require 'net/https' require 'date' require 'time' require 'uri' require 'benchmark' module ActiveResource class ConnectionError < StandardError # :nodoc: attr_reader :response def initialize(response, message = nil) @response = response @message = message end def to_s "Failed with #{response.code}" end end # 4xx Client Error class ClientError < ConnectionError; end # :nodoc: # 404 Not Found class ResourceNotFound < ClientError; end # :nodoc: # 409 Conflict class ResourceConflict < ClientError; end # :nodoc: # 5xx Server Error class ServerError < ConnectionError; end # :nodoc: # 405 Method Not Allowed class MethodNotAllowed < ClientError # :nodoc: def allowed_methods @response['Allow'].split(',').map { |verb| verb.strip.downcase.to_sym } end end # Class to handle connections to remote web services. # This class is used by ActiveResource::Base to interface with REST # services. class Connection attr_reader :site class << self def requests @@requests ||= [] end def default_header class << self ; attr_reader :default_header end @default_header = { 'Content-Type' => 'application/xml' } end end # The +site+ parameter is required and will set the +site+ # attribute to the URI for the remote resource service. def initialize(site) raise ArgumentError, 'Missing site URI' unless site self.site = site end # Set URI for remote service. def site=(site) @site = site.is_a?(URI) ? site : URI.parse(site) end # Execute a GET request. # Used to get (find) resources. def get(path, headers = {}) xml_from_response(request(:get, path, build_request_headers(headers))) end # Execute a DELETE request (see HTTP protocol documentation if unfamiliar). # Used to delete resources. def delete(path, headers = {}) request(:delete, path, build_request_headers(headers)) end # Execute a PUT request (see HTTP protocol documentation if unfamiliar). # Used to update resources. def put(path, body = '', headers = {}) request(:put, path, body.to_s, build_request_headers(headers)) end # Execute a POST request. # Used to create new resources. def post(path, body = '', headers = {}) request(:post, path, body.to_s, build_request_headers(headers)) end def xml_from_response(response) from_xml_data(Hash.from_xml(response.body)) end private # Makes request to remote service. def request(method, path, *arguments) logger.info "#{method.to_s.upcase} #{site.scheme}://#{site.host}:#{site.port}#{path}" if logger result = nil time = Benchmark.realtime { result = http.send(method, path, *arguments) } logger.info "--> #{result.code} #{result.message} (#{result.body.length}b %.2fs)" % time if logger handle_response(result) end # Handles response and error codes from remote service. def handle_response(response) case response.code.to_i when 200...400 response when 404 raise(ResourceNotFound.new(response)) when 405 raise(MethodNotAllowed.new(response)) when 409 raise(ResourceConflict.new(response)) when 422 raise(ResourceInvalid.new(response)) when 401...500 raise(ClientError.new(response)) when 500...600 raise(ServerError.new(response)) else raise(ConnectionError.new(response, "Unknown response code: #{response.code}")) end end # Creates new (or uses currently instantiated) Net::HTTP instance for communication with # remote service and resources. def http unless @http @http = Net::HTTP.new(@site.host, @site.port) @http.use_ssl = @site.is_a?(URI::HTTPS) @http.verify_mode = OpenSSL::SSL::VERIFY_NONE if @http.use_ssl end @http end # Builds headers for request to remote service. def build_request_headers(headers) authorization_header.update(self.class.default_header).update(headers) end # Sets authorization header; authentication information is pulled from credentials provided with site URI. def authorization_header (@site.user || @site.password ? { 'Authorization' => 'Basic ' + ["#{@site.user}:#{ @site.password}"].pack('m').delete("\r\n") } : {}) end def logger #:nodoc: ActiveResource::Base.logger end # Manipulate from_xml Hash, because xml_simple is not exactly what we # want for ActiveResource. def from_xml_data(data) if data.is_a?(Hash) && data.keys.size == 1 data.values.first else data end end end end