Providing EDA examples to the community through code, docs, videos and more... we need your feedback/ideas.

[boyney123]

Hello!

This year we want to focus on giving more concrete examples to help the community. These examples will be full-stack applications that consume tooling and specifications from the EDA community.

Goal

To provide more in depth examples of building full-stack EDA applications for the community, including many different approaches like Spec First, Code First, Event First, Event Storming Design all the way through to Implementation. Using specifications (AsyncAPI, CloudEvents, ServerlessWorkflow for example) and tooling to see how far we can go and provide feedback to these tools.

Also, learnings as we go will be shared with blog posts, videos and live streams.

Why

We want to provide the rest of the community with in depth examples to help them understand the EDA landscape and how specs like AsyncAPI and its tooling can help. We want to dogfood our own stuff to provide feedback to the maintainers of the tools with regular feedback on improvements, features etc.

What

We currently have a list of examples we want to explore, which we will share soon, but we would be keen to know if you have any examples you would like to see in the future?

Here are some examples to help you think:

• Build replicas of famous products (frontend, backend with EDA system)
  • To start, this could be your typical retail/ordering system (which many EDA examples focus on)
• Email Queue with RabbitMQ
• IoT Architecture with MQTT

Look forward to seeing what you think and any examples you would like to see.

[boyney123]

Here are some examples that we may focus on

Example List

• Order fulfillment system (Purchase, Delivery, Payment, Inventory)
• Chat Application (Maybe using https://developers.cloudflare.com/workers/learning/using-websockets)
• Food ordering system (JustEat style, pick a dish, wait for confirmation from restaurant etc)
• Email queue (using EDA for an email queuing system)
• IoT system / Home automation systems
• Events into a Datalake
• Twitter Clone
• Multi Car Parking System
  • How many spaces left, take a space, query space, book space online
  • Notification on how many hours left on parking
  • Online parking system
  • Query the parking systems
• Quote System
  • Get prices for X number of thinks from Y numbers of services
• Flight System as seen here

Technologies we may use

• MQTT, Kafka, Serverless, RabbitMQ

Example output

Maybe a master repo somewhere with the examples in it? Mono repo?

• example/{example name}/*
  • diagrams (e.g Architecture Diagram, Event Sourcing Diagram)
  • readme (Describe the domain of the example and its purpose)
• example/{example name}/{tech}/*
  • examples/order-fulfilment/mqtt/*
  • examples/order-fulfilment/kafka/*

Maybe one day

• State machines? For example if events fail etc, how can that be represented in specs/docs etc

[boyney123]

Here is a great example of some ideas from Microsoft https://docs.microsoft.com/en-us/samples/azure-samples/streaming-at-scale/streaming-at-scale/

Some more content for inspiration: https://www.enterpriseintegrationpatterns.com/patterns/messaging/

Also another idea, what if we had a website where we could share EDA patterns / code examples and allow others to contribute simular to https://serverlessland.com/patterns

[boyney123]

I have a suggestion.

Maybe we can start with a basic retail example (hopefully it's simple enough for us to get our head round and we can look at what tooling/specs we wanna try and use to document things).

@fmvilas what do you think, live stream this retail example?

Maybe we can start with a pairing Event Storming session on live stream, and try and find the domains and events we want to write then take things from there?

I'm guessing the end artifact could be

• Event Storming Session Live and Documented
• Document how to translate this into other things (AsyncAPI file for example)
• Generate code/models and actually write an example for this retail example
• Whatever else comes our way....
• Finish with a nice example for people to learn EDA and patterns along the way and how the specifications around EDA fit into the world.

What do you all think?

cc: @fmvilas

[fmvilas]

Yeah, happy to do it live one day next week maybe. It may be a long stream though but I'm all for it. We document the result and continue asynchronously after that. Let's make sure we invite people to join us with enough time before. @derberg thoughts?

[derberg]

are you thinking about Thinking out loud?

[boyney123]

Hey @fmvilas, will ping you/talk to you today about getting a date in.

Think Thinking out loud could make sense, what do you think @fmvilas ?

[fmvilas]

I wasn't thinking on Thinking out loud but that's also a good idea 👍

[boyney123]

So my thoughts to get the ball rolling, is we start with the Fulfilment Example as this is quite popular choice in the EDA community and you see examples all over the internet as it's quite a common one for people to understand.

To make the examples enriched as possible, and hopefully provide value I think we should:

• EventStorm the domain and document it
• Once domain is understood, think about tasks that we can split off into and contribute
• Will be specs, code, docs to write, so contributions welcome everywhere for each example
• We write the code and publish/work in public as we go, getting feedback and working examples.
• We learn + iterate as we go, any issues with specs, tooling etc we raise as we go and contribute back to the eco-system.

Any thoughts?

cc: @fmvilas you cool with this plan of action?

[fmvilas]

Sounds good to me David!

[aschrijver]

Nice. Did this happen?

Edit: I wrote a more elaborate response to the related discussion on Event Storming: https://github.com/orgs/asyncapi/discussions/91#discussioncomment-3721999