# Cassette Library Dir

The `cassette_library_dir` configuration option sets a directory where VCR saves each cassette.

Note: When using Rails, avoid using the `test/fixtures` directory to store the cassettes. Rails treats any YAML file in the fixtures directory as an ActiveRecord fixture. This will cause an `ActiveRecord::Fixture::FormatError` to be raised.

## cassette\_library\_dir

*Given* a file named "cassette\_library\_dir.rb" with:

```
$server = start_sinatra_app do
  get('/') { "Hello" }
end

require 'vcr'

VCR.configure do |c|
  c.cassette_library_dir = 'vcr/cassettes'
  c.hook_into :webmock
end

VCR.use_cassette('localhost') do
  Net::HTTP.get_response('localhost', '/', $server.port)
end
```

*And* the directory "vcr/cassettes" does not exist

*When* I run `ruby cassette_library_dir.rb`

*Then* the file "vcr/cassettes/localhost.yml" should exist.


---

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