google-auth-library-ruby/lib/googleauth/credentials.rb

395 lines
14 KiB
Ruby

# Copyright 2017, Google Inc.
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
# * Redistributions in binary form must reproduce the above
# copyright notice, this list of conditions and the following disclaimer
# in the documentation and/or other materials provided with the
# distribution.
# * Neither the name of Google Inc. nor the names of its
# contributors may be used to endorse or promote products derived from
# this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
require "forwardable"
require "json"
require "signet/oauth_2/client"
require "googleauth/credentials_loader"
module Google
module Auth
##
# Credentials is responsible for representing the authentication when connecting to an API. This
# class is also intended to be inherited by API-specific classes.
class Credentials
##
# The default token credential URI to be used when none is provided during initialization.
TOKEN_CREDENTIAL_URI = "https://oauth2.googleapis.com/token".freeze
##
# The default target audience ID to be used when none is provided during initialization.
AUDIENCE = "https://oauth2.googleapis.com/token".freeze
##
# The default token credential URI to be used when none is provided during initialization.
# The URI is the authorization server's HTTP endpoint capable of issuing tokens and
# refreshing expired tokens.
#
# @return [String]
#
def self.token_credential_uri
return @token_credential_uri unless @token_credential_uri.nil?
const_get :TOKEN_CREDENTIAL_URI if const_defined? :TOKEN_CREDENTIAL_URI
end
##
# Set the default token credential URI to be used when none is provided during initialization.
#
# @param [String] new_token_credential_uri
# @return [String]
#
def self.token_credential_uri= new_token_credential_uri
@token_credential_uri = new_token_credential_uri
end
##
# The default target audience ID to be used when none is provided during initialization.
# Used only by the assertion grant type.
#
# @return [String]
#
def self.audience
return @audience unless @audience.nil?
const_get :AUDIENCE if const_defined? :AUDIENCE
end
##
# Sets the default target audience ID to be used when none is provided during initialization.
#
# @param [String] new_audience
# @return [String]
#
def self.audience= new_audience
@audience = new_audience
end
##
# The default scope to be used when none is provided during initialization.
# A scope is an access range defined by the authorization server.
# The scope can be a single value or a list of values.
#
# @return [String, Array<String>]
#
def self.scope
return @scope unless @scope.nil?
tmp_scope = []
# Pull in values is the SCOPE constant exists.
tmp_scope << const_get(:SCOPE) if const_defined? :SCOPE
tmp_scope.flatten.uniq
end
##
# Sets the default scope to be used when none is provided during initialization.
#
# @param [String, Array<String>] new_scope
# @return [String, Array<String>]
#
def self.scope= new_scope
new_scope = Array new_scope unless new_scope.nil?
@scope = new_scope
end
##
# The environment variables to search for credentials. Values can either be a file path to the
# credentials file, or the JSON contents of the credentials file.
#
# @return [Array<String>]
#
def self.env_vars
return @env_vars unless @env_vars.nil?
# Pull values when PATH_ENV_VARS or JSON_ENV_VARS constants exists.
tmp_env_vars = []
tmp_env_vars << const_get(:PATH_ENV_VARS) if const_defined? :PATH_ENV_VARS
tmp_env_vars << const_get(:JSON_ENV_VARS) if const_defined? :JSON_ENV_VARS
tmp_env_vars.flatten.uniq
end
##
# Sets the environment variables to search for credentials.
#
# @param [Array<String>] new_env_vars
# @return [Array<String>]
#
def self.env_vars= new_env_vars
new_env_vars = Array new_env_vars unless new_env_vars.nil?
@env_vars = new_env_vars
end
##
# The file paths to search for credentials files.
#
# @return [Array<String>]
#
def self.paths
return @paths unless @paths.nil?
tmp_paths = []
# Pull in values is the DEFAULT_PATHS constant exists.
tmp_paths << const_get(:DEFAULT_PATHS) if const_defined? :DEFAULT_PATHS
tmp_paths.flatten.uniq
end
##
# Set the file paths to search for credentials files.
#
# @param [Array<String>] new_paths
# @return [Array<String>]
#
def self.paths= new_paths
new_paths = Array new_paths unless new_paths.nil?
@paths = new_paths
end
##
# The Signet::OAuth2::Client object the Credentials instance is using.
#
# @return [Signet::OAuth2::Client]
#
attr_accessor :client
##
# Identifier for the project the client is authenticating with.
#
# @return [String]
#
attr_reader :project_id
##
# Identifier for a separate project used for billing/quota, if any.
#
# @return [String,nil]
#
attr_reader :quota_project_id
# @private Delegate client methods to the client object.
extend Forwardable
##
# @!attribute [r] token_credential_uri
# @return [String] The token credential URI. The URI is the authorization server's HTTP
# endpoint capable of issuing tokens and refreshing expired tokens.
#
# @!attribute [r] audience
# @return [String] The target audience ID when issuing assertions. Used only by the
# assertion grant type.
#
# @!attribute [r] scope
# @return [String, Array<String>] The scope for this client. A scope is an access range
# defined by the authorization server. The scope can be a single value or a list of values.
#
# @!attribute [r] issuer
# @return [String] The issuer ID associated with this client.
#
# @!attribute [r] signing_key
# @return [String, OpenSSL::PKey] The signing key associated with this client.
#
# @!attribute [r] updater_proc
# @return [Proc] Returns a reference to the {Signet::OAuth2::Client#apply} method,
# suitable for passing as a closure.
#
def_delegators :@client,
:token_credential_uri, :audience,
:scope, :issuer, :signing_key, :updater_proc
##
# Creates a new Credentials instance with the provided auth credentials, and with the default
# values configured on the class.
#
# @param [String, Hash, Signet::OAuth2::Client] keyfile
# The keyfile can be provided as one of the following:
#
# * The path to a JSON keyfile (as a +String+)
# * The contents of a JSON keyfile (as a +Hash+)
# * A +Signet::OAuth2::Client+ object
# @param [Hash] options
# The options for configuring the credentials instance. The following is supported:
#
# * +:scope+ - the scope for the client
# * +"project_id"+ (and optionally +"project"+) - the project identifier for the client
# * +:connection_builder+ - the connection builder to use for the client
# * +:default_connection+ - the default connection to use for the client
#
def initialize keyfile, options = {}
verify_keyfile_provided! keyfile
@project_id = options["project_id"] || options["project"]
@quota_project_id = options["quota_project_id"]
if keyfile.is_a? Signet::OAuth2::Client
update_from_signet keyfile
elsif keyfile.is_a? Hash
update_from_hash keyfile, options
else
update_from_filepath keyfile, options
end
CredentialsLoader.warn_if_cloud_sdk_credentials @client.client_id
@project_id ||= CredentialsLoader.load_gcloud_project_id
@client.fetch_access_token!
@env_vars = nil
@paths = nil
@scope = nil
end
##
# Creates a new Credentials instance with auth credentials acquired by searching the
# environment variables and paths configured on the class, and with the default values
# configured on the class.
#
# The auth credentials are searched for in the following order:
#
# 1. configured environment variables (see {Credentials.env_vars})
# 2. configured default file paths (see {Credentials.paths})
# 3. application default (see {Google::Auth.get_application_default})
#
# @param [Hash] options
# The options for configuring the credentials instance. The following is supported:
#
# * +:scope+ - the scope for the client
# * +"project_id"+ (and optionally +"project"+) - the project identifier for the client
# * +:connection_builder+ - the connection builder to use for the client
# * +:default_connection+ - the default connection to use for the client
#
# @return [Credentials]
#
def self.default options = {}
# First try to find keyfile file or json from environment variables.
client = from_env_vars options
# Second try to find keyfile file from known file paths.
client ||= from_default_paths options
# Finally get instantiated client from Google::Auth
client ||= from_application_default options
client
end
##
# @private Lookup Credentials from environment variables.
def self.from_env_vars options
env_vars.each do |env_var|
str = ENV[env_var]
next if str.nil?
return new str, options if ::File.file? str
return new ::JSON.parse(str), options rescue nil
end
nil
end
##
# @private Lookup Credentials from default file paths.
def self.from_default_paths options
paths
.select { |p| ::File.file? p }
.each do |file|
return new file, options
end
nil
end
##
# @private Lookup Credentials using Google::Auth.get_application_default.
def self.from_application_default options
scope = options[:scope] || self.scope
client = Google::Auth.get_application_default scope
new client, options
end
private_class_method :from_env_vars,
:from_default_paths,
:from_application_default
protected
# Verify that the keyfile argument is provided.
def verify_keyfile_provided! keyfile
return unless keyfile.nil?
raise "The keyfile passed to Google::Auth::Credentials.new was nil."
end
# Verify that the keyfile argument is a file.
def verify_keyfile_exists! keyfile
exists = ::File.file? keyfile
raise "The keyfile '#{keyfile}' is not a valid file." unless exists
end
# Initializes the Signet client.
def init_client keyfile, connection_options = {}
client_opts = client_options keyfile
Signet::OAuth2::Client.new(client_opts)
.configure_connection(connection_options)
end
# returns a new Hash with string keys instead of symbol keys.
def stringify_hash_keys hash
Hash[hash.map { |k, v| [k.to_s, v] }]
end
def client_options options
# Keyfile options have higher priority over constructor defaults
options["token_credential_uri"] ||= self.class.token_credential_uri
options["audience"] ||= self.class.audience
options["scope"] ||= self.class.scope
# client options for initializing signet client
{ token_credential_uri: options["token_credential_uri"],
audience: options["audience"],
scope: Array(options["scope"]),
issuer: options["client_email"],
signing_key: OpenSSL::PKey::RSA.new(options["private_key"]) }
end
def update_from_signet client
@project_id ||= client.project_id if client.respond_to? :project_id
@quota_project_id ||= client.quota_project_id if client.respond_to? :quota_project_id
@client = client
end
def update_from_hash hash, options
hash = stringify_hash_keys hash
hash["scope"] ||= options[:scope]
@project_id ||= (hash["project_id"] || hash["project"])
@quota_project_id ||= hash["quota_project_id"]
@client = init_client hash, options
end
def update_from_filepath path, options
verify_keyfile_exists! path
json = JSON.parse ::File.read(path)
json["scope"] ||= options[:scope]
@project_id ||= (json["project_id"] || json["project"])
@quota_project_id ||= json["quota_project_id"]
@client = init_client json, options
end
end
end
end