rest_handler.rb in soaspec-0.0.82

- old
+ new
@@ -1,368 +1,368 @@
-
-require_relative 'exchange_handler'
-require_relative '../core_ext/hash'
-require_relative '../not_found_errors'
-require_relative 'handler_accessors'
-require_relative '../interpreter'
-require 'json'
-require 'jsonpath'
-require 'nori'
-require 'erb'
-
-module Soaspec
-
-  # Accessors specific to REST handler
-  module RestAccessors
-
-    # Defines method 'base_url_value' containing base URL used in REST requests
-    # @param [String] url Base Url to use in REST requests. Suburl is appended to this
-    def base_url(url)
-      define_method('base_url_value') do
-        url
-      end
-    end
-
-    # Will create access_token method based on passed parameters
-    def oauth2(client_id: nil, client_secret: nil, token_url: nil, username: nil, password: nil, security_token: nil)
-      define_method('oauth_response') do
-        username = api_username || ERB.new(username).result(binding) if username
-        security_token = ERB.new(security_token).result(binding) if security_token
-        token_url = ERB.new(token_url).result(binding) if token_url
-        password = ERB.new(password).result(binding) if password
-        payload = if password && username
-                    {
-                      grant_type: 'password',
-                      client_id: client_id,
-                      client_secret: client_secret,
-                      username: username,
-                      password: security_token ? (password + security_token) : password,
-                      multipart: true
-                    }
-                  else
-                    {
-                      grant_type: 'client_credentials',
-                      client_id: client_id,
-                      client_secret: client_secret
-                    }
-                  end
-        retry_count = 0
-        begin
-          Soaspec::SpecLogger.add_to 'request_params: ' + payload.to_s
-          response = RestClient.post(token_url, payload, cache_control: 'no_cache', verify_ssl: false)
-        rescue RestClient::Exception => e
-          Soaspec::SpecLogger.add_to("oauth_error: #{e.message}")
-          Soaspec::SpecLogger.add_to("oauth_error: #{e.response}")
-          retry_count += 1
-          retry if retry_count < 3
-          raise e
-        end
-        Soaspec::SpecLogger.add_to("response_headers: #{response.headers}")
-        Soaspec::SpecLogger.add_to("response_body: #{response.body}")
-        JSON.parse(response)
-      end
-
-      define_method('access_token') do
-        oauth_response['access_token']
-      end
-      define_method('instance_url') do
-        oauth_response['instance_url']
-      end
-    end
-
-    # Pass path to YAML file containing OAuth2 parameters
-    # @param [String] path_to_filename Will have Soaspec.credentials_folder appended to it if set
-    def oauth2_file(path_to_filename)
-      full_path = Soaspec.credentials_folder ? File.join(Soaspec.credentials_folder, path_to_filename + '.yml') : path_to_filename + '.yml'
-      file_hash = YAML.load_file(full_path)
-      raise 'File at ' + full_path + ' is not a hash ' unless file_hash.is_a? Hash
-      oauth_hash = file_hash.transform_keys_to_symbols
-      oauth2 **oauth_hash
-    end
-
-    # @param [Hash] headers Hash of REST headers used in RestClient
-    def headers(headers)
-      define_method('rest_client_headers') do
-        headers
-      end
-    end
-
-    # Convert each key from snake_case to PascalCase
-    def pascal_keys(set)
-      define_method('pascal_keys?') do
-        set
-      end
-    end
-
-  end
-
-  # Wraps around Savon client defining default values dependent on the soap request
-  class RestHandler < ExchangeHandler
-    extend Soaspec::RestAccessors
-
-    # User used in making API calls
-    attr_accessor :api_username
-
-    # Set through following method. Base URL in REST requests.
-    def base_url_value
-      nil
-    end
-
-    # Headers used in RestClient
-    def rest_client_headers
-      {}
-    end
-
-    # Add values to here when extending this class to have default REST options.
-    # See rest client resource at https://github.com/rest-client/rest-client for details
-    # It's easier to set headers via 'headers' accessor rather than here
-    # @return [Hash] Options adding to & overriding defaults
-    def rest_resource_options
-      {
-      }
-    end
-
-    # Perform ERB on each header value
-    # @return [Hash] Hash from 'rest_client_headers' passed through ERB
-    def parse_headers
-      Hash[rest_client_headers.map { |k, header| [k, ERB.new(header).result(binding)] }]
-    end
-
-    # Setup object to handle communicating with a particular SOAP WSDL
-    # @param [Hash] options Options defining SOAP request. WSDL, authentication
-    def initialize(name = self.class.to_s, options = {})
-      raise "Base URL not set! Please set in class with 'base_url' method" unless base_url_value
-      @default_hash = {}
-      if name.is_a?(Hash) && options == {} # If name is not set
-        options = name
-        name = self.class.to_s
-      end
-      super
-      set_remove_key(options, :api_username)
-      set_remove_key(options, :default_hash)
-      @init_options = options
-    end
-
-    # Convert snakecase to PascalCase
-    def convert_to_pascal_case(key)
-      return key if /[[:upper:]]/ =~ key[0] # If first character already capital, don't do conversion
-      key.split('_').map(&:capitalize).join
-    end
-
-    # Whether to convert each key in the request to PascalCase
-    # It will also auto convert simple XPath, JSONPath where '//' or '..' not specified
-    # @return Whether to convert to PascalCase
-    def pascal_keys?
-      false
-    end
-
-    # @return [Hash]
-    def hash_used_in_request(override_hash)
-      request = @default_hash.merge(override_hash)
-      if pascal_keys?
-        request.map { |k, v| [convert_to_pascal_case(k.to_s), v] }.to_h
-      else
-        request
-      end
-    end
-
-    # Initialize value of merged options
-    def init_merge_options
-      options = rest_resource_options
-      options[:headers] ||= {}
-      options[:headers].merge! parse_headers
-      options.merge(@init_options)
-    end
-
-    # Used in together with Exchange request that passes such override parameters
-    # @param [Hash] override_parameters Params to characterize REST request
-    # @param_value [params] Extra parameters (E.g. headers)
-    # @param_value [suburl] URL appended to base_url of class
-    # @param_value [method] REST method (:get, :post, etc)
-    def make_request(override_parameters)
-      @merged_options ||= init_merge_options
-      test_values = override_parameters
-      test_values[:params] ||= {}
-      test_values[:method] ||= :post
-      test_values[:suburl] = test_values[:suburl].to_s if test_values[:suburl]
-      test_values[:params][:params] = test_values[:q] if test_values[:q] # Use q for query parameters. Nested :params is ugly and long
-
-      # In order for ERB to be calculated at correct time, the first time request is made, the resource should be created
-      @resource ||= RestClient::Resource.new(ERB.new(base_url_value).result(binding), @merged_options)
-
-      @resource_used = test_values[:suburl] ? @resource[test_values[:suburl]] : @resource
-
-      begin
-      response = case test_values[:method]
-                 when :post, :patch, :put
-                   unless test_values[:payload]
-                     test_values[:payload] = JSON.generate(hash_used_in_request(test_values[:body])).to_s if test_values[:body]
-                   end
-                   @resource_used.send(test_values[:method].to_s, test_values[:payload], test_values[:params])
-                 else
-                   @resource_used.send(test_values[:method].to_s, test_values[:params])
-                 end
-      rescue RestClient::ExceptionWithResponse => e
-        response = e.response
-      end
-      Soaspec::SpecLogger.add_to('response_headers: ' + response.headers.to_s)
-      Soaspec::SpecLogger.add_to('response_body: ' + response.to_s)
-      response
-    end
-
-    # @param [Hash] _format Format of expected result. Ignored for this
-    # @return [Object] Generic body to be displayed in error messages
-    def response_body(response, _format: :hash)
-      extract_hash response
-    end
-
-    def include_in_body?(response, expected)
-      response.body.include? expected
-    end
-
-    # Whether the request found the desired value or not
-    def found?(response)
-      status_code_for(response) != 404
-    end
-
-    # Convert XML or JSON response into a Hash
-    # @param [String] response Response as a String (either in XML or JSON)
-    # @return [Hash]
-    def extract_hash(response)
-      raise ArgumentError("Empty Body. Can't assert on it") if response.body.empty?
-      case Interpreter.response_type_for response
-      when :json
-        converted = JSON.parse(response.body)
-        return converted.transform_keys_to_symbols if converted.is_a? Hash
-        return converted.map!(&:transform_keys_to_symbols) if converted.is_a? Array
-        raise 'Incorrect Type prodcued ' + converted.class
-      when :xml
-        parser = Nori.new(convert_tags_to: lambda { |tag| tag.snakecase.to_sym })
-        parser.parse(response.body)
-      else
-        raise "Neither XML nor JSON detected. It is #{type}. Don't know how to parse It is #{response.body}"
-      end
-    end
-
-    # @return [Boolean] Whether response contains expected value
-    def include_value?(response, expected)
-      extract_hash(response).include_value? expected
-    end
-
-    # @return [Boolean] Whether response body contains expected key
-    def include_key?(response, expected)
-      value_from_path(response, expected)
-    end
-
-    # @return [Integer] HTTP Status code for response
-    def status_code_for(response)
-      response.code
-    end
-
-    # Override this to specify elements that must be present in the response
-    # Will be used in 'success_scenarios' shared examples
-    # @return [Array] Array of symbols specifying element names
-    def mandatory_elements
-      []
-    end
-
-    # Override this to specify xpath results that must be present in the response
-    # Will be used in 'success_scenarios' shared examples
-    # @return [Hash] Hash of 'xpath' => 'expected value' pairs
-    def mandatory_xpath_values
-      {}
-    end
-
-    # Attributes set at the root XML element of SOAP request
-    def root_attributes
-      nil
-    end
-
-    # Returns the value at the provided xpath
-    # @param [RestClient::Response] response
-    # @param [String] xpath
-    # @return [Enumerable] Value inside element found through Xpath
-    def xpath_elements_for(response: nil, xpath: nil, attribute: nil)
-      raise ArgumentError unless response && xpath
-      raise "Can't perform XPATH if response is not XML" unless Interpreter.response_type_for(response) == :xml
-      xpath = "//*[@#{attribute}]" unless attribute.nil?
-      if xpath[0] != '/'
-        xpath = convert_to_pascal_case(xpath) if pascal_keys?
-        xpath = '//' + xpath
-      end
-      if Soaspec.strip_namespaces? && !xpath.include?(':')
-        temp_doc = Nokogiri.parse response.body
-        temp_doc.remove_namespaces!
-        temp_doc.xpath(xpath)
-      else
-        Nokogiri.parse(response.body).xpath(xpath)
-      end
-    end
-
-    # @return [Enumerable] List of values matching JSON path
-    def json_path_values_for(response, path, attribute: nil)
-      raise 'JSON does not support attributes' if attribute
-      if path[0] != '$'
-        path = convert_to_pascal_case(path) if pascal_keys?
-        path = '$..' + path
-      end
-      JsonPath.on(response.body, path)
-    end
-
-    # Based on a exchange, return the value at the provided xpath
-    # If the path does not begin with a '/', a '//' is added to it
-    # @param [Response] response
-    # @param [Object] path Xpath, JSONPath or other path identifying how to find element
-    # @param [String] attribute Generic attribute to find. Will override path
-    # @return [String] Value at Xpath
-    def value_from_path(response, path, attribute: nil)
-      path = path.to_s
-      case Interpreter.response_type_for(response)
-      when :xml
-        result = xpath_elements_for(response: response, xpath: path, attribute: attribute).first
-        raise NoElementAtPath, "No value at Xpath '#{path}'" unless result
-        return result.inner_text if attribute.nil?
-        return result.attributes[attribute].inner_text
-      when :json
-        matching_values = json_path_values_for(response, path, attribute: attribute)
-        raise NoElementAtPath, "Element in #{response.body} not found with path '#{path}'" if matching_values.empty?
-        matching_values.first
-      when :hash
-        response.dig(path.split('.')) # Use path as Hash dig expression separating params via '.' TODO: Unit test
-      else
-        response.to_s[/path/] # Perform regular expression using path if not XML nor JSON TODO: Unit test
-      end
-    end
-
-    # @return [Enumerable] List of values returned from path
-    def values_from_path(response, path, attribute: nil)
-      path = path.to_s
-      case Interpreter.response_type_for(response)
-      when :xml
-        xpath_elements_for(response: response, xpath: path, attribute: attribute).map(&:inner_text)
-      when :json
-        json_path_values_for(response, path, attribute: attribute)
-      else
-        raise "Unable to interpret type of #{response.body}"
-      end
-    end
-
-    # Convenience methods for once off usage of a REST request
-    class << self
-
-      methods = %w[post patch put get delete]
-
-      methods.each do |rest_method|
-        # Make REST Exchange within this Handler context
-        # @param [Hash] params Exchange parameters
-        # @return [Exchange] Instance of Exchange class. Assertions are made by default on the response body
-        define_method(rest_method) do |params|
-          params ||= {}
-          params[:name] ||= rest_method
-          new(params[:name])
-          Exchange.new(params[:name], method: rest_method.to_sym, **params)
-        end
-      end
-    end
-
-  end
+
+require_relative 'exchange_handler'
+require_relative '../core_ext/hash'
+require_relative '../not_found_errors'
+require_relative 'handler_accessors'
+require_relative '../interpreter'
+require 'json'
+require 'jsonpath'
+require 'nori'
+require 'erb'
+
+module Soaspec
+
+  # Accessors specific to REST handler
+  module RestAccessors
+
+    # Defines method 'base_url_value' containing base URL used in REST requests
+    # @param [String] url Base Url to use in REST requests. Suburl is appended to this
+    def base_url(url)
+      define_method('base_url_value') do
+        url
+      end
+    end
+
+    # Will create access_token method based on passed parameters
+    def oauth2(client_id: nil, client_secret: nil, token_url: nil, username: nil, password: nil, security_token: nil)
+      define_method('oauth_response') do
+        username = api_username || ERB.new(username).result(binding) if username
+        security_token = ERB.new(security_token).result(binding) if security_token
+        token_url = ERB.new(token_url).result(binding) if token_url
+        password = ERB.new(password).result(binding) if password
+        payload = if password && username
+                    {
+                      grant_type: 'password',
+                      client_id: client_id,
+                      client_secret: client_secret,
+                      username: username,
+                      password: security_token ? (password + security_token) : password,
+                      multipart: true
+                    }
+                  else
+                    {
+                      grant_type: 'client_credentials',
+                      client_id: client_id,
+                      client_secret: client_secret
+                    }
+                  end
+        retry_count = 0
+        begin
+          Soaspec::SpecLogger.add_to 'request_params: ' + payload.to_s
+          response = RestClient.post(token_url, payload, cache_control: 'no_cache', verify_ssl: false)
+        rescue RestClient::Exception => e
+          Soaspec::SpecLogger.add_to("oauth_error: #{e.message}")
+          Soaspec::SpecLogger.add_to("oauth_error: #{e.response}")
+          retry_count += 1
+          retry if retry_count < 3
+          raise e
+        end
+        Soaspec::SpecLogger.add_to("response_headers: #{response.headers}")
+        Soaspec::SpecLogger.add_to("response_body: #{response.body}")
+        JSON.parse(response)
+      end
+
+      define_method('access_token') do
+        oauth_response['access_token']
+      end
+      define_method('instance_url') do
+        oauth_response['instance_url']
+      end
+    end
+
+    # Pass path to YAML file containing OAuth2 parameters
+    # @param [String] path_to_filename Will have Soaspec.credentials_folder appended to it if set
+    def oauth2_file(path_to_filename)
+      full_path = Soaspec.credentials_folder ? File.join(Soaspec.credentials_folder, path_to_filename + '.yml') : path_to_filename + '.yml'
+      file_hash = YAML.load_file(full_path)
+      raise 'File at ' + full_path + ' is not a hash ' unless file_hash.is_a? Hash
+      oauth_hash = file_hash.transform_keys_to_symbols
+      oauth2 **oauth_hash
+    end
+
+    # @param [Hash] headers Hash of REST headers used in RestClient
+    def headers(headers)
+      define_method('rest_client_headers') do
+        headers
+      end
+    end
+
+    # Convert each key from snake_case to PascalCase
+    def pascal_keys(set)
+      define_method('pascal_keys?') do
+        set
+      end
+    end
+
+  end
+
+  # Wraps around Savon client defining default values dependent on the soap request
+  class RestHandler < ExchangeHandler
+    extend Soaspec::RestAccessors
+
+    # User used in making API calls
+    attr_accessor :api_username
+
+    # Set through following method. Base URL in REST requests.
+    def base_url_value
+      nil
+    end
+
+    # Headers used in RestClient
+    def rest_client_headers
+      {}
+    end
+
+    # Add values to here when extending this class to have default REST options.
+    # See rest client resource at https://github.com/rest-client/rest-client for details
+    # It's easier to set headers via 'headers' accessor rather than here
+    # @return [Hash] Options adding to & overriding defaults
+    def rest_resource_options
+      {
+      }
+    end
+
+    # Perform ERB on each header value
+    # @return [Hash] Hash from 'rest_client_headers' passed through ERB
+    def parse_headers
+      Hash[rest_client_headers.map { |k, header| [k, ERB.new(header).result(binding)] }]
+    end
+
+    # Setup object to handle communicating with a particular SOAP WSDL
+    # @param [Hash] options Options defining SOAP request. WSDL, authentication
+    def initialize(name = self.class.to_s, options = {})
+      raise "Base URL not set! Please set in class with 'base_url' method" unless base_url_value
+      @default_hash = {}
+      if name.is_a?(Hash) && options == {} # If name is not set
+        options = name
+        name = self.class.to_s
+      end
+      super
+      set_remove_key(options, :api_username)
+      set_remove_key(options, :default_hash)
+      @init_options = options
+    end
+
+    # Convert snakecase to PascalCase
+    def convert_to_pascal_case(key)
+      return key if /[[:upper:]]/ =~ key[0] # If first character already capital, don't do conversion
+      key.split('_').map(&:capitalize).join
+    end
+
+    # Whether to convert each key in the request to PascalCase
+    # It will also auto convert simple XPath, JSONPath where '//' or '..' not specified
+    # @return Whether to convert to PascalCase
+    def pascal_keys?
+      false
+    end
+
+    # @return [Hash]
+    def hash_used_in_request(override_hash)
+      request = @default_hash.merge(override_hash)
+      if pascal_keys?
+        request.map { |k, v| [convert_to_pascal_case(k.to_s), v] }.to_h
+      else
+        request
+      end
+    end
+
+    # Initialize value of merged options
+    def init_merge_options
+      options = rest_resource_options
+      options[:headers] ||= {}
+      options[:headers].merge! parse_headers
+      options.merge(@init_options)
+    end
+
+    # Used in together with Exchange request that passes such override parameters
+    # @param [Hash] override_parameters Params to characterize REST request
+    # @param_value [params] Extra parameters (E.g. headers)
+    # @param_value [suburl] URL appended to base_url of class
+    # @param_value [method] REST method (:get, :post, etc)
+    def make_request(override_parameters)
+      @merged_options ||= init_merge_options
+      test_values = override_parameters
+      test_values[:params] ||= {}
+      test_values[:method] ||= :post
+      test_values[:suburl] = test_values[:suburl].to_s if test_values[:suburl]
+      test_values[:params][:params] = test_values[:q] if test_values[:q] # Use q for query parameters. Nested :params is ugly and long
+
+      # In order for ERB to be calculated at correct time, the first time request is made, the resource should be created
+      @resource ||= RestClient::Resource.new(ERB.new(base_url_value).result(binding), @merged_options)
+
+      @resource_used = test_values[:suburl] ? @resource[test_values[:suburl]] : @resource
+
+      begin
+      response = case test_values[:method]
+                 when :post, :patch, :put
+                   unless test_values[:payload]
+                     test_values[:payload] = JSON.generate(hash_used_in_request(test_values[:body])).to_s if test_values[:body]
+                   end
+                   @resource_used.send(test_values[:method].to_s, test_values[:payload], test_values[:params])
+                 else
+                   @resource_used.send(test_values[:method].to_s, test_values[:params])
+                 end
+      rescue RestClient::ExceptionWithResponse => e
+        response = e.response
+      end
+      Soaspec::SpecLogger.add_to('response_headers: ' + response.headers.to_s)
+      Soaspec::SpecLogger.add_to('response_body: ' + response.to_s)
+      response
+    end
+
+    # @param [Hash] _format Format of expected result. Ignored for this
+    # @return [Object] Generic body to be displayed in error messages
+    def response_body(response, _format: :hash)
+      extract_hash response
+    end
+
+    def include_in_body?(response, expected)
+      response.body.include? expected
+    end
+
+    # Whether the request found the desired value or not
+    def found?(response)
+      status_code_for(response) != 404
+    end
+
+    # Convert XML or JSON response into a Hash
+    # @param [String] response Response as a String (either in XML or JSON)
+    # @return [Hash]
+    def extract_hash(response)
+      raise ArgumentError("Empty Body. Can't assert on it") if response.body.empty?
+      case Interpreter.response_type_for response
+      when :json
+        converted = JSON.parse(response.body)
+        return converted.transform_keys_to_symbols if converted.is_a? Hash
+        return converted.map!(&:transform_keys_to_symbols) if converted.is_a? Array
+        raise 'Incorrect Type prodcued ' + converted.class
+      when :xml
+        parser = Nori.new(convert_tags_to: lambda { |tag| tag.snakecase.to_sym })
+        parser.parse(response.body)
+      else
+        raise "Neither XML nor JSON detected. It is #{type}. Don't know how to parse It is #{response.body}"
+      end
+    end
+
+    # @return [Boolean] Whether response contains expected value
+    def include_value?(response, expected)
+      extract_hash(response).include_value? expected
+    end
+
+    # @return [Boolean] Whether response body contains expected key
+    def include_key?(response, expected)
+      value_from_path(response, expected)
+    end
+
+    # @return [Integer] HTTP Status code for response
+    def status_code_for(response)
+      response.code
+    end
+
+    # Override this to specify elements that must be present in the response
+    # Will be used in 'success_scenarios' shared examples
+    # @return [Array] Array of symbols specifying element names
+    def mandatory_elements
+      []
+    end
+
+    # Override this to specify xpath results that must be present in the response
+    # Will be used in 'success_scenarios' shared examples
+    # @return [Hash] Hash of 'xpath' => 'expected value' pairs
+    def mandatory_xpath_values
+      {}
+    end
+
+    # Attributes set at the root XML element of SOAP request
+    def root_attributes
+      nil
+    end
+
+    # Returns the value at the provided xpath
+    # @param [RestClient::Response] response
+    # @param [String] xpath
+    # @return [Enumerable] Value inside element found through Xpath
+    def xpath_elements_for(response: nil, xpath: nil, attribute: nil)
+      raise ArgumentError unless response && xpath
+      raise "Can't perform XPATH if response is not XML" unless Interpreter.response_type_for(response) == :xml
+      xpath = "//*[@#{attribute}]" unless attribute.nil?
+      if xpath[0] != '/'
+        xpath = convert_to_pascal_case(xpath) if pascal_keys?
+        xpath = '//' + xpath
+      end
+      temp_doc = Nokogiri.parse(response.body).dup
+      if Soaspec.strip_namespaces? && !xpath.include?(':')
+        temp_doc.remove_namespaces!
+        temp_doc.xpath(xpath)
+      else
+        temp_doc.xpath(xpath, temp_doc.collect_namespaces)
+      end
+    end
+
+    # @return [Enumerable] List of values matching JSON path
+    def json_path_values_for(response, path, attribute: nil)
+      raise 'JSON does not support attributes' if attribute
+      if path[0] != '$'
+        path = convert_to_pascal_case(path) if pascal_keys?
+        path = '$..' + path
+      end
+      JsonPath.on(response.body, path)
+    end
+
+    # Based on a exchange, return the value at the provided xpath
+    # If the path does not begin with a '/', a '//' is added to it
+    # @param [Response] response
+    # @param [Object] path Xpath, JSONPath or other path identifying how to find element
+    # @param [String] attribute Generic attribute to find. Will override path
+    # @return [String] Value at Xpath
+    def value_from_path(response, path, attribute: nil)
+      path = path.to_s
+      case Interpreter.response_type_for(response)
+      when :xml
+        result = xpath_elements_for(response: response, xpath: path, attribute: attribute).first
+        raise NoElementAtPath, "No value at Xpath '#{path}'" unless result
+        return result.inner_text if attribute.nil?
+        return result.attributes[attribute].inner_text
+      when :json
+        matching_values = json_path_values_for(response, path, attribute: attribute)
+        raise NoElementAtPath, "Element in #{response.body} not found with path '#{path}'" if matching_values.empty?
+        matching_values.first
+      when :hash
+        response.dig(path.split('.')) # Use path as Hash dig expression separating params via '.' TODO: Unit test
+      else
+        response.to_s[/path/] # Perform regular expression using path if not XML nor JSON TODO: Unit test
+      end
+    end
+
+    # @return [Enumerable] List of values returned from path
+    def values_from_path(response, path, attribute: nil)
+      path = path.to_s
+      case Interpreter.response_type_for(response)
+      when :xml
+        xpath_elements_for(response: response, xpath: path, attribute: attribute).map(&:inner_text)
+      when :json
+        json_path_values_for(response, path, attribute: attribute)
+      else
+        raise "Unable to interpret type of #{response.body}"
+      end
+    end
+
+    # Convenience methods for once off usage of a REST request
+    class << self
+
+      methods = %w[post patch put get delete]
+
+      methods.each do |rest_method|
+        # Make REST Exchange within this Handler context
+        # @param [Hash] params Exchange parameters
+        # @return [Exchange] Instance of Exchange class. Assertions are made by default on the response body
+        define_method(rest_method) do |params|
+          params ||= {}
+          params[:name] ||= rest_method
+          new(params[:name])
+          Exchange.new(params[:name], method: rest_method.to_sym, **params)
+        end
+      end
+    end
+
+  end
 end
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