,8 +92,8 @@ func New(ctx context.Context, params ...Parameter) (consensusclient.Service, err
 			setProviderStateMetric(ctx, client.Address(), "inactive")
 		}
 	}
-	if len(activeClients) == 0 {
-		return nil, errors.New("no providers active, cannot proceed")
+	if len(activeClients) == 0 && !parameters.allowDelayedStart {
+		return nil, consensusclient.ErrNotActive
 	}
 	log.Trace().Int("active", len(activeClients)).Int("inactive", len(inactiveClients)).Msg("Initial providers")
 	setConnectionsMetric(ctx, len(activeClients), len(inactiveClients))

multi/service_test.go

@@ -57,7 +57,7 @@ func TestService(t *testing.T) {
 					inactiveconsensusclient,
 				}),
 			},
-			err: "no providers active, cannot proceed",
+			err: "client is not active",
 		},
 		{
 			name: "Good",