Delete Coordinator core and apis

internal/grpc/retry/retry.go

@@ -0,0 +1,63 @@
+package retry
+
+import (
+	"context"
+	"strings"
+	"time"
+
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+	"k8s.io/utils/clock"
+)
+
+type IntervalRetryer struct {
+	interval time.Duration
+	doer     Doer
+	clock    clock.WithTicker
+}
+
+func NewIntervalRetryer(doer Doer, interval time.Duration) *IntervalRetryer {
+	return &IntervalRetryer{
+		interval: interval,
+		doer:     doer,
+		clock:    clock.RealClock{},
+	}
+}
+
+func (r *IntervalRetryer) Do(ctx context.Context) error {
+	ticker := r.clock.NewTicker(r.interval)
+	defer ticker.Stop()
+
+	for {
+		err := r.doer.Do(ctx)
+		if err == nil {
+			return nil
+		}
+
+		if !r.serviceIsUnavailable(err) {
+			return err
+		}
+
+		select {
+		case <-ctx.Done(): // TODO(katexochen): is this necessary?
+			return ctx.Err()
+		case <-ticker.C():
+		}
+	}
+}
+
+func (r *IntervalRetryer) serviceIsUnavailable(err error) bool {
+	statusErr, ok := status.FromError(err)
+	if !ok {
+		return false
+	}
+	if statusErr.Code() != codes.Unavailable {
+		return false
+	}
+	// ideally we would check the error type directly, but grpc only provides a string
+	return strings.HasPrefix(statusErr.Message(), `connection error: desc = "transport: authentication handshake failed`)
+}
+
+type Doer interface {
+	Do(ctx context.Context) error
+}