OAuth Token Propagation Patterns
# OAuth Token Propagation Patterns in Microservices ## 1. Token Relay Pattern ### Description Forwards the original OAuth token through service chains while maintaining the original user context. ### Implementation ```mermaid sequenceDiagram participant C as Client participant AG as API Gateway participant S1 as Service 1 participant S2 as Service 2 C->>AG: Request + OAuth Token AG->>AG: Validate Token AG->>S1: Forward Request + Token S1->>S2: Forward Request + Original Token S2->>S2: Validate Token ``` ### Considerations - **Pros:** - Simple implementation - Maintains user context - Easy to audit - **Cons:** - Token size overhead - Potential scope exposure - Limited granular control ### Code Example ```java public class TokenRelayInterceptor implements ClientHttpRequestIn...