The much hyped "Microservice Architecture" tells us to design our services to be autonomous. Let's find out what this means and how we can achieve it. In this talk I will guide you through the fascinating world of asynchronous communication, event-driven systems and distributed data.

1. Designing for Autonomy
Matthias Noback
@matthiasnoback

4. Microservice envy

5. https://leanpub.com/microservices-for-everyone

6. A microservice architecture
can help you...
- Define team responsibilities
- Scale your development team
- Prevent big balls of mud at the code-level
- Scale horizontally

7. The problem is
designing for autonomy

11. http://www.symfony-project.org/plugins/drTwitterFeedPlugin.html

12. <?php
class drTwitterFeedComponents extends sfComponents
{
public function executeStatusUserTimeline()
{
$query = new TwitterStatusUserTimelineQuery();
$query->setParameters($this->getVar('query_parameters'));
$this->feed = new TwitterStatusCachedFeedDoctrine($query);
$this->feed->fetchTweets();
$this->tweets = $this->feed->getTweets($this->getVar('limit'));
}
}

18. From imperative
To reactive

19. Do this.
Do that.
Do something else.
Do this.
When "this has happened", do that.
When "that has happened", do something else.

22. Process managers

29. Add drawing: states, events and new commands

31. Solving the command issue
1. Process the first step of the process, then emit an event
about it.
2. Let other services respond to this event and take their
own step, emitting an event about it, and so on.

32. Insight in the process
1. Use process managers to send new commands based on
incoming events.
2. Let the process manager keep track of the current state
of each process.

33. What about queries?

36. "What's the current state
of something-something?"

37. The current state is the
result of all past events

44. Solving the query issue
1. Services publish their events.
2. Other services subscribe to these events and update their
own state accordingly.
3. They can build up any projection they like. This gives
them the answers they need, without even asking.

51. Thanks!
https://joind.in/talk/d8d31
@matthiasnoback