chore: update session and challenge repo -- using Redis for caching session and challenge verifying -- added api handler docs

pkg/cache/redis.go

@@ -0,0 +1,36 @@
+package cache
+
+import (
+	"backend/config"
+	"context"
+	"fmt"
+
+	"github.com/redis/go-redis/v9"
+)
+
+type Redis struct {
+	client *redis.Client
+}
+
+func NewRedis(cfg config.Redis) (*Redis, error) {
+	rdb := redis.NewClient(&redis.Options{
+		Addr:     fmt.Sprintf("%s:%d", cfg.Host, cfg.Port),
+		Password: cfg.Pass,
+		DB:       0,
+	})
+
+	ctx := context.Background()
+	if err := rdb.Ping(ctx).Err(); err != nil {
+		return nil, fmt.Errorf("failed to connect to Redis: %w", err)
+	}
+
+	return &Redis{client: rdb}, nil
+}
+
+func (r *Redis) Client() *redis.Client {
+	return r.client
+}
+
+func (r *Redis) Close() error {
+	return r.client.Close()
+}