`auth_prepare()` function

[jonthegeek]

Summary

As an API-wrapping package developer, in order to reuse authentication, I would like to define authorization independent of a request.

Propose signature

auth_prepare(auth_fn, ...)

Also export a version of this corresponding to req_auth_api_key():

auth_api_key(
  parameter_name,
  ...,
  api_key = NULL,
  location = c("header", "query", "cookie"),
  call = rlang::caller_env()
)

Arguments

• auth_fn (function) A function to use to authenticate a request.
• ... (any) Arguments to pass to auth_fn.

Value

Returns a list with class nectar_auth, with elements auth_fn and auth_args.

Behavior

This function is really just a nectar_auth constructor. The function itself will be very simple, but it has a number of downstream effects.

Details

I've never liked the auth_fn + auth_args pattern in req_prepare(). Instead, update req_prepare (in R/req_prepare.R) to take auth as an argument (instead of auth_fn + auth_args). Also add auth_api_key() in R/req_auth_api_key.R, which calls auth_prepare() with auth_fn = req_auth_api_key and the arguments passed into auth_api_key(). Then update vignettes/nectar.Rmd to show this updated pattern (instead of auth_fn + auth_args. We'll also need to update parameter definitions in R/aaa-shared_params.R (since auth_args won't be used anymore), and make sure any examples that reference the old pattern are updated.

This will be a breaking change, but that is ok since this will be implemented before the initial CRAN release.

Note: Do not change tidy_fn + tidy_args in req_prepare() as part of this fix, but we'll definitely use lessons learned here to inform future work to do the same for that pair of arguments.