# See the License for the specific language governing permissions and
# limitations under the License.
+
require 'httpadapter'
require 'json'
+require 'stringio'
+require 'google/api_client/errors'
+require 'google/api_client/environment'
require 'google/api_client/discovery'
module Google
# TODO(bobaman): Document all this stuff.
+
##
- # This class manages communication with a single API.
+ # This class manages APIs communication.
class APIClient
##
- # An error which is raised when there is an unexpected response or other
- # transport error that prevents an operation from succeeding.
- class TransmissionError < StandardError
- end
-
+ # Creates a new Google API client.
+ #
+ # @param [Hash] options The configuration parameters for the client.
+ # @option options [Symbol, #generate_authenticated_request] :authorization
+ # (:oauth_1)
+ # The authorization mechanism used by the client. The following
+ # mechanisms are supported out-of-the-box:
+ # <ul>
+ # <li><code>:two_legged_oauth_1</code></li>
+ # <li><code>:oauth_1</code></li>
+ # <li><code>:oauth_2</code></li>
+ # </ul>
+ # @option options [String] :host ("www.googleapis.com")
+ # The API hostname used by the client. This rarely needs to be changed.
+ # @option options [String] :application_name
+ # The name and version of the application using the client. This should
+ # be given in the form `"{name}/{version}"`.
+ # @option options [String] :user_agent
+ # ("{app_name} google-api-ruby-client/{version} {os_name}/{os_version}")
+ # The user agent used by the client. Most developers will want to
+ # leave this value alone and use the `:application_name` option instead.
def initialize(options={})
- @options = {
- # TODO: What configuration options need to go here?
- }.merge(options)
- if !self.authorization.respond_to?(:generate_authenticated_request)
- raise TypeError,
- 'Expected authorization mechanism to respond to ' +
- '#generate_authenticated_request.'
+ # Normalize key to String to allow indifferent access.
+ options = options.inject({}) do |accu, (key, value)|
+ accu[key.to_s] = value
+ accu
+ end
+ # Almost all API usage will have a host of 'www.googleapis.com'.
+ self.host = options["host"] || 'www.googleapis.com'
+ # Most developers will want to leave this value alone and use the
+ # application_name option.
+ self.user_agent = options["user_agent"] || (
+ (options["application_name"] || '')
+ 'google-api-ruby-client/' + VERSION::STRING +
+ ' ' + ENV::OS_VERSION
+ ).strip
+ # This is mostly a default for the sake of convenience.
+ # Unlike most other options, this one may be nil, so we check for
+ # the presence of the key rather than checking the value.
+ if options.has_key?("parser")
+ self.parser = options["parser"]
+ else
+ require 'google/api_client/parsers/json_parser'
+ # NOTE: Do not rely on this default value, as it may change
+ self.parser = Google::APIClient::JSONParser
+ end
+ # The writer method understands a few Symbols and will generate useful
+ # default authentication mechanisms.
+ self.authorization = options["authorization"] || :oauth_2
+ # The HTTP adapter controls all of the HTTP traffic the client generates.
+ # By default, Net::HTTP is used, but adding support for other clients
+ # is trivial.
+ if options["http_adapter"]
+ self.http_adapter = options["http_adapter"]
+ else
+ require 'httpadapter/adapters/net_http'
+ # NOTE: Do not rely on this default value, as it may change
+ self.http_adapter = HTTPAdapter::NetHTTPAdapter.new
end
+ @discovery_uris = {}
+ @discovery_documents = {}
+ @discovered_apis = {}
+ return self
end
+
##
# Returns the parser used by the client.
- def parser
- unless @options[:parser]
- require 'google/api_client/parsers/json_parser'
- # NOTE: Do not rely on this default value, as it may change
- @options[:parser] = JSONParser
+ #
+ # @return [#serialize, #parse]
+ # The parser used by the client. Any object that implements both a
+ # <code>#serialize</code> and a <code>#parse</code> method may be used.
+ # If <code>nil</code>, no parsing will be done.
+ attr_reader :parser
+
+ ##
+ # Sets the parser used by the client.
+ #
+ # @param [#serialize, #parse] new_parser
+ # The parser used by the client. Any object that implements both a
+ # <code>#serialize</code> and a <code>#parse</code> method may be used.
+ # If <code>nil</code>, no parsing will be done.
+ def parser=(new_parser)
+ if new_parser &&
+ !new_parser.respond_to?(:serialize) &&
+ !new_parser.respond_to?(:parse)
+ raise TypeError,
+ 'Expected parser object to respond to #serialize and #parse.'
end
- return @options[:parser]
+ @parser = new_parser
end
##
# Returns the authorization mechanism used by the client.
- def authorization
- unless @options[:authorization]
+ #
+ # @return [#generate_authenticated_request] The authorization mechanism.
+ attr_reader :authorization
+
+ ##
+ # Sets the authorization mechanism used by the client.
+ #
+ # @param [#generate_authenticated_request] new_authorization
+ # The new authorization mechanism.
+ def authorization=(new_authorization)
+ case new_authorization
+ when :oauth_1, :oauth
require 'signet/oauth_1/client'
# NOTE: Do not rely on this default value, as it may change
- @options[:authorization] = Signet::OAuth1::Client.new(
+ new_authorization = Signet::OAuth1::Client.new(
:temporary_credential_uri =>
'https://www.google.com/accounts/OAuthGetRequestToken',
:authorization_uri =>
:client_credential_key => 'anonymous',
:client_credential_secret => 'anonymous'
)
+ when :two_legged_oauth_1, :two_legged_oauth
+ require 'signet/oauth_1/client'
+ # NOTE: Do not rely on this default value, as it may change
+ new_authorization = Signet::OAuth1::Client.new(
+ :client_credential_key => nil,
+ :client_credential_secret => nil,
+ :two_legged => true
+ )
+ when :oauth_2
+ require 'signet/oauth_2/client'
+ # NOTE: Do not rely on this default value, as it may change
+ new_authorization = Signet::OAuth2::Client.new(
+ :authorization_uri =>
+ 'https://accounts.google.com/o/oauth2/auth',
+ :token_credential_uri =>
+ 'https://accounts.google.com/o/oauth2/token'
+ )
+ when nil
+ # No authorization mechanism
+ else
+ if !new_authorization.respond_to?(:generate_authenticated_request)
+ raise TypeError,
+ 'Expected authorization mechanism to respond to ' +
+ '#generate_authenticated_request.'
+ end
end
- return @options[:authorization]
+ @authorization = new_authorization
+ return @authorization
end
##
# Returns the HTTP adapter used by the client.
- def http_adapter
- return @options[:http_adapter] ||= (begin
- require 'httpadapter/adapters/net_http'
- @options[:http_adapter] = HTTPAdapter::NetHTTPRequestAdapter
- end)
+ #
+ # @return [HTTPAdapter]
+ # The HTTP adapter object. The object must include the
+ # HTTPAdapter module and conform to its interface.
+ attr_reader :http_adapter
+
+ ##
+ # Returns the HTTP adapter used by the client.
+ #
+ # @return [HTTPAdapter]
+ # The HTTP adapter object. The object must include the
+ # HTTPAdapter module and conform to its interface.
+ def http_adapter=(new_http_adapter)
+ if new_http_adapter.kind_of?(HTTPAdapter)
+ @http_adapter = new_http_adapter
+ else
+ raise TypeError, "Expected HTTPAdapter, got #{new_http_adapter.class}."
+ end
+ end
+
+ ##
+ # The API hostname used by the client.
+ #
+ # @return [String]
+ # The API hostname. Should almost always be 'www.googleapis.com'.
+ attr_accessor :host
+
+ ##
+ # The user agent used by the client.
+ #
+ # @return [String]
+ # The user agent string used in the User-Agent header.
+ attr_accessor :user_agent
+
+ ##
+ # Returns the URI for the directory document.
+ #
+ # @return [Addressable::URI] The URI of the directory document.
+ def directory_uri
+ template = Addressable::Template.new(
+ "https://{host}/discovery/v1/apis"
+ )
+ return template.expand({"host" => self.host})
+ end
+
+ ##
+ # Manually registers a URI as a discovery document for a specific version
+ # of an API.
+ #
+ # @param [String, Symbol] api The service name.
+ # @param [String] version The desired version of the service.
+ # @param [Addressable::URI] uri The URI of the discovery document.
+ def register_discovery_uri(api, version, uri)
+ api = api.to_s
+ version = version || 'v1'
+ @discovery_uris["#{api}:#{version}"] = uri
end
##
# Returns the URI for the discovery document.
#
+ # @param [String, Symbol] api The service name.
+ # @param [String] version The desired version of the service.
# @return [Addressable::URI] The URI of the discovery document.
- def discovery_uri
- return @options[:discovery_uri] ||= (begin
- if @options[:service]
- service_id = @options[:service]
- service_version = @options[:service_version] || 'v1'
- Addressable::URI.parse(
- "http://www.googleapis.com/discovery/0.1/describe" +
- "?api=#{service_id}"
- )
+ def discovery_uri(api, version=nil)
+ api = api.to_s
+ version = version || 'v1'
+ return @discovery_uris["#{api}:#{version}"] ||= (begin
+ template = Addressable::Template.new(
+ "https://{host}/discovery/v1/apis/" +
+ "{api}/{version}/rest"
+ )
+ template.expand({
+ "host" => self.host,
+ "api" => api,
+ "version" => version
+ })
+ end)
+ end
+
+ ##
+ # Manually registers a pre-loaded discovery document for a specific version
+ # of an API.
+ #
+ # @param [String, Symbol] api The service name.
+ # @param [String] version The desired version of the service.
+ # @param [String, StringIO] discovery_document
+ # The contents of the discovery document.
+ def register_discovery_document(api, version, discovery_document)
+ api = api.to_s
+ version = version || 'v1'
+ if discovery_document.kind_of?(StringIO)
+ discovery_document.rewind
+ discovery_document = discovery_document.string
+ elsif discovery_document.respond_to?(:to_str)
+ discovery_document = discovery_document.to_str
+ else
+ raise TypeError,
+ "Expected String or StringIO, got #{discovery_document.class}."
+ end
+ @discovery_documents["#{api}:#{version}"] =
+ JSON.parse(discovery_document)
+ end
+
+ ##
+ # Returns the parsed directory document.
+ #
+ # @return [Hash] The parsed JSON from the directory document.
+ def directory_document
+ return @directory_document ||= (begin
+ request_uri = self.directory_uri
+ request = ['GET', request_uri, [], []]
+ response = self.transmit_request(request)
+ status, headers, body = response
+ if status == 200 # TODO(bobaman) Better status code handling?
+ merged_body = StringIO.new
+ body.each do |chunk|
+ merged_body.write(chunk)
+ end
+ merged_body.rewind
+ JSON.parse(merged_body.string)
else
- raise ArgumentError,
- 'Missing required configuration value, :discovery_uri.'
+ raise TransmissionError,
+ "Could not retrieve discovery document at: #{request_uri}"
end
end)
end
##
# Returns the parsed discovery document.
#
+ # @param [String, Symbol] api The service name.
+ # @param [String] version The desired version of the service.
# @return [Hash] The parsed JSON from the discovery document.
- def discovery_document
- return @discovery_document ||= (begin
- request = ['GET', self.discovery_uri.to_s, [], []]
+ def discovery_document(api, version=nil)
+ api = api.to_s
+ version = version || 'v1'
+ return @discovery_documents["#{api}:#{version}"] ||= (begin
+ request_uri = self.discovery_uri(api, version)
+ request = ['GET', request_uri, [], []]
response = self.transmit_request(request)
status, headers, body = response
if status == 200 # TODO(bobaman) Better status code handling?
JSON.parse(merged_body.string)
else
raise TransmissionError,
- "Could not retrieve discovery document at: #{self.discovery_uri}"
+ "Could not retrieve discovery document at: #{request_uri}"
end
end)
end
##
- # Returns a list of services this client instance has performed discovery
- # for. This may return multiple versions of the same service.
- #
- # @return [Array]
- # A list of discovered <code>Google::APIClient::Service</code> objects.
- def discovered_services
- return @discovered_services ||= (begin
- service_names = self.discovery_document['data'].keys()
- services = []
- for service_name in service_names
- versions = self.discovery_document['data'][service_name]
- for service_version in versions.keys()
- service_description =
- self.discovery_document['data'][service_name][service_version]
- services << ::Google::APIClient::Service.new(
- service_name,
- service_version,
- service_description
+ # Returns all APIs published in the directory document.
+ #
+ # @return [Array] The list of available APIs.
+ def discovered_apis
+ @directory_apis ||= (begin
+ document_base = self.directory_uri
+ if self.directory_document && self.directory_document['items']
+ self.directory_document['items'].map do |discovery_document|
+ ::Google::APIClient::API.new(
+ document_base,
+ discovery_document
)
end
+ else
+ []
end
- services
end)
end
##
# Returns the service object for a given service name and service version.
#
- # @param [String, Symbol] service_name The service name.
- # @param [String] service_version The desired version of the service.
+ # @param [String, Symbol] api The service name.
+ # @param [String] version The desired version of the service.
#
- # @return [Google::APIClient::Service] The service object.
- def discovered_service(service_name, service_version='v1')
- if !service_name.kind_of?(String) && !service_name.kind_of?(Symbol)
+ # @return [Google::APIClient::API] The service object.
+ def discovered_api(api, version=nil)
+ if !api.kind_of?(String) && !api.kind_of?(Symbol)
raise TypeError,
- "Expected String or Symbol, got #{service_name.class}."
+ "Expected String or Symbol, got #{api.class}."
end
- service_name = service_name.to_s
- for service in self.discovered_services
- if service.name == service_name &&
- service.version.to_s == service_version.to_s
- return service
+ api = api.to_s
+ version = version || 'v1'
+ return @discovered_apis["#{api}:#{version}"] ||= begin
+ document_base = self.discovery_uri(api, version)
+ discovery_document = self.discovery_document(api, version)
+ if document_base && discovery_document
+ ::Google::APIClient::API.new(
+ document_base,
+ discovery_document
+ )
+ else
+ nil
end
end
- return nil
end
##
# Returns the method object for a given RPC name and service version.
#
# @param [String, Symbol] rpc_name The RPC name of the desired method.
- # @param [String] service_version The desired version of the service.
+ # @param [String] version The desired version of the service.
#
# @return [Google::APIClient::Method] The method object.
- def discovered_method(rpc_name, service_version='v1')
+ def discovered_method(rpc_name, api, version=nil)
if !rpc_name.kind_of?(String) && !rpc_name.kind_of?(Symbol)
raise TypeError,
"Expected String or Symbol, got #{rpc_name.class}."
end
rpc_name = rpc_name.to_s
- for service in self.discovered_services
- # This looks kinda weird, but is not a real problem because there's
- # almost always only one service, and this is memoized anyhow.
- if service.version.to_s == service_version.to_s
- return service.to_h[rpc_name] if service.to_h[rpc_name]
- end
+ api = api.to_s
+ version = version || 'v1'
+ service = self.discovered_api(api, version)
+ if service.to_h[rpc_name]
+ return service.to_h[rpc_name]
+ else
+ return nil
end
- return nil
end
##
# Returns the service object with the highest version number.
#
- # <em>Warning</em>: This method should be used with great care. As APIs
- # are updated, minor differences between versions may cause
+ # @note <em>Warning</em>: This method should be used with great care.
+ # As APIs are updated, minor differences between versions may cause
# incompatibilities. Requesting a specific version will avoid this issue.
#
- # @param [String, Symbol] service_name The name of the service.
+ # @param [String, Symbol] api The name of the service.
#
- # @return [Google::APIClient::Service] The service object.
- def latest_service(service_name)
- if !service_name.kind_of?(String) && !service_name.kind_of?(Symbol)
+ # @return [Google::APIClient::API] The service object.
+ def preferred_version(api)
+ if !api.kind_of?(String) && !api.kind_of?(Symbol)
raise TypeError,
- "Expected String or Symbol, got #{service_name.class}."
+ "Expected String or Symbol, got #{api.class}."
end
- service_name = service_name.to_s
- versions = {}
- for service in self.discovered_services
- next if service.name != service_name
- sortable_version = service.version.gsub(/^v/, '').split('.').map do |v|
- v.to_i
- end
- versions[sortable_version] = service
+ api = api.to_s
+ # TODO(bobaman): Update to use directory API.
+ return self.discovered_apis.detect do |a|
+ a.name == api && a.preferred == true
end
- return versions[versions.keys.sort.last]
end
##
# The method object or the RPC name of the method being executed.
# @param [Hash, Array] parameters
# The parameters to send to the method.
- # @param [String] The body of the request.
+ # @param [String] body The body of the request.
# @param [Hash, Array] headers The HTTP headers for the request.
# @param [Hash] options
# The configuration parameters for the request.
- # - <code>:service_version</code> —
+ # - <code>:version</code> —
# The service version. Only used if <code>api_method</code> is a
# <code>String</code>. Defaults to <code>'v1'</code>.
# - <code>:parser</code> —
# The parser for the response.
# - <code>:authorization</code> —
# The authorization mechanism for the response. Used only if
- # <code>:signed</code> is <code>true</code>.
- # - <code>:signed</code> —
- # <code>true</code> if the request must be signed, <code>false</code>
- # otherwise. Defaults to <code>true</code>.
+ # <code>:authenticated</code> is <code>true</code>.
+ # - <code>:authenticated</code> —
+ # <code>true</code> if the request must be signed or otherwise
+ # authenticated, <code>false</code>
+ # otherwise. Defaults to <code>true</code> if an authorization
+ # mechanism has been set, <code>false</code> otherwise.
#
# @return [Array] The generated request.
+ #
+ # @example
+ # request = client.generate_request(
+ # 'chili.activities.list',
+ # {'scope' => '@self', 'userId' => '@me', 'alt' => 'json'}
+ # )
+ # method, uri, headers, body = request
def generate_request(
api_method, parameters={}, body='', headers=[], options={})
options={
- :signed => true,
:parser => self.parser,
- :service_version => 'v1',
+ :version => 'v1',
:authorization => self.authorization
}.merge(options)
+ # The default value for the :authenticated option depends on whether an
+ # authorization mechanism has been set.
+ if options[:authorization]
+ options = {:authenticated => true}.merge(options)
+ else
+ options = {:authenticated => false}.merge(options)
+ end
if api_method.kind_of?(String) || api_method.kind_of?(Symbol)
+ api_method = api_method.to_s
+ # This method of guessing the API is unreliable. This will fail for
+ # APIs where the first segment of the RPC name does not match the
+ # service name. However, this is a fallback mechanism anyway.
+ # Developers should be passing in a reference to the method, rather
+ # than passing in a string or symbol. This should raise an error
+ # in the case of a mismatch.
+ api = api_method[/^([^.]+)\./, 1]
api_method = self.discovered_method(
- api_method.to_s, options[:service_version]
+ api_method, api, options[:version]
)
- elsif !api_method.kind_of?(::Google::APIClient::Service)
+ elsif !api_method.kind_of?(::Google::APIClient::Method)
raise TypeError,
- "Expected String, Symbol, or Google::APIClient::Service, " +
+ "Expected String, Symbol, or Google::APIClient::Method, " +
"got #{api_method.class}."
end
unless api_method
- raise ArgumentError, "API method does not exist."
+ raise ArgumentError, "API method could not be found."
end
request = api_method.generate_request(parameters, body, headers)
- if options[:signed]
- request = self.sign_request(request, options[:authorization])
+ if options[:authenticated]
+ request = self.generate_authenticated_request(:request => request)
end
return request
end
# The method object or the RPC name of the method being executed.
# @param [Hash, Array] parameters
# The parameters to send to the method.
- # @param [String] The body of the request.
+ # @param [String] body The body of the request.
# @param [Hash, Array] headers The HTTP headers for the request.
# @param [Hash] options
# The configuration parameters for the request.
- # - <code>:service_version</code> —
+ # - <code>:version</code> —
# The service version. Only used if <code>api_method</code> is a
# <code>String</code>. Defaults to <code>'v1'</code>.
# - <code>:adapter</code> —
# The parser for the response.
# - <code>:authorization</code> —
# The authorization mechanism for the response. Used only if
- # <code>:signed</code> is <code>true</code>.
- # - <code>:signed</code> —
- # <code>true</code> if the request must be signed, <code>false</code>
+ # <code>:authenticated</code> is <code>true</code>.
+ # - <code>:authenticated</code> —
+ # <code>true</code> if the request must be signed or otherwise
+ # authenticated, <code>false</code>
# otherwise. Defaults to <code>true</code>.
#
# @return [Array] The response from the API.
+ #
+ # @example
+ # response = client.execute(
+ # 'chili.activities.list',
+ # {'scope' => '@self', 'userId' => '@me', 'alt' => 'json'}
+ # )
+ # status, headers, body = response
def execute(api_method, parameters={}, body='', headers=[], options={})
request = self.generate_request(
api_method, parameters, body, headers, options
#
# @return [Array] The response from the server.
def transmit_request(request, adapter=self.http_adapter)
- ::HTTPAdapter.transmit(request, adapter)
+ if self.user_agent != nil
+ # If there's no User-Agent header, set one.
+ method, uri, headers, body = request
+ unless headers.kind_of?(Enumerable)
+ # We need to use some Enumerable methods, relying on the presence of
+ # the #each method.
+ class <<headers
+ include Enumerable
+ end
+ end
+ if self.user_agent.kind_of?(String)
+ unless headers.any? { |k, v| k.downcase == 'User-Agent'.downcase }
+ headers = headers.to_a.insert(0, ['User-Agent', self.user_agent])
+ end
+ elsif self.user_agent != nil
+ raise TypeError,
+ "Expected User-Agent to be String, got #{self.user_agent.class}"
+ end
+ end
+ adapter.transmit([method, uri, headers, body])
end
##
# Signs a request using the current authorization mechanism.
#
- # @param [Array] request The request to sign.
- # @param [#generate_authenticated_request] authorization
- # The authorization mechanism.
+ # @param [Hash] options The options to pass through.
#
- # @return [Array] The signed request.
- def sign_request(request, authorization=self.authorization)
- return authorization.generate_authenticated_request(
- :request => request
- )
+ # @return [Array] The signed or otherwise authenticated request.
+ def generate_authenticated_request(options={})
+ return authorization.generate_authenticated_request(options)
end
end
end