httr 0.4 is now available on CRAN. The httr packages makes it easy to talk to web APIs from R.

The most important new features are two new vignettes to help you get started and to help you make wrappers for web APIs. Other important improvements include:

  • New headers() and cookies() functions to extract headers and cookies from responses. status_code() returns HTTP status codes.
  • POST() (and PUT(), and PATCH()) now have an encode argument that determine how the body is encoded. Valid values are “multipart”, “form” or “json”, and the multipart argument is now deprecated.
  • GET(..., progress()) will display a progress bar, useful if you’re doing large uploads or downloads.
  • verbose() gives you considerably more control over degree of verbosity, and defaults have been selected to be more helpful for the most common cases.
  • NULL query parameters are now dropped automatically.

There are number of other minor improvements and bug fixes, as described by the release notes.