Kotlin Coroutines

Introduction to Kotlin Coroutines. We went through the basic concepts of Coroutines.

Transcript

1. Kotlin Coroutines Rygel Louv Dakar Ruby Brigade.
2. 2019 Rygel Louv Software engineer
3. - Simplifying asynchronous programming
 - Write async code that looks like sync code
 Coroutines: what problem do they solve ? P . 3
4. Synchronous blocking code P . 3
5. Synchronous blocking code P . 3
6. Async code using a callback P . 3
7. Callback Hell P . 3
8. Coroutines are the best of both worlds P . 3
9. Coroutines create a callback under the hood called Continuation P . 3 Callback
10. State Machine and Continuation Passing Style P . 3
11. What is a coroutine ? P . 3 - Not a thread
 - Takes a piece of code and run it in a thread
 - Lightweight thread
 

12. - Context switching: withContext
 - Dispatchers
 Coroutines concepts P . 3
13. - Dispatcher.Main: Main thread
 - Dispatcher.IO: Network and disk
 - Dispatcher.Default: CPU (heavy computation)
 
 Coroutines dispatchers P . 3
14. - Canceling coroutine execution
 - Following a Lifecycle
 - Informing components when Exception happens
 
 Coroutines concepts: Structured concurrency P . 3 Avoid memory leaks
15. - Keep track of coroutines
 - Ability to cancel them
 - Is notified of failures
 
 Structure concurrency: Scopes P . 3
16. Coroutine scope: launching coroutines P . 3
17. P . 3 Coroutine scope: launching coroutines
18. P . 3 Coroutine scope: launching coroutines Parent Child Scope will get all exceptions thrown by this function
19. - Cancels all coroutines
 - Can not start more coroutines
 Scopes: cancelation P . 3
20. Suspend function in a coroutine P . 3
21. - When a child fails, the scope get notified
 - Then the scope cancel itself and cancel all children
 Scopes exception handling: Job P . 3
22. - The failure of one child does not affect other children
 - When the scope get notified of a failure, nothing happens
 Scopes exception handling: SupervisorJob P . 3
23. Creating coroutines P . 3
24. Creating coroutines: Launch P . 3 - Creates a new coroutine
 - Fire and forget

25. Creating coroutines: Async P . 3 - Creates a new coroutine
 - Returns a value
 Deferred == Promise/Future
26. P . 3
27. Cancellation requires co-operation P . 3
28. Cancellation require co-operation P . 3 - Check if coroutine is Active

29. Next on coroutines P . 3 - Dive deeper in Continuation Passing Style - More on co-operation - Channels - Flows

30. P . 27 THANK YOU