feat(registry): add WaitForNamespace method (#253)

Author: Quentin Brosse

api/registry/v1/registry_utils.go

@@ -0,0 +1,49 @@
+package registry
+
+import (
+	"time"
+
+	"github.com/scaleway/scaleway-sdk-go/internal/async"
+	"github.com/scaleway/scaleway-sdk-go/internal/errors"
+	"github.com/scaleway/scaleway-sdk-go/scw"
+)
+
+// WaitForNamespaceRequest is used by WaitForNamespace method
+type WaitForNamespaceRequest struct {
+	NamespaceID string
+	Region      scw.Region
+	Timeout     time.Duration
+}
+
+// WaitForNamespace wait for the namespace to be in a "terminal state" before returning.
+// This function can be used to wait for a namespace to be ready for example.
+func (s *API) WaitForNamespace(req *WaitForNamespaceRequest) (*Namespace, scw.SdkError) {
+	terminalStatus := map[NamespaceStatus]struct{}{
+		NamespaceStatusReady:   {},
+		NamespaceStatusLocked:  {},
+		NamespaceStatusError:   {},
+		NamespaceStatusUnknown: {},
+	}
+
+	namespace, err := async.WaitSync(&async.WaitSyncConfig{
+		Get: func() (interface{}, error, bool) {
+			ns, err := s.GetNamespace(&GetNamespaceRequest{
+				Region:      req.Region,
+				NamespaceID: req.NamespaceID,
+			})
+			if err != nil {
+				return nil, err, false
+			}
+
+			_, isTerminal := terminalStatus[ns.Status]
+
+			return ns, err, isTerminal
+		},
+		Timeout:          req.Timeout,
+		IntervalStrategy: async.LinearIntervalStrategy(5 * time.Second),
+	})
+	if err != nil {
+		return nil, errors.Wrap(err, "waiting for namespace failed")
+	}
+	return namespace.(*Namespace), nil
+}