Using VCR to Mock Your Requests

VCR is a tool that I've been using quite often now to mock test requests. But was a bit tricky to find out how it works, so I want to share the knowledge I've been gathering in the past months to explain a bit about VCR.

Transcript

1. USING VCR TO MOCK YOUR REQUESTS
   

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2. SUMMARY
   ● Intro
   ● What is a mock test?
   ● What is VCR?
   ● How to use VCR?
   ● Examples in real life
   ● Bonus: tips & tricks
   ● References
   

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3. WHAT IS A MOCK TEST?
   

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4. WHAT IS A MOCK TEST?
   “Mocking means creating a fake version of an external or internal service that
   can stand in for the real one, helping your tests run more quickly and more
   reliably. When your implementation interacts with an object’s properties, rather
   than its function or behavior, a mock can be used.”
   

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5. WHAT IS VCR?
   

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6. WHAT IS VCR?
   “Record your test suite's HTTP interactions and replay them during future test
   runs for fast, deterministic, accurate tests.”
   

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7. HOW TO USE VCR?
   

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8. ● Whenever you want to test a part of code that requires an external request,
   you use .use_cassette method to state that you want VCR to deal with that
   with a “cassette file”
   ● If there is no fixture yet, VCR is configured by default to create one (this time
   making a real request) so it can be used for future references.
   HOW TO USE VCR?
   

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9. HOW TO USE VCR?
   

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11. SHOWTIME!
    

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12. EXAMPLES IN REAL LIFE
    

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13. EXAMPLES IN REAL LIFE - ELASTIC SITE SEARCH
    

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14. EXAMPLES IN REAL LIFE - ELASTIC SITE SEARCH
    

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15. BONUS: TIPS & TRICKS
    

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16. BONUS: TIPS & TRICKS
    ● There is a configuration option available to filter sensitive data, preventing it
    from being written to the cassette file.
    ● If you wish to continue making real requests while testing, VCR also provide
    other 4 record modes (besides once): new_episodes, none, all and
    record_on_error
    

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17. REFERENCES
    ● https://github.com/anaschwendler/vcr_example
    ● https://dev.to/marleyspoon/using-vcr-to-mock-your-requests-3127
    ● https://github.com/vcr/vcr
    ● https://circleci.com/blog/how-to-test-software-part-i-mocking-stubbing-and-con
    tract-testing/
    ● https://fabioperrella.github.io/10_tips_to_help_using_the_VCR_gem_in_your_r
    uby_test_suite.html
    

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