feat: game lobby service

lobby/internal/adapters/streamoffsetstub/store.go

@@ -0,0 +1,56 @@
+// Package streamoffsetstub provides an in-process ports.StreamOffsetStore
+// used by worker-level tests that do not need Redis. Production code
+// never wires this stub.
+package streamoffsetstub
+
+import (
+	"context"
+	"errors"
+	"sync"
+
+	"galaxy/lobby/internal/ports"
+)
+
+// Store is a concurrency-safe in-memory ports.StreamOffsetStore.
+type Store struct {
+	mu      sync.Mutex
+	offsets map[string]string
+}
+
+// NewStore constructs an empty Store.
+func NewStore() *Store {
+	return &Store{offsets: make(map[string]string)}
+}
+
+// Load returns the last saved entry id for streamLabel.
+func (store *Store) Load(ctx context.Context, streamLabel string) (string, bool, error) {
+	if ctx == nil {
+		return "", false, errors.New("load offset: nil context")
+	}
+	store.mu.Lock()
+	defer store.mu.Unlock()
+	value, ok := store.offsets[streamLabel]
+	return value, ok, nil
+}
+
+// Save records entryID as the offset for streamLabel.
+func (store *Store) Save(ctx context.Context, streamLabel, entryID string) error {
+	if ctx == nil {
+		return errors.New("save offset: nil context")
+	}
+	store.mu.Lock()
+	defer store.mu.Unlock()
+	store.offsets[streamLabel] = entryID
+	return nil
+}
+
+// Set forces the in-memory value for streamLabel; useful in tests to
+// pre-populate state.
+func (store *Store) Set(streamLabel, entryID string) {
+	store.mu.Lock()
+	defer store.mu.Unlock()
+	store.offsets[streamLabel] = entryID
+}
+
+// Compile-time interface assertion.
+var _ ports.StreamOffsetStore = (*Store)(nil)