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: github.com/archiloque/rest-client
Mailing list: [email protected] (send a mail to subscribe).
IRC: #rest-client at freenode

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:[email protected]/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 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 (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::Resource class which provide a lower-level API, 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']

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'

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

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