feat: add user request limit config (#98)

pkg/cache/user_context.go

@@ -0,0 +1,22 @@
+package cache
+
+import "github.com/patrickmn/go-cache"
+
+// SetUserSessionContext 设置用户会话上下文文本，question用户提问内容，GTP回复内容
+func (s *UserService) SetUserSessionContext(userId string, content string) {
+	s.cache.Set(userId+"_content", content, cache.DefaultExpiration)
+}
+
+// GetUserSessionContext 获取用户会话上下文文本
+func (s *UserService) GetUserSessionContext(userId string) string {
+	sessionContext, ok := s.cache.Get(userId + "_content")
+	if !ok {
+		return ""
+	}
+	return sessionContext.(string)
+}
+
+// ClearUserSessionContext 清空GTP上下文，接收文本中包含 SessionClearToken
+func (s *UserService) ClearUserSessionContext(userId string) {
+	s.cache.Delete(userId + "_content")
+}