Do we need to use anyone framework like eventuate, camunda, etc. for implementing Orchestration-based SAGA microservices in spring boot?
You can use eventuate framework to setup a Orchestration-based Saga.
You will need to add Orchestra-tor dependency to your orchestra-tor, and participant dependencies to all the participant micro-services.
You will also need to run Eventuate CDC tram service, which enables the Transctional messaging services along with the DB.
Try this link and join the slack channel, Mr Cris himself will answer to your issues. Mostly in few hours or a day.
https://github.com/eventuate-tram/eventuate-tram-sagas-examples-customers-and-orders
Related
We're using a hexagonal architecture in one of our microservice. Spring Boot is the framework implementing the service.
For a use case, we need to update a database table (relational) and send a message to a Kafka topic. Quite usual. We don't want to use any CDC or Outbox Pattern, but we want to rely on the transactional manager of Spring.
However, we need some clarification about how to implement this scenario. We don't want to have any dependency on the framework in the application layer (service/use case). How can we implement transactionality? Should we use the #Transactional annotation on the controller? Should we have a single output port, for example, saveAndPublish (I don't like this solution), and put the transaction management in the implementing adapter?
I know that every use case should be transactional by design.
I am using Spring Cloud Contract, now I am making an integration test for event driven microservices.
Can i combine both Spring Cloud Contract (messaging) with Kafka container running on TestContainer? I want to use the StubTrigger of course but it should fetch the message also from my Kafka topic. Any suggestion? Does it even make sense? I think i am mixing the concepts.
Yes you can. You can check out the examples with kafka and testcontainers here https://github.com/spring-cloud-samples/spring-cloud-contract-samples/tree/main/consumer_kafka_middleware and here https://github.com/spring-cloud-samples/spring-cloud-contract-samples/tree/main/producer_kafka_middleware
I'm studying Axon framework to try to use it in one of my microservices. I use Spring boot as my microservice and I want to use Axon framewrok for DDD and event sourcing. The thing is we already use Kafka in production and I'm not sure I can add another service (Axon serve) since it might consume resources I don't have (does it consume a lot of resources by the way?)
So I was thinking to use Kafka as event source and event routing with Axon.
Is it possible?
You can use Kafka as event bus using the Kafka extension for Axon. You can't use Kafka as event store however. So you still need Axon Server or a relational database for the event store to use Axon Framework.
You could also combine those, e.g. have some events via Kafka, and some via Axon Server.
I'm looking for the azure alternative for the Data flow model of Data Source-processor-sink.
I want the three entities to be separate microservices. I want to use messaging as a link between these three.
Basically, Source app takes the data from another service and sends it to processor while processor app acts on it and sends relevant notification/alert to sink.
I'm aware I can use rabbitmq for the messaging but I need to know which one will be better in azure - service bus topics or eventhub? and how can I use them?
At the moment, there isn't a Spring Cloud Stream binder implementation for Azure Event Hubs.
Unless we have this, the out-of-the-box or the custom apps cannot be built as a messaging-microservice app, where Spring Cloud Stream provides the programming model and Spring Cloud Data Flow lets you orchestrate the individual microserivces in to a data pipeline (i.e., source-processor-sink) via the DSL/Drag-and-Drop GUI.
Microsoft was exploring the binder implementation in the past; possibly it would end up in Azure Spring Boot project. Feel free to drop an issue on their backlog.
We have around 6 individual REST services which we would be calling in our orchestration layer. for example "Calling service-1 to check if a bank account is of certain type, if yes, then call service-2, else call service-3".
Is Spring Integration messaging framework is a right tool for orchestrating calls to those services or its an overkill? Please suggest if there is a better way to accomplish the same.
I can't suggest you better tool, because Spring Integration was the best one for me in the past and now it is my full time job. So, try to find other answers somewhere else.
Now about the point of orchestration with the Spring Integration. To be honest it's just a word which tries to describe the business logic in one application when it calls other external application according some conditions.
So, from big height having HTTP adapters in the Spring Integration, Transformers, Splitters, Routers and Gateways between them, we can say with confidence that messaging layer on Spring Integration fits your requirements and really can help you to distinguish business logic from the orchestration logic.
Not sure what to say else, but I can recommend take a look to the Spring Integration Reference Manual and pay attention to the Routing Slip and Scatter-Gather patterns.