lib/google/api_client/auth/storage.rb

   1 # Copyright 2013 Google Inc.
   2 #
   3 # Licensed under the Apache License, Version 2.0 (the "License");
   4 # you may not use this file except in compliance with the License.
   5 # You may obtain a copy of the License at
   6 #
   7 #      http://www.apache.org/licenses/LICENSE-2.0
   8 #
   9 # Unless required by applicable law or agreed to in writing, software
  10 # distributed under the License is distributed on an "AS IS" BASIS,
  11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  12 # See the License for the specific language governing permissions and
  13 # limitations under the License.
  14
  15 require 'signet/oauth_2/client'
  16
  17 module Google
  18   class APIClient
  19     ##
  20     # Represents cached OAuth 2 tokens stored on local disk in a
  21     # JSON serialized file. Meant to resemble the serialized format
  22     # http://google-api-python-client.googlecode.com/hg/docs/epy/oauth2client.file.Storage-class.html
  23     #
  24     class Storage
  25
  26       AUTHORIZATION_URI = 'https://accounts.google.com/o/oauth2/auth'
  27       TOKEN_CREDENTIAL_URI = 'https://accounts.google.com/o/oauth2/token'
  28
  29       # @return [Object] Storage object.
  30       attr_accessor :store
  31
  32       # @return [Signet::OAuth2::Client]
  33       attr_reader :authorization
  34
  35       ##
  36       # Initializes the Storage object.
  37       #
  38       # @params [Object] Storage object
  39       def initialize(store)
  40         @store= store
  41         self.authorize
  42       end
  43
  44       ##
  45       # Write the credentials to the specified store.
  46       #
  47       # @params [Signet::OAuth2::Client] authorization
  48       #    Optional authorization instance. If not provided, the authorization
  49       #    already associated with this instance will be written.
  50       def write_credentials(authorization=nil)
  51         @authorization = authorization if authorization
  52         if @authorization.refresh_token
  53           store.write_credentials(credentials_hash)
  54         end
  55       end
  56
  57       ##
  58       # Loads credentials and authorizes an client.
  59       # @return [Object] Signet::OAuth2::Client or NIL
  60       def authorize
  61         if load_credentials
  62           cached_credentials = load_credentials
  63           @authorization = Signet::OAuth2::Client.new(cached_credentials)
  64           @authorization.issued_at = Time.at(cached_credentials['issued_at'].to_i)
  65           self.refresh_authorization if @authorization.expired?
  66         end
  67       end
  68
  69       ##
  70       # refresh credentials and save them to store
  71       def refresh_authorization
  72         @authorization.refresh!
  73         self.write_credentials
  74       end
  75
  76       private
  77
  78       ##
  79       # Attempt to read in credentials from the specified store.
  80       def load_credentials
  81         store.load_credentials
  82       end
  83
  84       ##
  85       # @return [Hash] with credentials
  86       def credentials_hash
  87         {
  88           :access_token          => @authorization.access_token,
  89           :authorization_uri     => AUTHORIZATION_URI,
  90           :client_id             => @authorization.client_id,
  91           :client_secret         => @authorization.client_secret,
  92           :expires_in            => @authorization.expires_in,
  93           :refresh_token         => @authorization.refresh_token,
  94           :token_credential_uri  => TOKEN_CREDENTIAL_URI,
  95           :issued_at             => @authorization.issued_at.to_i
  96         }
  97       end
  98     end
  99   end
 100 end