Supercharge your Tests with Factories

This talk will explore the factory pattern and how to leverage it to greatly improve your automated tests. By leaning on Prisma's ORM features and TypeScript types, you'll be able to quickly and painlessly create the exact data your tests need.

Sound interesting? Join our discussion at https://github.com/echobind/prisma-factory!

Transcript

1. With Factories
   Supercharge your
   Tests
   Chris Ball
   @cball_
   

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2. Part 1: Request Tests (Integration Tests)
   Part 2: Resetting the Database & Creating Data
   Part 3: The Factory Pattern & Prisma
   Part 4: E2E Tests
   Part 5: Tips & Tricks
   Tests ❤ Factories,
   Factories ❤
   Supercharge your
   tests with Factories
   Prisma Day 2021
   by Chris Ball
   02
   

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3. 03
   Unit Tests
   Please write them. We're
   focusing higher today.
   Supercharge your
   tests with Factories
   Prisma Day 2021
   by Chris Ball
   

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4. 03
   Request Tests
   API Layer. aka Integration Tests.
   Request
   ➡ Your Code
   ➡ Database
   ➡
   Your Code
   ➡ Response
   Supercharge your
   tests with Factories
   Prisma Day 2021
   by Chris Ball
   

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5. 03
   Supercharge your
   tests with Factories
   Prisma Day 2021
   by Chris Ball
   

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6. 03
   Supercharge your
   tests with Factories
   Prisma Day 2021
   by Chris Ball
   

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7. 03
   Supercharge your
   tests with Factories
   Prisma Day 2021
   by Chris Ball
   

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8. 03
   Supercharge your
   tests with Factories
   Prisma Day 2021
   by Chris Ball
   Inline Snapshots are great!
   (if used properly)
   

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9. 03
   Supercharge your
   tests with Factories
   Prisma Day 2021
   by Chris Ball
   

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10. 03
    Creating Valid Data
    In Request Tests
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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11. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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12. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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13. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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14. 06
    And nothing more.
    Create the data you need for that test
    Check errors, edge cases, proper responses
    Make a request (as a user or a guest) and
    assert the response
    Before each test, make sure the database is reset. Start
    each test with a clean slate.
    Reset the database
    Biggest bang-for-buck at API layer
    Use to test all permissions and edge cases!
    Request Tests
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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15. 03
    The Factory Pattern
    Make it easier to create valid data.
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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16. 03
    Factories?
    A simple object maker.
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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17. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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18. View Slide

19. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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20. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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21. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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22. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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23. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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24. 03
    Why Factories?
    Less brittle tests. Update in
    a single place!
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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25. 06
    This reduces the amount of code you need to write. Add a
    new required attribute? Just update the factory.
    Add defaults for required attributes
    This lets you use the patterns we just discussed. Use Prisma
    types for type safety!
    Add an object that exports build and create
    functions
    ex: Chance.js. Comes in handy with E2E tests. Long or
    unexpected names can break layout.
    Avoids false confidence from copy/pasta!
    Use a faker library for random values
    Make your life easier when creating data
    for your tests.
    Factories
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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26. 03
    E2E Tests
    Frontend Layer.
    Runner
    ➡ Browser
    ➡ Your Code
    ➡
    API call
    ➡ Your Code
    ➡ Browser
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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27. 03
    Factories in E2E
    Example using Cypress.
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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28. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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29. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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30. 03
    Tips & Tricks
    Just a few, don't worry.
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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31. Don't put relationships in your
    factory functions.
    Randomize your eunms
    Leverage fake data to find
    edge cases
    You create additional records you
    may not need.
    Same as above
    Always using known quanities can
    create bugs
    Pass in all relationships via Prisma's
    connect / create methods.
    chance.pickone(Object.values(MyEnum))
    Use the great functions provided by
    chance (or your chosen fake library).
    07
    Tips & Tricks for Factories
    in Prisma
    Tip Why? How?
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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32. 03
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    Tests ❤ Factories,
    Factories ❤
    

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33. 12
    Interested? Want to
    help with this?
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    Discussion at:
    https://github.com/echobind/prisma-factory
    

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34. These patterns and more.
    Echobind's Default Web Template.
    https://github.com/echobind/bisonapp
    12
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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35. @cball_
    11
    Thanks!
    Supercharge your
    tests with Factories
    Prisma Day 2021
    by Chris Ball
    

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