Add a small web sample showing incremental authorization & use of APIs

samples/cli/lib/base_cli.rb

@@ -0,0 +1,94 @@
+# Copyright 2016 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 'googleauth'
+require 'googleauth/stores/file_token_store'
+require 'fileutils'
+require 'thor'
+require 'os'
+
+# Base command line module for samples. Provides authorization support,
+# either using application default credentials or user authorization
+# depending on the use case.
+class BaseCli < Thor
+  include Thor::Actions
+
+  OOB_URI = 'urn:ietf:wg:oauth:2.0:oob'
+
+  class_option :user, :type => :string
+  class_option :api_key, :type => :string
+
+  no_commands do
+
+    # Returns the path to the client_secrets.json file.
+    def client_secrets_path
+      return ENV['GOOGLE_CLIENT_SECRETS'] if ENV.has_key?('GOOGLE_CLIENT_SECRETS')
+      return well_known_path_for('client_secrets.json')
+    end
+
+    # Returns the path to the token store.
+    def token_store_path
+      return ENV['GOOGLE_CREDENTIAL_STORE'] if ENV.has_key?('GOOGLE_CREDENTIAL_STORE')
+      return well_known_path_for('credentials.yaml')
+    end
+
+    # Builds a path to a file in $HOME/.config/google (or %APPDATA%/google,
+    # on Windows)
+    def well_known_path_for(file)
+      if OS.windows?
+        File.join(ENV['APPDATA'], 'google', file)
+      else
+        File.join(ENV['HOME'], '.config', 'google', file)
+      end
+    end
+
+    # Returns application credentials for the given scope.
+    def application_credentials_for(scope)
+      Google::Auth.get_application_default(scope)
+    end
+
+    # Returns user credentials for the given scope. Requests authorization
+    # if requrired.
+    def user_credentials_for(scope)
+      FileUtils.mkdir_p(File.dirname(token_store_path))
+
+      if ENV['GOOGLE_CLIENT_ID']
+        client_id = Google::Auth::ClientId.new(ENV['GOOGLE_CLIENT_ID'], ENV['GOOGLE_CLIENT_SECRET'])
+      else
+        client_id = Google::Auth::ClientId.from_file(client_secrets_path)
+      end
+      token_store = Google::Auth::Stores::FileTokenStore.new(:file => token_store_path)
+      authorizer = Google::Auth::UserAuthorizer.new(client_id, scope, token_store)
+
+      user_id = options[:user] || 'default'
+
+      credentials = authorizer.get_credentials(user_id)
+      if credentials.nil?
+        url = authorizer.get_authorization_url(base_url: OOB_URI)
+        say "Open the following URL in your browser and authorize the application."
+        say url
+        code = ask "Enter the authorization code:"
+        credentials = authorizer.get_and_store_credentials_from_code(
+          user_id: user_id, code: code, base_url: OOB_URI)
+      end
+      credentials
+    end
+
+    # Gets the API key of the client
+    def api_key
+      ENV['GOOGLE_API_KEY'] || options[:api_key]
+    end
+
+  end
+end