feat(caddystorage): init Caddy storage module backed by an Uncloud cluster

caddystorage/storage.go

@@ -0,0 +1,84 @@
+package caddystorage
+
+import (
+	"context"
+	"fmt"
+	"io/fs"
+
+	"github.com/caddyserver/certmagic"
+	"github.com/psviderski/uncloud/api/pb"
+	"google.golang.org/grpc/codes"
+	"google.golang.org/grpc/status"
+)
+
+// Store writes a value to the cluster store.
+func (s *Storage) Store(ctx context.Context, key string, value []byte) error {
+	if _, err := s.client.CaddyStorage.Store(ctx, &pb.StoreCaddyStorageRequest{Key: key, Value: value}); err != nil {
+		return storageError("store", key, err)
+	}
+	return nil
+}
+
+// Load reads a value from the cluster store.
+func (s *Storage) Load(ctx context.Context, key string) ([]byte, error) {
+	resp, err := s.client.CaddyStorage.Load(ctx, &pb.LoadCaddyStorageRequest{Key: key})
+	if err != nil {
+		return nil, storageError("load", key, err)
+	}
+	return resp.Value, nil
+}
+
+// Delete removes a key and its descendants from the cluster store.
+func (s *Storage) Delete(ctx context.Context, key string) error {
+	if _, err := s.client.CaddyStorage.Delete(ctx, &pb.DeleteCaddyStorageRequest{Key: key}); err != nil {
+		return storageError("delete", key, err)
+	}
+	return nil
+}
+
+// Exists reports whether a key exists in the cluster store.
+func (s *Storage) Exists(ctx context.Context, key string) bool {
+	_, err := s.Stat(ctx, key)
+	return err == nil
+}
+
+// List returns keys under prefix from the cluster store.
+func (s *Storage) List(ctx context.Context, prefix string, recursive bool) ([]string, error) {
+	resp, err := s.client.CaddyStorage.List(ctx, &pb.ListCaddyStorageRequest{
+		Prefix:    prefix,
+		Recursive: recursive,
+	})
+	if err != nil {
+		return nil, storageError("list", prefix, err)
+	}
+	return resp.Keys, nil
+}
+
+// Stat returns information about a key in the cluster store.
+func (s *Storage) Stat(ctx context.Context, key string) (certmagic.KeyInfo, error) {
+	resp, err := s.client.CaddyStorage.Stat(ctx, &pb.StatCaddyStorageRequest{Key: key})
+	if err != nil {
+		return certmagic.KeyInfo{}, storageError("stat", key, err)
+	}
+
+	info := certmagic.KeyInfo{
+		Key:        resp.Key,
+		Size:       resp.Size,
+		IsTerminal: resp.IsTerminal,
+	}
+	if resp.UpdatedAt != nil {
+		if err := resp.UpdatedAt.CheckValid(); err != nil {
+			return certmagic.KeyInfo{}, storageError("stat", key, fmt.Errorf("invalid updated_at timestamp: %w", err))
+		}
+		info.Modified = resp.UpdatedAt.AsTime()
+	}
+	return info, nil
+}
+
+func storageError(operation, key string, err error) error {
+	if status.Code(err) == codes.NotFound {
+		err = fs.ErrNotExist
+	}
+	// TODO: figure out what the appropriate way of calling the storage in caddy logs is, e.g. include uncloud or redundant if logger includes the name?
+	return fmt.Errorf("%s Caddy storage key '%s': %w", operation, key, err)
+}