The aim of httr is to provide a wrapper for the curl package, customised to the demands of modern web APIs.
- Functions for the most important http verbs: GET(), HEAD(), PATCH(), PUT(), DELETE() and POST().
- Automatic connection sharing across requests to the same website (by default, curl handles are managed automatically), cookies are maintained across requests, and a up-to-date root-level SSL certificate store is used.
- Requests return a standard reponse object that captures the http status line, headers and body, along with other useful information.
- Response content is available with content() as a raw vector (as = "raw"), a character vector (as = "text"), or parsed into an R object (as = "parsed"), currently for html, xml, json, png and jpeg.
- You can convert http errors into R errors with stop_for_status().
- Config functions make it easier to modify the request in common ways: set_cookies(), add_headers(), authenticate(), use_proxy(), verbose(), timeout(), content_type(), accept(), progress().
- Support for OAuth 1.0 and 2.0 with oauth1.0_token() and oauth2.0_token(). The demo directory has eight OAuth demos: four for 1.0 (twitter, vimeo, withings and yahoo) and four for 2.0 (facebook, github, google, linkedin). OAuth credentials are automatically cached within a project.
library(httr) # GET requests: resp <- GET("http://httpbin.org/get") status_code(resp) # status code headers(resp) # headers str(content(resp)) # body # POST requests: # Form encoded resp <- POST(url, body = body, encode = "form") # Multipart encoded resp <- POST(url, body = body, encode = "multipart") # JSON encoded resp <- POST(url, body = body, encode = "json") # setting cookies: resp <- GET("http://httpbin.org/cookies", set_cookies("MeWant" = "cookies")) content(r)$cookies # get response cookies