fixer.io requires an API key, which is saved as an
environmental variable. In interactive mode, using fixer_api_key
will prompt you to enter an API key. You can also use
Sys.setenv(FIXER_API_KEY = <key>) to set the API key.
fixer_api_key(force = FALSE)If TRUE, resets the API key and requires a new key to
be provided, even if one already exists. If FALSE and an API key
already exists, that key will be printed to the console. If no key exists,
you will be prompted to enter a key regardless of the value of
force. Defaults to FALSE.
By default fixerapi will look for the environment variable
FIXER_API_KEY when the package is loaded.