= REST Client -- simple DSL for accessing HTTP and REST resources

A simple HTTP and REST client for Ruby, inspired by the Sinatra's microframework style
of specifying actions: get, put, post, delete.

* Main page: http://github.com/archiloque/rest-client
* Mailing list: rest.client@librelist.com (send a mail to subscribe).

== Usage: Raw URL

  require 'rest_client'

  RestClient.get 'http://example.com/resource'

  RestClient.get 'http://example.com/resource', {:params => {:id => 50, 'foo' => 'bar'}}

  RestClient.get 'https://user:password@example.com/private/resource', {:accept => :json}

  RestClient.post 'http://example.com/resource', :param1 => 'one', :nested => { :param2 => 'two' }

  RestClient.post "http://example.com/resource", { 'x' => 1 }.to_json, :content_type => :json, :accept => :json

  RestClient.delete 'http://example.com/resource'

  response = RestClient.get 'http://example.com/resource'
  response.code
  ➔ 200
  response.cookies
  ➔ {"Foo"=>"BAR", "QUUX"=>"QUUUUX"}
  response.headers
  ➔ {:content_type=>"text/html; charset=utf-8", :cache_control=>"private" ...
  response.to_str
  ➔ \n<!DOCTYPE html PUBLIC \"-//W3C//DTD HTML 4.01//EN\"\n   \"http://www.w3.org/TR/html4/strict.dtd\">\n\n<html ....

  RestClient.post( url,
    {
      :transfer => {
        :path => '/foo/bar',
        :owner => 'that_guy',
        :group => 'those_guys'
      },
       :upload => {
        :file => File.new(path, 'rb')
      }
    })

== Multipart

Yeah, that's right!  This does multipart sends for you!

  RestClient.post '/data', :myfile => File.new("/path/to/image.jpg", 'rb')

This does two things for you:

* Auto-detects that you have a File value sends it as multipart
* Auto-detects the mime of the file and sets it in the HEAD of the payload for each entry

If you are sending params that do not contain a File object but the payload needs to be multipart then:

  RestClient.post '/data', :foo => 'bar', :multipart => true

== Usage: ActiveResource-Style

  resource = RestClient::Resource.new 'http://example.com/resource'
  resource.get

  private_resource = RestClient::Resource.new 'https://example.com/private/resource', 'user', 'pass'
  private_resource.put File.read('pic.jpg'), :content_type => 'image/jpg'

See RestClient::Resource module docs for details.

== Usage: Resource Nesting

  site = RestClient::Resource.new('http://example.com')
  site['posts/1/comments'].post 'Good article.', :content_type => 'text/plain'

See RestClient::Resource docs for details.

== Exceptions (see http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html)

* for results code between 200 and 207 a RestClient::Response will be returned
* for results code 301, 302 or 307 the redirection will be followed if the request is a get or a head
* for result code 303 the redirection will be followed and the request transformed into a get
* for other cases a RestClient::Exception holding the Response will be raised, a specific exception class will be thrown for know error codes

   RestClient.get 'http://example.com/resource'
   ➔ RestClient::ResourceNotFound: RestClient::ResourceNotFound

   begin
     RestClient.get 'http://example.com/resource'
   rescue => e
     e.response
   end
   ➔ 404 Resource Not Found | text/html 282 bytes

== Result handling

A block can be passed to the RestClient method, this block will then be called with the Response.
Response.return! can be called to invoke the default response's behavior.

  # Don't raise exceptions but return the response
  RestClient.get('http://example.com/resource'){|response, request, result| response }
  ➔ 404 Resource Not Found | text/html 282 bytes

  # Manage a specific error code
  RestClient.get('http://my-rest-service.com/resource'){ |response, request, result, &block|
    case response.code
    when 200
      p "It worked !"
      response
    when 423
      raise SomeCustomExceptionIfYouWant
    else
      response.return!(request, result, &block)
    end
  }

  # Follow redirections for all request types and not only for get and head
  # RFC : "If the 301, 302 or 307 status code is received in response to a request other than GET or HEAD,
  #        the user agent MUST NOT automatically redirect the request unless it can be confirmed by the user,
  #        since this might change the conditions under which the request was issued."
  RestClient.get('http://my-rest-service.com/resource'){ |response, request, result, &block|
    if [301, 302, 307].include? response.code
      response.follow_redirection(request, result, &block)
    else
      response.return!(request, result, &block)
    end
  }

== Non-normalized URIs.

If you want to use non-normalized URIs, you can normalize them with the addressable gem (http://addressable.rubyforge.org/api/).

  require 'addressable/uri'
  RestClient.get(Addressable::URI.parse("http://www.詹姆斯.com/").normalize.to_str)

== Lower-level access

For cases not covered by the general API, you can use the RestClient::Request class which provide a lower-level API.

You can:

* specify ssl parameters
* override cookies
* manually handle the response (so you can operate on the response stream than reading it fully in memory)

see the class' rdoc for more information.

== Shell

The restclient shell command gives an IRB session with RestClient already loaded:

  $ restclient
  >> RestClient.get 'http://example.com'

Specify a URL argument for get/post/put/delete on that resource:

  $ restclient http://example.com
  >> put '/resource', 'data'

Add a user and password for authenticated resources:

  $ restclient https://example.com user pass
  >> delete '/private/resource'

Create ~/.restclient for named sessions:

  sinatra:
    url: http://localhost:4567
  rack:
    url: http://localhost:9292
  private_site:
    url: http://example.com
    username: user
    password: pass

Then invoke:

  $ restclient private_site

Use as a one-off, curl-style:

  $ restclient get http://example.com/resource > output_body

  $ restclient put http://example.com/resource < input_body

== Logging

To enable logging you can

* set RestClient.log with a ruby Logger
* or set an environment variable to avoid modifying the code (in this case you can use a file name, "stdout" or "stderr"):

   $ RESTCLIENT_LOG=stdout path/to/my/program

Either produces logs like this:

  RestClient.get "http://some/resource"
  # => 200 OK | text/html 250 bytes
  RestClient.put "http://some/resource", "payload"
  # => 401 Unauthorized | application/xml 340 bytes

Note that these logs are valid Ruby, so you can paste them into the restclient
shell or a script to replay your sequence of rest calls.

== Proxy

All calls to RestClient, including Resources, will use the proxy specified by
RestClient.proxy:

  RestClient.proxy = "http://proxy.example.com/"
  RestClient.get "http://some/resource"
  # => response from some/resource as proxied through proxy.example.com

Often the proxy url is set in an environment variable, so you can do this to
use whatever proxy the system is configured to use:

  RestClient.proxy = ENV['http_proxy']

== Query parameters

Request objects know about query parameters and will automatically add them to
the url for GET, HEAD and DELETE requests and escape the keys and values as 
needed:

  RestClient.get 'http://example.com/resource', :params => {:foo => 'bar', :baz => 'qux'}
  # will GET http://example.com/resource?foo=bar&baz=qux

== Cookies

Request and Response objects know about HTTP cookies, and will automatically
extract and set headers for them as needed:

  response = RestClient.get 'http://example.com/action_which_sets_session_id'
  response.cookies
  # => {"_applicatioN_session_id" => "1234"}

  response2 = RestClient.post(
    'http://localhost:3000/',
    {:param1 => "foo"},
    {:cookies => {:session_id => "1234"}}
  )
  # ...response body

== SSL Client Certificates

  RestClient::Resource.new(
    'https://example.com',
    :ssl_client_cert  =>  OpenSSL::X509::Certificate.new(File.read("cert.pem")),
    :ssl_client_key   =>  OpenSSL::PKey::RSA.new(File.read("key.pem"), "passphrase, if any"),
    :ssl_ca_file      =>  "ca_certificate.pem",
    :verify_ssl       =>  OpenSSL::SSL::VERIFY_PEER
  ).get

Self-signed certificates can be generated with the openssl command-line tool.

== Hook

RestClient.add_before_execution_proc add a Proc to be called before each execution, it's handy if you need a direct access to the http request.

Example:

  # Add oath support using the oauth gem
  require 'oauth'
  access_token = ...

  RestClient.add_before_execution_proc do |req, params|
    access_token.sign! req
  end

  RestClient.get 'http://example.com'

== More

Need caching, more advanced logging or any ability provided by a rack middleware ?

Have a look at rest-client-components http://github.com/crohr/rest-client-components

== Meta

Written by Adam Wiggins, major modifications by Blake Mizerany, maintained by Julien Kirch

Patches contributed by many, including Chris Anderson, Greg Borenstein, Ardekantur, Pedro Belo, Rafael Souza, Rick Olson, Aman Gupta, François Beausoleil and Nick Plante.

Released under the MIT License: http://www.opensource.org/licenses/mit-license.php
