feat: added redis cache methods

internal/cache/redis.go

@@ -1,2 +1,71 @@
 package cache
 
+import (
+	"context"
+	"fmt"
+	"time"
+
+	"github.com/redis/go-redis/v9"
+)
+
+type Cache struct {
+	Client *redis.Client
+}
+
+// CreateCache creates a new Redis Cache
+func CreateCache(host string, port int, db int) *Cache {
+	address := fmt.Sprintf("%s:%d", host, port)
+	rdb := redis.NewClient(&redis.Options{
+		Addr:     address,
+		Password: "",
+		DB:       db,
+	})
+
+	return &Cache{
+		Client: rdb,
+	}
+}
+
+// Set sets a key value in the cache with an expiry
+func (c *Cache) Set(ctx context.Context, key string, value any, expiration time.Duration) error {
+	return c.Client.Set(ctx, key, value, expiration).Err()
+}
+
+// Get returns a key value from the cache if there is any
+func (c *Cache) Get(ctx context.Context, key string) (string, error) {
+	return c.Client.Get(ctx, key).Result()
+}
+
+// Clear clears specific keys from the cache
+func (c *Cache) Clear(ctx context.Context, keys ...string) error {
+	return c.Client.Del(ctx, keys...).Err()
+}
+
+// ClearPattern clears keys by pattern (e.g. "user:*")
+func (c *Cache) ClearPattern(ctx context.Context, pattern string) error {
+	var cursor uint64
+	for {
+		keys, nextCursor, err := c.Client.Scan(ctx, cursor, pattern, 100).Result()
+		if err != nil {
+			return err
+		}
+
+		if len(keys) > 0 {
+			// Unlink instead of Del for large datasets because it's non-blocking
+			if err := c.Client.Unlink(ctx, keys...).Err(); err != nil {
+				return err
+			}
+		}
+
+		cursor = nextCursor
+		if cursor == 0 {
+			break
+		}
+	}
+	return nil
+}
+
+// Flush clears entire current db
+func (c *Cache) Flush(ctx context.Context) error {
+	return c.Client.FlushDB(ctx).Err()
+}