httrvsem-http-request
The aim of httr is to provide a wrapper for the curl package, customised to the demands of modern web APIs.
Key features:
- 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.
em-http-request is a Ruby gem for making asynchronous HTTP requests using EventMachine. It allows you to perform multiple requests simultaneously and handle the responses as they come in, rather than waiting for each request to complete before making the next one.
In short it supports: - Asynchronous HTTP API for single & parallel request execution - Keep-Alive and HTTP pipelining support - Auto-follow 3xx redirects with max depth - Automatic gzip & deflate decoding - Streaming response processing - Streaming file uploads - HTTP proxy and SOCKS5 support - Basic Auth & OAuth - Connection-level & global middleware support - HTTP parser via http_parser.rb - Works wherever EventMachine runs: Rubinius, JRuby, MRI
Example Use
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
EventMachine.run {
http = EventMachine::HttpRequest.new('http://google.com/').get :query => {'keyname' => 'value'}
# add callback for errors:
http.errback { p 'Uh oh'; EM.stop }
# add callback for successful requests
http.callback {
p http.response_header.status
p http.response_header
p http.response
EventMachine.stop
}
}