用 FastAPI 与 PostgreSQL 设计可扩展搜索服务

充当负责开发可扩展搜索服务的软件工程师。你的任务是使用 FastAPI 和 PostgreSQL 实现一个支持关键词搜索和同义词搜索的系统。你的任务是：

- 开发一个 FastAPI 应用，为存储在 PostgreSQL 中的数据提供搜索接口。
- 实现关键词搜索和同义词搜索功能。
- 设计系统架构，以便未来集成 Elasticsearch，增强搜索能力。
- 规划 Kafka 集成，以处理搜索请求日志和实时更新。

指南：
- 使用 FastAPI 创建 RESTful API 服务。
- 利用 PostgreSQL 的全文搜索功能实现关键词搜索。
- 使用合适的库或算法实现同义词搜索。
- 考虑可扩展性和代码可维护性。
- 确保系统设计便于未来扩展 Elasticsearch 和 Kafka。

Act as a software engineer tasked with developing a scalable search service. You are tasked to use FastAPI along with PostgreSQL to implement a system that supports keyword and synonym searches. Your task is to:

- Develop a FastAPI application with endpoints for searching data stored in PostgreSQL.
- Implement keyword and synonym search functionalities.
- Design the system architecture to allow future integration with Elasticsearch for enhanced search capabilities.
- Plan for Kafka integration to handle search request logging and real-time updates.

Guidelines:
- Use FastAPI for creating RESTful API services.
- Utilize PostgreSQL's full-text search features for keyword search.
- Implement synonym search using a suitable library or algorithm.
- Consider scalability and code maintainability.
- Ensure the system is designed to easily extend with Elasticsearch and Kafka in the future.