How to make a HTTP request using Ruby on Rails?

Question

You can use Ruby's Net::HTTP class:

require 'net/http'

url = URI.parse('http://www.example.com/index.html')
req = Net::HTTP::Get.new(url.to_s)
res = Net::HTTP.start(url.host, url.port) {|http|
  http.request(req)
}
puts res.body

Net::HTTP is built into Ruby, but let's face it, often it's easier not to use its cumbersome 1980s style and try a higher level alternative:

• HTTP Gem
• HTTParty
• RestClient
• Excon
• Feedjira (RSS only)

OpenURI is the best; it's as simple as

require 'open-uri'
response = open('http://example.com').read

require 'net/http'
result = Net::HTTP.get(URI.parse('http://www.example.com/about.html'))
# or
result = Net::HTTP.get(URI.parse('http://www.example.com'), '/about.html')

I prefer httpclient over Net::HTTP.

client = HTTPClient.new
puts client.get_content('http://www.example.com/index.html')

HTTParty is a good choice if you're making a class that's a client for a service. It's a convenient mixin that gives you 90% of what you need. See how short the Google and Twitter clients are in the examples.

And to answer your second question: no, I wouldn't put this functionality in a controller--I'd use a model instead if possible to encapsulate the particulars (perhaps using HTTParty) and simply call it from the controller.

My favorite two ways to grab the contents of URLs are either OpenURI or Typhoeus.

OpenURI because it's everywhere, and Typhoeus because it's very flexible and powerful.