Chapter 30 Managing cassettes | HTTP testing in R

30.1 gitignore cassettes

The .gitignore file lets you tell [git][] what files to ignore - those files are not tracked by git and if you share the git repository to the public web, those files in the .gitignore file won’t be shared in the public version.

When using vcr you may want to include your cassettes in the .gitignore file. You may wan to when your cassettes contain sensitive data that you don’t want to have on the internet & dont want to hide with filter_sensitive_data.

You may want to have your cassettes included in your GitHub repo, both to be present when tests run on CI, and when others run your tests.

There’s no correct answer on whether to gitignore your cassettes. Think about security implications and whether you want CI and human contributors to use previously created cassettes or to create/use their own.

30.2 Rbuildignore cassettes

The .Rbuildignore file is used to tell R to ignore certain files/directories.

There’s not a clear use case for why you’d want to add vcr cassettes to your .Rbuildignore file, but if you do be aware that will affect your vcr enabled tests.

30.3 sharing cassettes

Sometimes you may want to share or re-use cassettes across tests, for example to reduce the size for package sources or to test different functionality of your package functions that make the same query under the hood.

To do so, you can use the same cassette name for multiple vcr::use_cassette() calls. vcr::check_cassette_names() will complain about duplicate cassette names, preventing you from accidentally re-using cassettes, however. To allow duplicates, you can provide a character vector of the cassette names you want to re-use to the allowed_duplicates argument of vcr::check_cassette_names(). That way you can use the same cassette across multiple tests.

30.4 deleting cassettes

Removing a cassette is as easy as deleting in your file finder, or from the command line, or from within a text editor or RStudio.

If you delete a cassette, on the next test run the cassette will be recorded again.

If you do want to re-record a test to a cassette, instead of deleting the file you can toggle record modes.

30.5 cassette file types

For right now the only persistence option is yaml. So all files have a .yml extension.

When other persister options are added, additional file types may be found. The next persister type is likely to be JSON, so if you use that option, you’d have .json files instead of .yml files.