Ambassador 模式架构

Architecture

Ambassador 模式架构图，本地代理边车处理身份验证头注入、熔断、重试逻辑和对外部第三方 API 出站请求的指标收集。该模板模拟 Ambassador 模式，与应用一起运行的辅助服务卸载外部通信的横切关注点。适合与需要弹性包装器的不可靠第三方服务集成的团队。

下载 .fz 文件

完整 FlowZap 代码

Application { # Application Container
n1: circle label:"Outbound Request"
n2: rectangle label:"Application Code"
n3: rectangle label:"Ambassador Proxy"
n4: rectangle label:"Receive Proxied Response"
n5: circle label:"End"
n1.handle(right) -> n2.handle(left)
n2.handle(right) -> n3.handle(left) [label="localhost:9000"]
n3.handle(bottom) -> AmbassadorLogic.n6.handle(top) [label="Intercept"]
n4.handle(right) -> n5.handle(left)
}
AmbassadorLogic { # Ambassador Logic
n6: rectangle label:"Add Auth Headers"
n7: rectangle label:"Apply Circuit Breaker"
n8: rectangle label:"Enable Retry Logic"
n9: rectangle label:"Collect Metrics"
n10: diamond label:"Circuit Open?"
n11: rectangle label:"Forward to External Service"
n12: rectangle label:"Return Cached Fallback"
n6.handle(right) -> n7.handle(left) [label="Bearer Token"]
n7.handle(right) -> n10.handle(left)
n10.handle(right) -> n8.handle(left) [label="Closed"]
n10.handle(bottom) -> n12.handle(top) [label="Open"]
n8.handle(right) -> n11.handle(left) [label="With Retry"]
n11.handle(bottom) -> ExternalService.n13.handle(top) [label="HTTPS"]
n12.handle(top) -> Application.n4.handle(bottom) [label="Fallback"]
n11.handle(right) -> n9.handle(left) [label="Latency"]
}
ExternalService { # External API
n13: rectangle label:"Third-Party API"
n14: rectangle label:"Process Request"
n15: rectangle label:"Return Response"
n13.handle(right) -> n14.handle(left)
n14.handle(right) -> n15.handle(left)
n15.handle(top) -> Application.n4.handle(bottom) [label="Response"]
n15.handle(top) -> AmbassadorLogic.n9.handle(bottom) [label="Metrics"]
}

为什么需要这个工作流？

Integrating with external third-party APIs often requires adding authentication headers, retry logic, circuit breaking, and metrics collection—cluttering application code with infrastructure concerns. The ambassador pattern offloads these cross-cutting concerns to a local proxy sidecar, keeping application code focused on business logic.

工作原理

Step 1: The application sends outbound requests to the ambassador proxy on localhost.
Step 2: The ambassador injects authentication headers (Bearer tokens) for the external API.
Step 3: Circuit breaker logic prevents requests to known-failing external services.
Step 4: Retry logic with exponential backoff handles transient failures automatically.
Step 5: The request is forwarded to the external third-party API over HTTPS.
Step 6: Metrics (latency, error rates) are collected for monitoring and alerting.

替代方案

Embedding resilience logic in application code creates language-specific maintenance burden. API management platforms handle some concerns but add latency. This template shows the ambassador sidecar approach for external API integration.

Key Facts

Template Name	Ambassador 模式架构
Category	Architecture
Steps	6 workflow steps
Format	FlowZap Code (.fz file)