Micro service Archtecture implementation with Spring Cloud projects.

Create Spring Cloud project : How to create Spring Cloud Project?

You can either create project by Spring Initializr: by adding cloud components from Dependencies button or create Spring boot project first, and then add clound components. I prefered the second method, because in first approach, you have so many components in dependencies, as a beginner, how you know which you need to download?

So Our approach is download the spring boot project then build from there:

Create Spring Cloud Project in Intellij:

Since I am using Intellij IDEA Community Version, so I don’t have Spring Initiazr tool, and what I did is create a new Java project with Gradle, then did following:

1. open the

plugins {
	id 'org.springframework.boot' version '2.3.4.RELEASE'
	id 'io.spring.dependency-management' version '1.0.10.RELEASE'
	id 'java'
}

group = 'com.r0ngsh3n.restful'
version = '0.0.1-SNAPSHOT'
sourceCompatibility = '11'

repositories {
	mavenCentral()
}

dependencies {
	implementation 'com.h2database:h2'
	implementation 'org.springframework.boot:spring-boot-starter-data-jpa'
	implementation 'org.springframework.boot:spring-boot-starter-validation'
	implementation 'org.springframework.boot:spring-boot-starter-web'
	testImplementation('org.springframework.boot:spring-boot-starter-test') {
		exclude group: 'org.junit.vintage', module: 'junit-vintage-engine'
	}
}

test {
	useJUnitPlatform()
}

You MUST need to understand the different Spring Cloud version first, I am using Hoston version

I list 2 version I think most user friendly here. Please notice Spring Cloud Release naming is very different from other Spring projects.

Service Producer and Consumer

There are 2 roles in Microservices Archtechture: Consumer : consume service. eg: query a @Service to get user object Producer: provide service. eg: UserService provide findByUserName service(method)

Components

Spring Actuator and Micrometer

link

Zookeeper

I use Zookeeper here, it is better than Eureka, here is why.

Ribbon

Feign

Hystrix

Spring Cloue Gateway (say no to Zuul)

Spring Cloud Config

Spring Cloud Sleuth

Spring Cloud Stream

Conclusion

• Validation should leave to Model (User object in this case) object.
• There should be a center point to handle all the exception cross the board.
• The Response object should be an unified format.
• Controller Advice is solution for handle request/response cross the board, with this function, we can handle Exception and Response cross the board.