For beginners who did not work with spring shell: We will create shell application from the scratch using spring shell with spring boot and use Kotlin as a programming language. For those who have at least some experience: I’ll talk about the problems most often encountered by developers. And how to solve them. Others, who have a strong understanding of Spring Shell: I will tell about non-standard problems and their solutions. Of course, I will mention other alternatives and do some comparison. As a result of the talk, we will know how shell application can be created on JVM language. And you will know the most faced problems and solutions for fixing them.

1. Spring shell for everyone
Ihor Banadiga

2. Ihor Banadiga
JavaDay Lviv, CoffeeJug,
Morning@Lohika, Devoxx
Ukraine, Kotlin Night Kyiv
2
Java Software Engineer at Lohika
#jdo_shell

3. Who don’t?
3

4. Who did?
4

5. Who do?
5

6. Who done?
6

7. Agenda
● How to start
● Resolve base problems
● Remote usage
● Build “muscles”
7

8. What is shell?
8
Before we start...

9. Shell
● sh
● bash
● zsh
9
● aws-shell
● mysql
● mongo

10. Why?
10
One more question...

11. Why?
● Local execution
● Remote execution
● Complete solution
● Professional users
● Accessibility
11

12. Why me?
12
One more question...

13. My case
● Many services
● Background processing
● Data analysis / automatization
● No UI
● Operators / Devops
● Limited time
13

14. Spring Shell
14
Spring framework

15. Coding session
15
Client bank
#jdo_shell

16. 16
Summary
Client bank coding session

17. Summary
● Define commands
● Define parameters
● Entering extra params
● Group commands
● Commands availability
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● Customize prompt
● Autocompletion
● Converter implementation
● Help generation

18. Looks cool
18
No one is perfect

19. What are the cons?
19

20. Cons
● Testing
● Time to start
● Logging
● Upgrade
● Update
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● Configuration
● Network
● etc

21. How can we deal with it?
21

22. 22
Thin client
Move shell to server

23. Coding session
23
Move client bank to server
#jdo_shell

24. 24
Summary
Client bank on server

25. Summary
● SSH support
● Time to start / Time to connect
● Logs on server
● Upgrade / Update on server
● Configuration
● Network
25
● JVM ecosystem
● Post processors
● Actuator as shell
● Testing

26. 26
Question?
Thanks!
#jdo_shell

27. Thanks!
27
Slide Code
#jdo_shell

28. Links
28
● Slide https://www.slideshare.net/IhorBanadiga/spring-shell-for-everyone
● Demo https://github.com/banadiga/shell-application
● Client bank https://github.com/banadiga/client-bank
● Spring shell project https://projects.spring.io/spring-shell/
● SSH shell https://github.com/fonimus/ssh-shell-spring-boot