微服务 API 网关架构

Architecture

微服务 API 网关架构图，展示请求路由、JWT 身份验证、速率限制、服务发现以及跨分布式后端服务的响应聚合。该模板模拟微服务生态系统中所有客户端流量的入口点，在请求到达内部服务之前执行安全策略。适合设计具有集中式横切关注点的可扩展 API 基础设施的平台工程师。

下载 .fz 文件

完整 FlowZap 代码

Client { # Client Application
n1: circle label:"Incoming Request"
n2: rectangle label:"Load Balancer"
n3: rectangle label:"Receive API Response"
n4: circle label:"End"
n1.handle(right) -> n2.handle(left)
n2.handle(bottom) -> Gateway.n5.handle(top) [label="Route Request"]
n3.handle(right) -> n4.handle(left)
}
Gateway { # API Gateway
n5: rectangle label:"Authenticate JWT Token"
n6: diamond label:"Token Valid?"
n7: rectangle label:"Apply Rate Limiting"
n8: rectangle label:"Return 401 Unauthorized"
n9: diamond label:"Rate Limit OK?"
n10: rectangle label:"Route to Microservice"
n11: rectangle label:"Return 429 Throttled"
n12: rectangle label:"Aggregate Responses"
n5.handle(right) -> n6.handle(left)
n6.handle(right) -> n7.handle(left) [label="Yes"]
n6.handle(bottom) -> n8.handle(top) [label="No"]
n7.handle(right) -> n9.handle(left)
n8.handle(top) -> Client.n3.handle(bottom) [label="401"]
n9.handle(right) -> n10.handle(left) [label="Yes"]
n9.handle(bottom) -> n11.handle(top) [label="No"]
n10.handle(bottom) -> Services.n13.handle(top) [label="Forward"]
n11.handle(top) -> Client.n3.handle(bottom) [label="429"]
n12.handle(top) -> Client.n3.handle(bottom) [label="Response"]
}
Services { # Microservices Cluster
n13: rectangle label:"Service Discovery Lookup"
n14: rectangle label:"User Service"
n15: rectangle label:"Order Service"
n16: rectangle label:"Inventory Service"
n17: rectangle label:"Compose Response"
n13.handle(right) -> n14.handle(left) [label="Users"]
n13.handle(bottom) -> n15.handle(top) [label="Orders"]
n14.handle(right) -> n17.handle(left)
n15.handle(right) -> n16.handle(left) [label="Check Stock"]
n16.handle(right) -> n17.handle(left)
n17.handle(top) -> Gateway.n12.handle(bottom) [label="Aggregated"]
}

为什么需要这个工作流？

Without a centralized API gateway, every microservice must independently handle authentication, rate limiting, and request routing—leading to duplicated logic, inconsistent security policies, and operational complexity. An API gateway provides a single entry point that enforces cross-cutting concerns before requests reach backend services, reducing attack surface and simplifying client integration.

工作原理

Step 1: Client sends a request through the load balancer to the API Gateway.
Step 2: The gateway validates the JWT token and checks authentication status.
Step 3: Rate limiting is applied based on client identity and configured thresholds.
Step 4: Authenticated and throttled requests are routed to the appropriate microservice via service discovery.
Step 5: Backend services process the request and return responses through the gateway for aggregation.
Step 6: The gateway composes the final response and returns it to the client.

替代方案

Building authentication and rate limiting into each service leads to inconsistency and maintenance burden. Commercial API gateways like Kong or Apigee cost $10K-100K+/year. This FlowZap template helps teams visualize their gateway architecture before implementation.

Key Facts

Template Name	微服务 API 网关架构
Category	Architecture
Steps	6 workflow steps
Format	FlowZap Code (.fz file)