package redis import ( "context" "strconv" "strings" "time" "forge.cadoles.com/cadoles/bouncer/internal/proxy/director/layer/queue" "github.com/pkg/errors" "github.com/redis/go-redis/v9" ) const ( keyPrefixQueue = "queue" ) type Adapter struct { client redis.UniversalClient txMaxRetry int } // Refresh implements queue.Adapter func (a *Adapter) Refresh(ctx context.Context, queueName string, keepAlive time.Duration) error { lastSeenKey := lastSeenKey(queueName) rankKey := rankKey(queueName) err := withTx(ctx, a.client, func(ctx context.Context, tx *redis.Tx) error { expires := time.Now().UTC().Add(-keepAlive) cmd := tx.ZRangeByScore(ctx, lastSeenKey, &redis.ZRangeBy{ Min: "0", Max: strconv.FormatInt(expires.Unix(), 10), }) members, err := cmd.Result() if err != nil { return errors.WithStack(err) } if len(members) == 0 { return nil } anyMembers := make([]any, len(members)) for i, m := range members { anyMembers[i] = m } if err := tx.ZRem(ctx, rankKey, anyMembers...).Err(); err != nil { return errors.WithStack(err) } if err := tx.ZRem(ctx, lastSeenKey, anyMembers...).Err(); err != nil { return errors.WithStack(err) } return nil }, rankKey, lastSeenKey) if err != nil { return errors.WithStack(err) } return nil } // Touch implements queue.Adapter func (a *Adapter) Touch(ctx context.Context, queueName string, sessionId string) (int64, error) { lastSeenKey := lastSeenKey(queueName) rankKey := rankKey(queueName) var rank int64 retry := a.txMaxRetry for retry > 0 { err := withTx(ctx, a.client, func(ctx context.Context, tx *redis.Tx) error { now := time.Now().UTC().Unix() err := tx.ZAddNX(ctx, rankKey, redis.Z{Score: float64(now), Member: sessionId}).Err() if err != nil { return errors.WithStack(err) } err = tx.ZAdd(ctx, lastSeenKey, redis.Z{Score: float64(now), Member: sessionId}).Err() if err != nil { return errors.WithStack(err) } val, err := tx.ZRank(ctx, rankKey, sessionId).Result() if err != nil { return errors.WithStack(err) } rank = val return nil }, rankKey, lastSeenKey) if err != nil { if errors.Is(err, redis.Nil) && retry > 0 { retry-- continue } return 0, errors.WithStack(err) } break } return rank, nil } // Status implements queue.Adapter func (a *Adapter) Status(ctx context.Context, queueName string) (*queue.Status, error) { rankKey := rankKey(queueName) status := &queue.Status{} cmd := a.client.ZCard(ctx, rankKey) if err := cmd.Err(); err != nil { return nil, errors.WithStack(err) } status.Sessions = cmd.Val() return status, nil } func NewAdapter(client redis.UniversalClient, txMaxRetry int) *Adapter { return &Adapter{ client: client, txMaxRetry: txMaxRetry, } } var _ queue.Adapter = &Adapter{} func key(parts ...string) string { return strings.Join(parts, ":") } func rankKey(queueName string) string { return key(keyPrefixQueue, queueName, "rank") } func lastSeenKey(queueName string) string { return key(keyPrefixQueue, queueName, "last_seen") } func withTx(ctx context.Context, client redis.UniversalClient, fn func(ctx context.Context, tx *redis.Tx) error, keys ...string) error { txf := func(tx *redis.Tx) error { if err := fn(ctx, tx); err != nil { return errors.WithStack(err) } return nil } err := client.Watch(ctx, txf, keys...) if err != nil { return errors.WithStack(err) } return nil }