Andrey Meshkov f1791135af Sync v2.11.0
2024-12-05 14:19:25 +03:00

125 lines
3.1 KiB
Go

package backendpb
import (
"context"
"fmt"
"net/url"
"time"
"github.com/AdguardTeam/AdGuardDNS/internal/remotekv"
"github.com/AdguardTeam/golibs/errors"
"google.golang.org/protobuf/types/known/durationpb"
)
// RemoteKVConfig is the configuration for the business logic backend key-value
// storage.
type RemoteKVConfig struct {
// Metrics is used for the collection of the backend remote key-value
// storage statistics.
Metrics RemoteKVMetrics
// GRPCMetrics is used for the collection of the protobuf communication
// statistics.
GRPCMetrics GRPCMetrics
// Endpoint is the backend API URL. The scheme should be either "grpc" or
// "grpcs".
Endpoint *url.URL
// APIKey is the API key used for authentication, if any.
APIKey string
// TTL is the TTL of the values in the storage.
TTL time.Duration
}
// RemoteKV is the implementation of the [remotekv.Interface] interface that
// uses the business logic backend as the key-value storage. It is safe for
// concurrent use.
type RemoteKV struct {
grpcMetrics GRPCMetrics
metrics RemoteKVMetrics
client RemoteKVServiceClient
apiKey string
ttl time.Duration
}
// NewRemoteKV returns a new [RemoteKV] that retrieves information from the
// business logic backend.
func NewRemoteKV(c *RemoteKVConfig) (kv *RemoteKV, err error) {
client, err := newClient(c.Endpoint)
if err != nil {
// Don't wrap the error, because it's informative enough as is.
return nil, err
}
return &RemoteKV{
grpcMetrics: c.GRPCMetrics,
metrics: c.Metrics,
client: NewRemoteKVServiceClient(client),
apiKey: c.APIKey,
ttl: c.TTL,
}, nil
}
// type check
var _ remotekv.Interface = (*RemoteKV)(nil)
// Get implements the [remotekv.Interface] interface for *RemoteKV.
func (kv *RemoteKV) Get(ctx context.Context, key string) (val []byte, ok bool, err error) {
req := &RemoteKVGetRequest{
Key: key,
}
ctx = ctxWithAuthentication(ctx, kv.apiKey)
start := time.Now()
resp, err := kv.client.Get(ctx, req)
if err != nil {
err = fmt.Errorf("getting %q key: %w", key, fixGRPCError(ctx, kv.grpcMetrics, err))
return nil, false, err
}
kv.metrics.ObserveOperation(ctx, RemoteKVOpGet, time.Since(start))
defer func() { kv.metrics.IncrementLookups(ctx, ok) }()
received := resp.GetValue()
switch received := received.(type) {
case *RemoteKVGetResponse_Data:
return received.Data, true, nil
case *RemoteKVGetResponse_Empty:
return nil, false, nil
default:
return nil, false, fmt.Errorf(
"getting %q key: response type: %w: %T(%[3]v)",
key,
errors.ErrBadEnumValue,
received,
)
}
}
// Set implements the [remotekv.Interface] interface for *RemoteKV.
func (kv *RemoteKV) Set(ctx context.Context, key string, val []byte) (err error) {
req := &RemoteKVSetRequest{
Key: key,
Data: val,
Ttl: durationpb.New(kv.ttl),
}
ctx = ctxWithAuthentication(ctx, kv.apiKey)
start := time.Now()
_, err = kv.client.Set(ctx, req)
if err != nil {
return fmt.Errorf("setting %q key: %w", key, fixGRPCError(ctx, kv.grpcMetrics, err))
}
kv.metrics.ObserveOperation(ctx, RemoteKVOpSet, time.Since(start))
return nil
}