feat/login crud in users sync with sso

internal/cache/cache.go

@@ -0,0 +1,38 @@
+package cache
+
+import (
+	"errors"
+	"sync"
+
+	"github.com/redis/go-redis/v9"
+)
+
+var (
+	redisClient *redis.Client
+	mu          sync.RWMutex
+)
+
+// SetRedis assigns the global redis client used across the application.
+func SetRedis(client *redis.Client) {
+	mu.Lock()
+	defer mu.Unlock()
+	redisClient = client
+}
+
+// Redis returns the configured redis client. It may be nil if not yet initialised.
+func Redis() *redis.Client {
+	mu.RLock()
+	defer mu.RUnlock()
+	return redisClient
+}
+
+// MustRedis returns the redis client or panics if it has not been set.
+func MustRedis() *redis.Client {
+	mu.RLock()
+	client := redisClient
+	mu.RUnlock()
+	if client == nil {
+		panic(errors.New("redis client not initialised"))
+	}
+	return client
+}