I am a beginner in Spring mvc, Spring Boot and Spring Data JPA. I am trying to create Microservices using Spring Boot. I created a sample database CRUD operation as microservice in Spring Boot. Now I have A requirement that develop a microservice using Spring Cloud.
When I referring documentation seeing Spring tools for creating application in distributed environment. I am confused about why we are using Spring Cloud? And what is actually meant by Spring Cloud? Is there any relation with Spring mvc?
Spring Cloud is for developing some of the common patterns in distributed systems.
Spring Cloud provides tools for developers to quickly build some of the common patterns in distributed systems (e.g. configuration management, service discovery, circuit breakers, intelligent routing, micro-proxy, control bus, one-time tokens, global locks, leadership election, distributed sessions, cluster state)
Spring Cloud
For Spring Boot and Spring MVC, see this nice answer difference-between-spring-mvc-and-spring-boot
Related
For Spring Boot based microservices communicating with each other via load-balanced clients (with Spring Cloud LoadBalancer) which client should be used, WebClient or OpenFeign?
From what I’ve read they both support Spring Cloud LoadBalancer. I know that WebClient also supports reactive, but that is not a feature we need.
Are both clients going to continue to be supported by Spring for the foreseeable future?
From what I can see Spring seems to be pushing WebClient. However, I still see development activity going on in the spring-cloud-openfeign github repo.
OpenFeign seems to be an easier/cleaner to use way of creating the clients, but are there any drawbacks compared to WebClient?
Whats the difference between Spring Cloud Kafka Streams Vs Spring Cloud Stream Vs Spring Cloud Function Vs Spring AMQP and Spring for Apache Kafka?
Spring for Apache Kafka and Spring AMQP are foundational libraries for writing Spring friendly applications for Apache Kafka and AMQP respectively. They provide design patterns such as templates, message listener containers, and a wide array of other mechanisms to interact with the middleware systems at a lower level. These libraries do not require Spring Boot, but Spring Framework is the least common denominator. In other words, you can write a traditional Spring application with only Spring Framework contexts using these libraries.
Spring Cloud Function is a library that is part of the Spring Cloud portfolio projects. This is used as part of Spring Boot applications. It gives a consistent programming model for writing applications that involve various paradigms such as request-response (HTTP), event-driven (pub-sub), stream-processing (pub-sub/streaming), reactive streams, etc. The programming model at the application level is through the Java 8 functional model - for example you can write your business logic as a java.util.function.Function<?, ?>. Spring Cloud Function is not coupled with any middleware or other such technologies.
Spring Cloud Stream is another Spring Cloud project that is specifically built for event-driven and stream-processing usecases. Because this is a Spring Cloud project, it requires to be used as part of a Spring Boot application. The recent versions of Spring Cloud Stream is built on the foundations that Spring Cloud Function provides. This is essentially a destination binding framework that allows you to provide a destination - such as a Kafka topic or a RabbitMQ exchange. Spring Cloud Stream will bind those destinations for the application. The core Spring Cloud Stream does not have any middleware dependencies. That's where the binder implementations come in.
Spring Cloud Stream provides two kinds of Kafka binders - spring-cloud-stream-binder-kafka and spring-cloud-stream-binder-kafka-streams. The first one is a binder implementation where it provides programming model support for writing regular Kafka producers and consumers. For the most part, you can take this same application and provide another binder (such as spring-cloud-stream-binder-rabbit) and it should work (provided that the application makes the right configuration changes). This is because the binders are the ones concerned with lower-level details of communicating to the middleware and not the app itself. Apps can largely focus on the business logic at hand. The Kafka Streams binder in Spring Cloud Stream is a binder implementation specifically built for writing streaming applications using Kafka Streams. Both Kafka binder implementations use Spring for Apache Kafka under the hood.
The rabbit binder in Spring Cloud Stream uses Spring AMQP internally.
To summarize:
Spring for Apache Kafka/Spring AMQP - lower-level foundational libraries, do not require Spring Boot.
Spring Cloud Function - Spring Cloud project providing Java 8 functional programming model, Used with Spring Boot applicaitons.
Spring Cloud Stream - Framework for event-driven applications using Spring Cloud Function. Used with Spring Boot applications.
Spring Cloud Stream Kafka/Kafka Streams - Spring Cloud Stream binder implementation using Spring for Apache Kafka. Used with Spring Boot applications.
I have a question to the Spring Cloud guys.
Approx. a year ago, there were nice presentations about Spring Cloud RSocket.
Part of it included RSocket Support in Spring Cloud Gateway, aka. the rsocket-broker.
Now I see that https://github.com/spring-cloud-incubator/spring-cloud-rsocket has been archived.
I am wondering: does this mean Spring Cloud RSocket is dead? Is there any replacement? Is there any other support for RSocket in Spring Cloud Gateway? Or is Spring Cloud RSocket simply dormant and there is hope for it to be resurrected?
P.S.: I am aware of RSocket support in Spring Boot which is very nicely described here. What I am interested in, is the Spring Cloud RSocket features that I did not find the Spring Boot RSocket support.
Quoting from the description of that project
This repository is now inactive. Please see https://github.com/rsocket-broker
How do these Spring components relate/differ to/from each other? What does each represent conceptually? Would one use them together or are they competing projects?
Spring Cloud Data Flow
Spring Cloud Stream
Spring Cloud Task
Spring Cloud Task App Starters
Spring Batch
From my understanding, SC Tasks are just "units of work" to execute, a processing unit in the form of a short-lived/task-based microservice. SC Data Flow is orchestration for the tasks. These two I (think I) understand how they relate and what they represent conceptually, but a lot of documentation and examples talk about the other projects in the same context.
I also thought that SC Task was a replacement for Spring Batch but in some examples they seem to imply that Spring Batches are executed inside SC Tasks
Thanks for your interest in Spring Cloud projects! Find below the high-level introductions for the primary projects involved in Spring Cloud Data Flow (SCDF) ecosystem. The launch blog covers the backstory and among other details.
Spring Cloud Stream is a lightweight event-driven microservices framework to quickly build applications that can connect to external systems (eg: Kafka, Cassandra, MySQL, Hadoop, ..).
Spring Cloud Task is a short-lived microservices framework to quickly build applications that perform finite amounts of data processing (eg: batch-jobs, ..). The connection with Spring Batch framework is explained in the launch blog linked above.
Spring Cloud Data Flow provides the orchestration mechanics to deploy applications built with Spring Cloud Stream and Spring Cloud Task programming model to a variety of runtime platforms including Cloud Foundry, Apache Yarn, Apache Mesos and Kubernetes. There's community developed SCDF implementations for OpenShift and Nomad, too. More details here.
The building blocks visual from the project site should cover the high-level interaction between the various projects in SCDF's ecosystem.
I'm at design phase of my project and I have a doubt.
I'm modelling my system and I will use Spring Data JPA for persistence layer. Although, there is high chances of cloud deploy. Is it traumatic the portability from Spring Data JPA to Spring Clous AWS (RDS)? I didn't find direct metion about this kind of integration.
I'm trying to avoid a waste code in future.
Best Regards,
These are actually two separate things. Spring Cloud AWS JDBC will just configure a DataSource while Spring Data JPA is going to use it.
So you can use Spring Data JPA and you will be able to move your application to AWS without much efforts (basically just changing the way the DataSource is setup).