How do SOLID principles apply to microservices?
Answer
SOLID scales from class design to service design in microservices. SRP at service level: each microservice should have one bounded context — an order service handles orders, a user service handles users. Services with multiple domains become distributed monoliths. OCP: services should be extensible via new endpoints or event consumers without breaking existing contracts. LSP: in API versioning, v2 of an API should remain substitutable for v1 — clients using v1 contracts should not break when upgraded. ISP: expose only the API surface that clients need; use API gateway patterns to create role-specific facades. DIP: services communicate via abstract contracts (OpenAPI specs, message schemas) rather than direct code dependencies, enabling independent deployment.
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More SOLID Principles Questions
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- Intermediate How does the Strategy pattern support OCP?
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