Circuit Breaker Pattern

• Used mostly when one micro service is calling more than one micro services So failure of one does not impact other.
• Resilence4j helps us to manage fault tolerance In microservices
• Circuit Breaker(fault tolerance)
• Rate Limiter(block too frequent requests)
• Number of request a service can send to another service within a specific time frame.
• Time Limiter(Set a time when calling remote operations)
• Retry Mechanism(Automatically Retry a failed remote connection)
• Bulk Head(Avoid too many concurrent requests)
• Cache(Storing of results is costly)
• Remote Operations
• Detect something is wrong.
• Take temporary steps to avoid the situation getting worse
• Deactivate “the Problem” component so that it doesn’t affect downstream components.
• Example Resilence4j
• https://github.com/gauravmatta/springmvc/blob/979735871a339bac93395b13951857b093312a09/user-api/src/main/java/com/springimplant/userapi/controllers/OrderController.java
• https://github.com/gauravmatta/springmvc/blob/979735871a339bac93395b13951857b093312a09/user-api/src/main/resources/application.properties
• Example Hystrix
• https://github.com/gauravmatta/springmvc/blob/master/courseCatalouge/src/main/java/com/springimplant/course/controller/CatalogController.java