# 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 'faraday'
require 'multi_json'
require 'compat/multi_json'
require 'stringio'
require 'retriable'
require 'google/api_client/version'
require 'google/api_client/logging'
require 'google/api_client/errors'
require 'google/api_client/environment'
require 'google/api_client/discovery'
require 'google/api_client/request'
require 'google/api_client/reference'
require 'google/api_client/result'
require 'google/api_client/media'
require 'google/api_client/service_account'
require 'google/api_client/batch'
require 'google/api_client/gzip'
require 'google/api_client/client_secrets'
require 'google/api_client/railtie' if defined?(Rails)
module Google
##
# This class manages APIs communication.
class APIClient
include Google::APIClient::Logging
##
# 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:
#
# :two_legged_oauth_1
# :oauth_1
# :oauth_2
#
# @option options [Boolean] :auto_refresh_token (true)
# The setting that controls whether or not the api client attempts to
# refresh authorization when a 401 is hit in #execute. If the token does
# not support it, this option is ignored.
# @option options [String] :application_name
# The name of the application using the client.
# @option options [String] :application_version
# The version number of the application using the client.
# @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.
# @option options [String] :host ("www.googleapis.com")
# The API hostname used by the client. This rarely needs to be changed.
# @option options [String] :port (443)
# The port number used by the client. This rarely needs to be changed.
# @option options [String] :discovery_path ("/discovery/v1")
# The discovery base path. This rarely needs to be changed.
# @option options [String] :ca_file
# Optional set of root certificates to use when validating SSL connections.
# By default, a bundled set of trusted roots will be used.
# @options options[Hash] :faraday_options
# Pass through of options to set on the Faraday connection
def initialize(options={})
logger.debug { "#{self.class} - Initializing client with options #{options}" }
# Normalize key to String to allow indifferent access.
options = options.inject({}) do |accu, (key, value)|
accu[key.to_sym] = value
accu
end
# Almost all API usage will have a host of 'www.googleapis.com'.
self.host = options[:host] || 'www.googleapis.com'
self.port = options[:port] || 443
self.discovery_path = options[:discovery_path] || '/discovery/v1'
# Most developers will want to leave this value alone and use the
# application_name option.
if options[:application_name]
app_name = options[:application_name]
app_version = options[:application_version]
application_string = "#{app_name}/#{app_version || '0.0.0'}"
else
logger.warn { "#{self.class} - Please provide :application_name and :application_version when initializing the client" }
end
proxy = options[:proxy] || Object::ENV["http_proxy"]
self.user_agent = options[:user_agent] || (
"#{application_string} " +
"google-api-ruby-client/#{Google::APIClient::VERSION::STRING} #{ENV::OS_VERSION} (gzip)"
).strip
# The writer method understands a few Symbols and will generate useful
# default authentication mechanisms.
self.authorization =
options.key?(:authorization) ? options[:authorization] : :oauth_2
self.auto_refresh_token = options.fetch(:auto_refresh_token) { true }
self.key = options[:key]
self.user_ip = options[:user_ip]
self.retries = options.fetch(:retries) { 0 }
@discovery_uris = {}
@discovery_documents = {}
@discovered_apis = {}
ca_file = options[:ca_file] || File.expand_path('../../cacerts.pem', __FILE__)
self.connection = Faraday.new do |faraday|
faraday.response :gzip
faraday.options.params_encoder = Faraday::FlatParamsEncoder
faraday.ssl.ca_file = ca_file
faraday.ssl.verify = true
faraday.proxy proxy
faraday.adapter Faraday.default_adapter
if options[:faraday_option].is_a?(Hash)
options[:faraday_option].each_pair do |option, value|
faraday.options.send("#{option}=", value)
end
end
end
return self
end
##
# Returns the authorization mechanism used by the client.
#
# @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
new_authorization = Signet::OAuth1::Client.new(
:temporary_credential_uri =>
'https://www.google.com/accounts/OAuthGetRequestToken',
:authorization_uri =>
'https://www.google.com/accounts/OAuthAuthorizeToken',
:token_credential_uri =>
'https://www.google.com/accounts/OAuthGetAccessToken',
: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
@authorization = new_authorization
return @authorization
end
##
# Default Faraday/HTTP connection.
#
# @return [Faraday::Connection]
attr_accessor :connection
##
# The setting that controls whether or not the api client attempts to
# refresh authorization when a 401 is hit in #execute.
#
# @return [Boolean]
attr_accessor :auto_refresh_token
##
# The application's API key issued by the API console.
#
# @return [String] The API key.
attr_accessor :key
##
# The IP address of the user this request is being performed on behalf of.
#
# @return [String] The user's IP address.
attr_accessor :user_ip
##
# The user agent used by the client.
#
# @return [String]
# The user agent string used in the User-Agent header.
attr_accessor :user_agent
##
# The API hostname used by the client.
#
# @return [String]
# The API hostname. Should almost always be 'www.googleapis.com'.
attr_accessor :host
##
# The port number used by the client.
#
# @return [String]
# The port number. Should almost always be 443.
attr_accessor :port
##
# The base path used by the client for discovery.
#
# @return [String]
# The base path. Should almost always be '/discovery/v1'.
attr_accessor :discovery_path
##
# Number of times to retry on recoverable errors
#
# @return [FixNum]
# Number of retries
attr_accessor :retries
##
# Returns the URI for the directory document.
#
# @return [Addressable::URI] The URI of the directory document.
def directory_uri
return resolve_uri(self.discovery_path + '/apis')
end
##
# Manually registers a URI as a discovery document for a specific version
# of an API.
#
# @param [String, Symbol] api The API name.
# @param [String] version The desired version of the API.
# @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 API name.
# @param [String] version The desired version of the API.
# @return [Addressable::URI] The URI of the discovery document.
def discovery_uri(api, version=nil)
api = api.to_s
version = version || 'v1'
return @discovery_uris["#{api}:#{version}"] ||= (
resolve_uri(
self.discovery_path + '/apis/{api}/{version}/rest',
'api' => api,
'version' => version
)
)
end
##
# Manually registers a pre-loaded discovery document for a specific version
# of an API.
#
# @param [String, Symbol] api The API name.
# @param [String] version The desired version of the API.
# @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}"] =
MultiJson.load(discovery_document)
end
##
# Returns the parsed directory document.
#
# @return [Hash] The parsed JSON from the directory document.
def directory_document
return @directory_document ||= (begin
response = self.execute!(
:http_method => :get,
:uri => self.directory_uri,
:authenticated => false
)
response.data
end)
end
##
# Returns the parsed discovery document.
#
# @param [String, Symbol] api The API name.
# @param [String] version The desired version of the API.
# @return [Hash] The parsed JSON from the discovery document.
def discovery_document(api, version=nil)
api = api.to_s
version = version || 'v1'
return @discovery_documents["#{api}:#{version}"] ||= (begin
response = self.execute!(
:http_method => :get,
:uri => self.discovery_uri(api, version),
:authenticated => false
)
response.data
end)
end
##
# 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
end)
end
##
# Returns the service object for a given service name and service version.
#
# @param [String, Symbol] api The API name.
# @param [String] version The desired version of the API.
#
# @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 #{api.class}."
end
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
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, Symbol] api The API the method is within.
# @param [String] version The desired version of the API.
#
# @return [Google::APIClient::Method] The method object.
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
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
end
##
# Returns the service object with the highest version number.
#
# @note Warning: 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] api The name of the service.
#
# @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 #{api.class}."
end
api = api.to_s
return self.discovered_apis.detect do |a|
a.name == api && a.preferred == true
end
end
##
# Verifies an ID token against a server certificate. Used to ensure that
# an ID token supplied by an untrusted client-side mechanism is valid.
# Raises an error if the token is invalid or missing.
#
# @deprecated Use the google-id-token gem for verifying JWTs
def verify_id_token!
require 'jwt'
require 'openssl'
@certificates ||= {}
if !self.authorization.respond_to?(:id_token)
raise ArgumentError, (
"Current authorization mechanism does not support ID tokens: " +
"#{self.authorization.class.to_s}"
)
elsif !self.authorization.id_token
raise ArgumentError, (
"Could not verify ID token, ID token missing. " +
"Scopes were: #{self.authorization.scope.inspect}"
)
else
check_cached_certs = lambda do
valid = false
for key, cert in @certificates
begin
self.authorization.decoded_id_token(cert.public_key)
valid = true
rescue JWT::DecodeError, Signet::UnsafeOperationError
# Expected exception. Ignore, ID token has not been validated.
end
end
valid
end
if check_cached_certs.call()
return true
end
response = self.execute!(
:http_method => :get,
:uri => 'https://www.googleapis.com/oauth2/v1/certs',
:authenticated => false
)
@certificates.merge!(
Hash[MultiJson.load(response.body).map do |key, cert|
[key, OpenSSL::X509::Certificate.new(cert)]
end]
)
if check_cached_certs.call()
return true
else
raise InvalidIDTokenError,
"Could not verify ID token against any available certificate."
end
end
return nil
end
##
# Generates a request.
#
# @option options [Google::APIClient::Method] :api_method
# The method object or the RPC name of the method being executed.
# @option options [Hash, Array] :parameters
# The parameters to send to the method.
# @option options [Hash, Array] :headers The HTTP headers for the request.
# @option options [String] :body The body of the request.
# @option options [String] :version ("v1")
# The service version. Only used if `api_method` is a `String`.
# @option options [#generate_authenticated_request] :authorization
# The authorization mechanism for the response. Used only if
# `:authenticated` is `true`.
# @option options [TrueClass, FalseClass] :authenticated (true)
# `true` if the request must be signed or somehow
# authenticated, `false` otherwise.
#
# @return [Google::APIClient::Reference] The generated request.
#
# @example
# request = client.generate_request(
# :api_method => 'plus.activities.list',
# :parameters =>
# {'collection' => 'public', 'userId' => 'me'}
# )
def generate_request(options={})
options = {
:api_client => self
}.merge(options)
return Google::APIClient::Request.new(options)
end
##
# Executes a request, wrapping it in a Result object.
#
# @param [Google::APIClient::Request, Hash, Array] params
# Either a Google::APIClient::Request, a Hash, or an Array.
#
# If a Google::APIClient::Request, no other parameters are expected.
#
# If a Hash, the below parameters are handled. If an Array, the
# parameters are assumed to be in the below order:
#
# - (Google::APIClient::Method) api_method:
# The method object or the RPC name of the method being executed.
# - (Hash, Array) parameters:
# The parameters to send to the method.
# - (String) body: The body of the request.
# - (Hash, Array) headers: The HTTP headers for the request.
# - (Hash) options: A set of options for the request, of which:
# - (#generate_authenticated_request) :authorization (default: true) -
# The authorization mechanism for the response. Used only if
# `:authenticated` is `true`.
# - (TrueClass, FalseClass) :authenticated (default: true) -
# `true` if the request must be signed or somehow
# authenticated, `false` otherwise.
# - (TrueClass, FalseClass) :gzip (default: true) -
# `true` if gzip enabled, `false` otherwise.
# - (FixNum) :retries -
# # of times to retry on recoverable errors
#
# @return [Google::APIClient::Result] The result from the API, nil if batch.
#
# @example
# result = client.execute(batch_request)
#
# @example
# plus = client.discovered_api('plus')
# result = client.execute(
# :api_method => plus.activities.list,
# :parameters => {'collection' => 'public', 'userId' => 'me'}
# )
#
# @see Google::APIClient#generate_request
def execute!(*params)
if params.first.kind_of?(Google::APIClient::Request)
request = params.shift
options = params.shift || {}
else
# This block of code allows us to accept multiple parameter passing
# styles, and maintaining some backwards compatibility.
#
# Note: I'm extremely tempted to deprecate this style of execute call.
if params.last.respond_to?(:to_hash) && params.size == 1
options = params.pop
else
options = {}
end
options[:api_method] = params.shift if params.size > 0
options[:parameters] = params.shift if params.size > 0
options[:body] = params.shift if params.size > 0
options[:headers] = params.shift if params.size > 0
options.update(params.shift) if params.size > 0
request = self.generate_request(options)
end
request.headers['User-Agent'] ||= '' + self.user_agent unless self.user_agent.nil?
request.headers['Accept-Encoding'] ||= 'gzip' unless options[:gzip] == false
request.headers['Content-Type'] ||= ''
request.parameters['key'] ||= self.key unless self.key.nil?
request.parameters['userIp'] ||= self.user_ip unless self.user_ip.nil?
connection = options[:connection] || self.connection
request.authorization = options[:authorization] || self.authorization unless options[:authenticated] == false
tries = 1 + (options[:retries] || self.retries)
Retriable.retriable :tries => tries,
:on => [TransmissionError],
:on_retry => client_error_handler(request.authorization),
:interval => lambda {|attempts| (2 ** attempts) + rand} do
result = request.send(connection, true)
case result.status
when 200...300
result
when 301, 302, 303, 307
request = generate_request(request.to_hash.merge({
:uri => result.headers['location'],
:api_method => nil
}))
raise RedirectError.new(result.headers['location'], result)
when 400...500
raise ClientError.new(result.error_message || "A client error has occurred", result)
when 500...600
raise ServerError.new(result.error_message || "A server error has occurred", result)
else
raise TransmissionError.new(result.error_message || "A transmission error has occurred", result)
end
end
end
##
# Same as Google::APIClient#execute!, but does not raise an exception for
# normal API errros.
#
# @see Google::APIClient#execute
def execute(*params)
begin
return self.execute!(*params)
rescue TransmissionError => e
return e.result
end
end
protected
##
# Resolves a URI template against the client's configured base.
#
# @api private
# @param [String, Addressable::URI, Addressable::Template] template
# The template to resolve.
# @param [Hash] mapping The mapping that corresponds to the template.
# @return [Addressable::URI] The expanded URI.
def resolve_uri(template, mapping={})
@base_uri ||= Addressable::URI.new(
:scheme => 'https',
:host => self.host,
:port => self.port
).normalize
template = if template.kind_of?(Addressable::Template)
template.pattern
elsif template.respond_to?(:to_str)
template.to_str
else
raise TypeError,
"Expected String, Addressable::URI, or Addressable::Template, " +
"got #{template.class}."
end
return Addressable::Template.new(@base_uri + template).expand(mapping)
end
##
# Returns on proc for special processing of retries as not all client errors
# are recoverable. Only 401s should be retried and only if the credentials
# are refreshable
#
# @param [#fetch_access_token!] authorization
# OAuth 2 credentials
# @return [Proc]
def client_error_handler(authorization)
can_refresh = authorization.respond_to?(:refresh_token) && auto_refresh_token
Proc.new do |exception, tries|
next unless exception.kind_of?(ClientError)
if exception.result.status == 401 && can_refresh && tries == 1
begin
logger.debug("Attempting refresh of access token & retry of request")
authorization.fetch_access_token!
next
rescue Signet::AuthorizationError
end
end
raise exception
end
end
end
end