Event Driven Design is the implementation of requirements through a queue of events that are triggered by user input. Callback functions only create event objects and add them to the queue so state remains unchanged.
Questions tagged [event-driven-design]
241 questions
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Webhook (Push) vs Asynchronous Queue (Push) Architecture
When building webhooks, it's a best practice for the consumer of the webhook (e.g. the receiver of the webhook) to immediately drop any messages received into a queue to prevent it from "backing up" the delivery of subsequent messages. This seems to…
user1431072
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ddd: remove entity (microservice) dependent of other (microservice)
We've two domains: Departments and Employees.
Both of them are microservices and we're using an event bus (kafka) to populate events.
As usual, department can have several employees.
Currently, we've implemented "Deleted Deployment" use…
Jordi
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Workflow engine with events
I'm researching a workflow engine to organize some system flows.
As part of the research I want to build a small workflow poc:
The workflow should listen to some event and than start (lets say customer A created)
The flow is:
Publish a work message…
Shachar Radoshinsky
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Is there a specification for commands similar to events in OpenAPI?
I am building a microservice application, and I try to follow the best practices. I use event sourcing and event driven state transfer in many places, but I realized that sometimes I just need to call another service in an asynchronous way to kindly…
Ra0k
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Guava Async eventbus listeners are triggered sequentially
I'm working on a Java application which emits events which should be handled asynchronously, since the event handling is IO dependent and I want it to be decoupled from core logic.
I'm trying out Guava EventBus for this use case. In order to enable…
forcehandler
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How to keep a view table updated on CQRS/Event Sourcing patterns
What is the best way to keep a view table up to date, using the CQRS/Event Sourcing pattern?
The most common way is through KSQL queries, but I would like to know if there is a more generic way, for example, using a relational database.
The more…
juanmorschrott
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Restrict Kafka consumers based on event headers (metadata)
The book "Building Event-Driven Microservices" gives good practice to use a metatags (event headers) for placing restrictions on Kafka consumers. One of which is the following:
Deprecation:
A way to indicate that a stream is out of date. Marking an…
zashto
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What is the best event processing design / pattern to match 2 asynchronous events to create a 3rd consolidated event?
What is the best possible way to create a consolidated event (output) from 2 different asynchronous input event in the realtime?
Take for example
"input_event_A" : { "correlation_id" : "abc_123", "payload_event_a": { some event A data }…
user1697113
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How can microservice based applications use Service Mesh and Event Driven Architecture together?
I came across some applications where they say they use Event Driven Architecture to communicate between microservices (Kafka as event broker) and also a Service Mesh (LinkerD)
There are a couple of questions I have not found answers for:
As I read…
jhthewow
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Microservice API Gateway Pattern - question about two design options
In the standard micro service API gateway pattern (if you research any major site discussing this pattern ) you will see the same api gateway pattern in which one or more API Gateway(s) sit in front of one or more micro services and communicates…
Matt
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Components in the same application that send events/commands to themselves
Is it common for event-driven architectures to have components in the same application that send events/commands to themselves ? (take a look at the below picture).
I have this weird scenario at work and it doesn't seem quite right.
Example of…
Kick
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How to handle changes to data structure in an Event Driven Microservice Architecture?
So say I have a system built on an Event Driven Microservice Architecture,
I have a service that invites new team members to an organization.
The service publishes an object that looks like so
{
...
"from": "my_name@mail.com",
invites: [
…
Katty Kay
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How to model account balance check? (Is it possible with eventual consistency / event driven architecture?)
If there are 2 bounded contexts: Spending and Account management, how to prevent so the user doesn't spend more than he has in balance?
I understand the case when we have Order > Payment > Shipment sequence for a single product, but here it's more …
dee zg
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node.js asynchronous initialization issue
I am creating a node.js module which communicates with a program through XML-RPC. The API for this program changed recently after a certain version. For this reason, when a client is created (createClient) I want to ask the program its version…
Jorge Israel Peña
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Azure event hub - How to consume events parallelly using the official SDK?
I've setup the following test:
Craeted a azure event hub with 10 partitions
Created a single storage account
Created a single consumer group
Filled the hub with 10k messages
Created 2 containers (on AKS) that would basically consume those events…
Leonardo
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