Let's make this test suite run faster! - BeJUG

Transcript

1. Let's make this test
   suite run faster!
   

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2. David Gageot
   Freelance
   developer
   @dgageot
   javabien.net
   

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3. Why make a test suite run faster?
   

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4. “ I firmly believe it can make
   your product better. Faster to
   test leads to faster to write,
   deploy and use ”
   Anonymous bearded freelance developper
   

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5. You test early and often. Right?
   

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6. Continuous integration?
   

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7. Continuous testing?
   

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8. Continuous deployment?
   

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9. Testing a lot can lead to waiting a lot
   

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10. How wants his coding room to look like
    

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11. Test suite duration can be contained
    

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12. Jenkins slaves to the rescue
    

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13. Jenkins slaves to the rescue. not.
    

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14. Why complicated when it can be simple?
    

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15. I’ll share a few easy tricks
    

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16. “ I firmly believe it can make
    your product better. Faster to
    test leads to faster to write,
    deploy and use ”
    Anonymous bearded freelance developper
    

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17. How can we accelerate the tests?
    The
    Cheater
    The Lazy
    

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18. The
    Cheater
    

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19. Buy a faster machine. Tests are cpu/
    

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20. Thank you
    Q/A
    

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21. BUT single threaded tests get slower
    0
    25
    50
    75
    100
    2007 2008 2009 2010
    

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22. Use all the cores with Maven3
    mvn -T1 clean install : 5:05s
    mvn -T4 clean install : 3:10s
    Beware of
    tests with side
    effects
    

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23. It’s not just me
    

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24. Use all the cores with JUnit/TestNG
    Beware of
    tests with side
    effects
    

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25. That’s it for cheaters
    No silver bullet
    

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26. The Lazy
    

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27. Delete useless tests
    It’s so simple, we don’t do it...
    

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28. Even better, delete dead code
    

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29. Even better, delete dead code
    Leads to deleting even more useless tests
    

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30. Work in a sandbox
    In-memory database H2 behaves much like
    MySql
    As simple as
    changing an
    xml file
    The database is slow
    

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31. It’s Not only SQL
    If going for NoSQL, choose a server that
    can run in-process
    eg. Voldemort
    The network is slow
    

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32. In-memory SMTP Server
    SubEtha SMTP
    

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33. Abstract the filesystem
    Apache VFS (Virtual File System)
    Spring Resource...
    

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34. In-memory everything
    As a bonus, tests
    will run smoother
    

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35. Of course all of these are easier
    to setup at the beginning of a
    project
    

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36. The
    

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37. 5 minutes a day can make a
    difference
    

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38. Don’t test business rules in integration
    Unit tests are often a better place
    

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39. Not the same scale of speed
    10sec
    .01sec
    

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40. Action #1 - Break the longer integration
    Into one faster integration test and a lot of small
    

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41. Action #2 - Mock the slowest layers
    Mocks are
    not just for
    unit tests
    eg. with Spring and Mockito spies
    

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42. Action #3 - Don’t test through the
    Selenium is often overkill
    «But my application is
    complex!»
    «My users want complex
    features,
    My users want Ajax»
    «I need to test browser
    compatibility!»
    

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43. Really?
    

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44. Complexity has a cost
    That you pay each time tests run
    

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45. Test through the browser the strict
    Unit test Javascript
    

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46. Action #4 - Sometimes be old school
    write (easier to test) server-side code
    

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47. Thank you
    Q/A
    

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48. One more thing™
    Action #0 - Simplify and optimize your code
    Tests will run faster
    Keep that one
    secret...
    

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49. Thank you
    Q/A
    

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