couchrest_model/vendor/rest-client/lib/rest_client.rb
2008-06-01 10:11:58 -07:00

132 lines
3 KiB
Ruby

require 'uri'
require 'net/http'
require File.dirname(__FILE__) + '/resource'
# This module's static methods are the entry point for using the REST client.
module RestClient
def self.get(url, headers={})
Request.execute(:method => :get,
:url => url,
:headers => headers)
end
def self.post(url, payload, headers={})
Request.execute(:method => :post,
:url => url,
:payload => payload,
:headers => headers)
end
def self.put(url, payload, headers={})
Request.execute(:method => :put,
:url => url,
:payload => payload,
:headers => headers)
end
def self.delete(url, headers={})
Request.execute(:method => :delete,
:url => url,
:headers => headers)
end
# Internal class used to build and execute the request.
class Request
attr_reader :method, :url, :payload, :headers, :user, :password
def self.execute(args)
new(args).execute
end
def initialize(args)
@method = args[:method] or raise ArgumentError, "must pass :method"
@url = args[:url] or raise ArgumentError, "must pass :url"
@headers = args[:headers] || {}
@payload = process_payload(args[:payload])
@user = args[:user]
@password = args[:password]
end
def execute
execute_inner
rescue Redirect => e
@url = e.message
execute
end
def execute_inner
uri = parse_url(url)
transmit uri, net_http_class(method).new(uri.request_uri, make_headers(headers)), payload
end
def make_headers(user_headers)
final = {}
merged = default_headers.merge(user_headers)
merged.keys.each do |key|
final[key.to_s.gsub(/_/, '-').capitalize] = merged[key]
end
final
end
def net_http_class(method)
Object.module_eval "Net::HTTP::#{method.to_s.capitalize}"
end
def parse_url(url)
url = "http://#{url}" unless url.match(/^http/)
URI.parse(url)
end
# A redirect was encountered; caught by execute to retry with the new url.
class Redirect < RuntimeError; end
# Request failed with an unhandled http error code.
class RequestFailed < RuntimeError; end
# Authorization is required to access the resource specified.
class Unauthorized < RuntimeError; end
def process_payload(p=nil)
unless p.is_a?(Hash)
p
else
@headers[:content_type] = 'application/x-www-form-urlencoded'
p.keys.map { |k| "#{k}=#{URI.escape(p[k].to_s)}" }.join("&")
end
end
def transmit(uri, req, payload)
setup_credentials(req)
Net::HTTP.start(uri.host, uri.port) do |http|
process_result http.request(req, payload || "")
end
end
def setup_credentials(req)
req.basic_auth(user, password) if user
end
def process_result(res)
if %w(200 201 202).include? res.code
res.body
elsif %w(301 302 303).include? res.code
raise Redirect, res.header['Location']
elsif res.code == "401"
raise Unauthorized
else
raise RequestFailed, error_message(res)
end
end
def error_message(res)
"HTTP code #{res.code}: #{res.body}"
end
def default_headers
{ :accept => 'application/xml' }
end
end
end