💡 Microservices: Design Pattern

Decomposition of a system
Domain-based microservices
设计模式思路
1. Domain-driven design
2. Start with the model, not the datastore
3. Evaluate (评估) actions
4. Build the service, contract first
Business process-based microservices
1. data domain, domains = microservices ?
2. leverage
3. Provide higher-level business functionality
4. Allow you to encapsulate related domains
5. No datasource access
6. Distinct(不同) functional uses
Atomic transaction-based
1. Guarantee atomicity, consistency, isolation, durability (ACID) transactions across domains
2. Provide failure domains and rollbacks
3. Force blocking until commit
4. Don’t use distributed transactions
Strangler pattern (扼杀模式)

strangling a monolith (扼杀整体式), migrate, replace
Sidecar pattern (边车模式)

Gateway pattern
1. provides a facade/proxy, can decorate, aggrregate
2. Single layer that proxies, mutates (变异), or limits calls, cors
Process aggregator(聚合器) pattern -> graphql
1. Problem: You have several business processes that must be called together and have a composite payload
2. Aggregator provides clients a single API to call
3. Can introduce its own processing logic
4. Can cause long blocking calls
5. consolidated (综合的) model
Edge pattern
1. Problem: Client use varies by platform and scaling a gateway presents wasted resources or clients need special business logic
2. Client-specific “gateways""
3. Focus on isolating calls for client systems