314 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			Ruby
		
	
	
	
			
		
		
	
	
			314 lines
		
	
	
		
			10 KiB
		
	
	
	
		
			Ruby
		
	
	
	
| # Copyright 2010 Google Inc.
 | |
| #
 | |
| # Licensed under the Apache License, Version 2.0 (the "License");
 | |
| # you may not use this file except in compliance with the License.
 | |
| # You may obtain a copy of the License at
 | |
| #
 | |
| #      http://www.apache.org/licenses/LICENSE-2.0
 | |
| #
 | |
| # Unless required by applicable law or agreed to in writing, software
 | |
| # distributed under the License is distributed on an "AS IS" BASIS,
 | |
| # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 | |
| # See the License for the specific language governing permissions and
 | |
| # limitations under the License.
 | |
| 
 | |
| 
 | |
| require 'addressable/uri'
 | |
| require 'addressable/template'
 | |
| 
 | |
| require 'google/api_client/errors'
 | |
| 
 | |
| module Google
 | |
|   class APIClient
 | |
|     ##
 | |
|     # A method that has been described by a discovery document.
 | |
|     class Method
 | |
| 
 | |
|       ##
 | |
|       # Creates a description of a particular method.
 | |
|       #
 | |
|       # @param [Addressable::URI] method_base
 | |
|       #   The base URI for the service.
 | |
|       # @param [String] method_name
 | |
|       #   The identifier for the method.
 | |
|       # @param [Hash] method_description
 | |
|       #   The section of the discovery document that applies to this method.
 | |
|       #
 | |
|       # @return [Google::APIClient::Method] The constructed method object.
 | |
|       def initialize(api, method_base, method_name, discovery_document)
 | |
|         @api = api
 | |
|         @method_base = method_base
 | |
|         @name = method_name
 | |
|         @discovery_document = discovery_document
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns the identifier for the method.
 | |
|       #
 | |
|       # @return [String] The method identifier.
 | |
|       attr_reader :name
 | |
| 
 | |
|       ##
 | |
|       # Returns the parsed section of the discovery document that applies to
 | |
|       # this method.
 | |
|       #
 | |
|       # @return [Hash] The method description.
 | |
|       attr_reader :description
 | |
| 
 | |
|       ##
 | |
|       # Returns the base URI for the method.
 | |
|       #
 | |
|       # @return [Addressable::URI]
 | |
|       #   The base URI that this method will be joined to.
 | |
|       attr_reader :method_base
 | |
| 
 | |
|       ##
 | |
|       # Updates the method with the new base.
 | |
|       #
 | |
|       # @param [Addressable::URI, #to_str, String] new_base
 | |
|       #   The new base URI to use for the method.
 | |
|       def method_base=(new_method_base)
 | |
|         @method_base = Addressable::URI.parse(new_method_base)
 | |
|         @uri_template = nil
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns the method ID.
 | |
|       #
 | |
|       # @return [String] The method identifier.
 | |
|       def id
 | |
|         return @discovery_document['id']
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns the HTTP method or 'GET' if none is specified.
 | |
|       #
 | |
|       # @return [String] The HTTP method that will be used in the request.
 | |
|       def http_method
 | |
|         return @discovery_document['httpMethod'] || 'GET'
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns the URI template for the method.  A parameter list can be
 | |
|       # used to expand this into a URI.
 | |
|       #
 | |
|       # @return [Addressable::Template] The URI template.
 | |
|       def uri_template
 | |
|         # TODO(bobaman) We shouldn't be calling #to_s here, this should be
 | |
|         # a join operation on a URI, but we have to treat these as Strings
 | |
|         # because of the way the discovery document provides the URIs.
 | |
|         # This should be fixed soon.
 | |
|         return @uri_template ||= Addressable::Template.new(
 | |
|           self.method_base + @discovery_document['path']
 | |
|         )
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns the Schema object for the method's request, if any.
 | |
|       #
 | |
|       # @return [Google::APIClient::Schema] The request schema.
 | |
|       def request_schema
 | |
|         if @discovery_document['request']
 | |
|           schema_name = @discovery_document['request']['$ref']
 | |
|           return @api.schemas[schema_name]
 | |
|         else
 | |
|           return nil
 | |
|         end
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns the Schema object for the method's response, if any.
 | |
|       #
 | |
|       # @return [Google::APIClient::Schema] The response schema.
 | |
|       def response_schema
 | |
|         if @discovery_document['response']
 | |
|           schema_name = @discovery_document['response']['$ref']
 | |
|           return @api.schemas[schema_name]
 | |
|         else
 | |
|           return nil
 | |
|         end
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Normalizes parameters, converting to the appropriate types.
 | |
|       #
 | |
|       # @param [Hash, Array] parameters
 | |
|       #   The parameters to normalize.
 | |
|       #
 | |
|       # @return [Hash] The normalized parameters.
 | |
|       def normalize_parameters(parameters={})
 | |
|         # Convert keys to Strings when appropriate
 | |
|         if parameters.kind_of?(Hash) || parameters.kind_of?(Array)
 | |
|           # Is a Hash or an Array a better return type?  Do we ever need to
 | |
|           # worry about the same parameter being sent twice with different
 | |
|           # values?
 | |
|           parameters = parameters.inject({}) do |accu, (k, v)|
 | |
|             k = k.to_s if k.kind_of?(Symbol)
 | |
|             k = k.to_str if k.respond_to?(:to_str)
 | |
|             unless k.kind_of?(String)
 | |
|               raise TypeError, "Expected String, got #{k.class}."
 | |
|             end
 | |
|             accu[k] = v
 | |
|             accu
 | |
|           end
 | |
|         else
 | |
|           raise TypeError,
 | |
|             "Expected Hash or Array, got #{parameters.class}."
 | |
|         end
 | |
|         return parameters
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Expands the method's URI template using a parameter list.
 | |
|       #
 | |
|       # @param [Hash, Array] parameters
 | |
|       #   The parameter list to use.
 | |
|       #
 | |
|       # @return [Addressable::URI] The URI after expansion.
 | |
|       def generate_uri(parameters={})
 | |
|         parameters = self.normalize_parameters(parameters)
 | |
|         self.validate_parameters(parameters)
 | |
|         template_variables = self.uri_template.variables
 | |
|         uri = self.uri_template.expand(parameters)
 | |
|         query_parameters = parameters.reject do |k, v|
 | |
|           template_variables.include?(k)
 | |
|         end
 | |
|         if query_parameters.size > 0
 | |
|           uri.query_values = (uri.query_values || {}).merge(query_parameters)
 | |
|         end
 | |
|         # Normalization is necessary because of undesirable percent-escaping
 | |
|         # during URI template expansion
 | |
|         return uri.normalize
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Generates an HTTP request for this method.
 | |
|       #
 | |
|       # @param [Hash, Array] parameters
 | |
|       #   The parameters to send.
 | |
|       # @param [String, StringIO] body The body for the HTTP request.
 | |
|       # @param [Hash, Array] headers The HTTP headers for the request.
 | |
|       #
 | |
|       # @return [Array] The generated HTTP request.
 | |
|       def generate_request(parameters={}, body='', headers=[])
 | |
|         if body.respond_to?(:string)
 | |
|           body = body.string
 | |
|         elsif body.respond_to?(:to_str)
 | |
|           body = body.to_str
 | |
|         else
 | |
|           raise TypeError, "Expected String or StringIO, got #{body.class}."
 | |
|         end
 | |
|         if !headers.kind_of?(Array) && !headers.kind_of?(Hash)
 | |
|           raise TypeError, "Expected Hash or Array, got #{headers.class}."
 | |
|         end
 | |
|         method = self.http_method
 | |
|         uri = self.generate_uri(parameters)
 | |
|         headers = headers.to_a if headers.kind_of?(Hash)
 | |
|         return [method, uri.to_str, headers, [body]]
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns a <code>Hash</code> of the parameter descriptions for
 | |
|       # this method.
 | |
|       #
 | |
|       # @return [Hash] The parameter descriptions.
 | |
|       def parameter_descriptions
 | |
|         @parameter_descriptions ||= (
 | |
|           @discovery_document['parameters'] || {}
 | |
|         ).inject({}) { |h,(k,v)| h[k]=v; h }
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns an <code>Array</code> of the parameters for this method.
 | |
|       #
 | |
|       # @return [Array] The parameters.
 | |
|       def parameters
 | |
|         @parameters ||= ((
 | |
|           @discovery_document['parameters'] || {}
 | |
|         ).inject({}) { |h,(k,v)| h[k]=v; h }).keys
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns an <code>Array</code> of the required parameters for this
 | |
|       # method.
 | |
|       #
 | |
|       # @return [Array] The required parameters.
 | |
|       #
 | |
|       # @example
 | |
|       #   # A list of all required parameters.
 | |
|       #   method.required_parameters
 | |
|       def required_parameters
 | |
|         @required_parameters ||= ((self.parameter_descriptions.select do |k, v|
 | |
|           v['required']
 | |
|         end).inject({}) { |h,(k,v)| h[k]=v; h }).keys
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns an <code>Array</code> of the optional parameters for this
 | |
|       # method.
 | |
|       #
 | |
|       # @return [Array] The optional parameters.
 | |
|       #
 | |
|       # @example
 | |
|       #   # A list of all optional parameters.
 | |
|       #   method.optional_parameters
 | |
|       def optional_parameters
 | |
|         @optional_parameters ||= ((self.parameter_descriptions.reject do |k, v|
 | |
|           v['required']
 | |
|         end).inject({}) { |h,(k,v)| h[k]=v; h }).keys
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Verifies that the parameters are valid for this method.  Raises an
 | |
|       # exception if validation fails.
 | |
|       #
 | |
|       # @param [Hash, Array] parameters
 | |
|       #   The parameters to verify.
 | |
|       #
 | |
|       # @return [NilClass] <code>nil</code> if validation passes.
 | |
|       def validate_parameters(parameters={})
 | |
|         parameters = self.normalize_parameters(parameters)
 | |
|         required_variables = ((self.parameter_descriptions.select do |k, v|
 | |
|           v['required']
 | |
|         end).inject({}) { |h,(k,v)| h[k]=v; h }).keys
 | |
|         missing_variables = required_variables - parameters.keys
 | |
|         if missing_variables.size > 0
 | |
|           raise ArgumentError,
 | |
|             "Missing required parameters: #{missing_variables.join(', ')}."
 | |
|         end
 | |
|         parameters.each do |k, v|
 | |
|           if self.parameter_descriptions[k]
 | |
|             enum = self.parameter_descriptions[k]['enum']
 | |
|             if enum && !enum.include?(v)
 | |
|               raise ArgumentError,
 | |
|                 "Parameter '#{k}' has an invalid value: #{v}. " +
 | |
|                 "Must be one of #{enum.inspect}."
 | |
|             end
 | |
|             pattern = self.parameter_descriptions[k]['pattern']
 | |
|             if pattern
 | |
|               regexp = Regexp.new("^#{pattern}$")
 | |
|               if v !~ regexp
 | |
|                 raise ArgumentError,
 | |
|                   "Parameter '#{k}' has an invalid value: #{v}. " +
 | |
|                   "Must match: /^#{pattern}$/."
 | |
|               end
 | |
|             end
 | |
|           end
 | |
|         end
 | |
|         return nil
 | |
|       end
 | |
| 
 | |
|       ##
 | |
|       # Returns a <code>String</code> representation of the method's state.
 | |
|       #
 | |
|       # @return [String] The method's state, as a <code>String</code>.
 | |
|       def inspect
 | |
|         sprintf(
 | |
|           "#<%s:%#0x ID:%s>",
 | |
|           self.class.to_s, self.object_id, self.id
 | |
|         )
 | |
|       end
 | |
|     end
 | |
|   end
 | |
| end
 |