SAGA, Compensation Transaction, Data Consistency, Circuit Breaker, Eventual Consistency

Microservices

https://www.youtube.com/watch?v=X0tjziAQfNQ

Saga
https://docs.microsoft.com/en-us/azure/architecture/reference-architectures/saga/saga

Compensating Transaction Pattern
https://docs.microsoft.com/en-us/previous-versions/msp-n-p/dn589804(v=pandp.10)
https://docs.microsoft.com/en-us/azure/architecture/patterns/compensating-transaction

Data Consistency -> https://docs.microsoft.com/en-us/previous-versions/msp-n-p/dn589800(v=pandp.10)
Strong Data Consistency vs Eventual Consistency

Circuit Breaker pattern
https://docs.microsoft.com/en-us/azure/architecture/patterns/circuit-breaker#context-and-problem
The purpose of the Circuit Breaker pattern is different than the Retry pattern.
The Retry pattern enables an application to retry an operation in the expectation that it'll succeed.
The Circuit Breaker pattern prevents an application from performing an operation that is likely to fail

Retry pattern
https://docs.microsoft.com/en-us/azure/architecture/patterns/retry

POC - Microservices - Java Spring Cloud

Microservices POC 

https://www.youtube.com/watch?v=y8IQb4ofjDo&list=PLqq-6Pq4lTTZSKAFG6aCDVDP86Qx4lNas [JavaBrains]

https://www.youtube.com/watch?v=BnknNTN8icw [DailyCodeBuffer]

https://www.youtube.com/watch?v=tuJqH3AV0e8 [Edureka]

https://www.youtube.com/watch?v=tljuDMmfJz8&t=123s [Java Techie]

https://www.youtube.com/watch?v=rlS9eH5tEnY [Tech Primers]

https://www.youtube.com/watch?v=SzbeDqBSRkc  [PlayJava]

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Zuul POC 
https://www.youtube.com/watch?v=-I-9gK8NWXY
https://www.youtube.com/watch?v=6aG0xFpeNFw

Spring Cloud
https://spring.io/projects

Spring Cloud Gateway

https://www.youtube.com/watch?v=CJQiB9ObvaM

https://spring.io/projects/spring-cloud-gateway

To run your own gateway use the spring-cloud-starter-gateway dependency.

https://spring.io/projects/spring-cloud-circuitbreaker

Hystrix - org.springframework.cloud:spring-cloud-starter-netflix-hystrix

Circuit Breaker Pattern

https://techblog.constantcontact.com/software-development/circuit-breakers-and-microservices/

Spring Boot vs Spring Cloud

https://www.educba.com/spring-cloud-vs-spring-boot/

Cloud Design Patterns

 Circuit Breaker pattern
https://docs.microsoft.com/en-us/azure/architecture/patterns/circuit-breaker

https://techblog.constantcontact.com/software-development/circuit-breakers-and-microservices/

Compensating Transaction
https://docs.microsoft.com/en-us/azure/architecture/patterns/compensating-transaction

Saga distributed transactions
https://docs.microsoft.com/en-us/azure/architecture/reference-architectures/saga/saga
https://vasters.com/archive/Sagas.html

Saga Image
https://docs.microsoft.com/en-us/azure/architecture/reference-architectures/saga/images/choreography-pattern.png

Retry pattern
https://docs.microsoft.com/en-us/azure/architecture/patterns/retry

Microservices using SpringBoot | Full Example
https://www.youtube.com/watch?v=BnknNTN8icw

API Gateway

https://www.youtube.com/watch?v=1vjOv_f9L8I

(Forward)Proxy vs Reverse Proxy
https://www.youtube.com/watch?v=AuINJdBPf8I
(Forward)Proxy vs Reverse Proxy
Requests Going Out Via Proxy  -> Forward Proxy
Requests Coming In Via Proxy  -> Reverse Proxy
Reverse Proxy - Use cases : Security, Load Balancer , Caching 
Forward Proxy - Corporate Control, Logging, Monitoring, Cached Responses

Zuul
API Gateway
Edge Microservice -> Sits at the edge of Microservice Architecture, Very close to user input.
Edge Microservice is also known as API Gateway.
"Zuul" is an implementation of API Gateway.
API Gateway - is a Facade/Abstraction Layer at the very edge of Microservices Architecture , 
which handles incoming Requests

Eureka
Eureka - "Found it" in Ancient Greek
Archimedes said it!!!
Eureka is a Registry and LookUp Service which allows Microservice to know each other

Hystrix
Fault Tolerant Library from Netflix which Implements "Circuit - Breaker" Pattern

<!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-hystrix -->
<dependency>
    <groupId>org.springframework.cloud</groupId>
    <artifactId>spring-cloud-starter-hystrix</artifactId>
    <version>1.4.7.RELEASE</version>
</dependency>

How to configure SpringCloud Zuul – Routing and Filtering using SpringBoot | Java Techie
https://www.youtube.com/watch?v=6aG0xFpeNFw