Refactor key loading to support PEM + fix issue #62

lib/google/api_client/auth/key_utils.rb

@@ -0,0 +1,93 @@
+# 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.
+
+module Google
+  class APIClient
+    ##
+    # Helper for loading keys from the PKCS12 files downloaded when
+    # setting up service accounts at the APIs Console.
+    #
+    module KeyUtils
+      ##
+      # Loads a key from PKCS12 file, assuming a single private key
+      # is present.
+      #
+      # @param [String] keyfile
+      #    Path of the PKCS12 file to load. If not a path to an actual file,
+      #    assumes the string is the content of the file itself. 
+      # @param [String] passphrase
+      #   Passphrase for unlocking the private key
+      #
+      # @return [OpenSSL::PKey] The private key for signing assertions.
+      def self.load_from_pkcs12(keyfile, passphrase)
+        load_key(keyfile, passphrase) do |content, passphrase| 
+          OpenSSL::PKCS12.new(content, passphrase).key
+        end
+      end
+      
+
+      ##
+      # Loads a key from a PEM file.
+      #
+      # @param [String] keyfile
+      #    Path of the PEM file to load. If not a path to an actual file,
+      #    assumes the string is the content of the file itself. 
+      # @param [String] passphrase
+      #   Passphrase for unlocking the private key
+      #
+      # @return [OpenSSL::PKey] The private key for signing assertions.
+      #
+      def self.load_from_pem(keyfile, passphrase)
+        load_key(keyfile, passphrase) do | content, passphrase|
+          OpenSSL::PKey::RSA.new(content, passphrase)
+        end
+      end
+
+      private
+      
+      ##
+      # Helper for loading keys from file or memory. Accepts a block
+      # to handle the specific file format.
+      #
+      # @param [String] keyfile
+      #    Path of thefile to load. If not a path to an actual file,
+      #    assumes the string is the content of the file itself. 
+      # @param [String] passphrase
+      #   Passphrase for unlocking the private key
+      #
+      # @yield [String, String]
+      #   Key file & passphrase to extract key from
+      # @yieldparam [String] keyfile
+      #   Contents of the file
+      # @yieldparam [String] passphrase
+      #   Passphrase to unlock key
+      # @yieldreturn [OpenSSL::PKey]
+      #   Private key
+      #
+      # @return [OpenSSL::PKey] The private key for signing assertions.
+      def self.load_key(keyfile, passphrase, &block)
+        begin
+          begin
+            content = File.read(keyfile)
+          rescue
+            content = keyfile
+          end
+          block.call(content, passphrase)
+        rescue OpenSSL::OpenSSLError
+          raise ArgumentError.new("Invalid keyfile or passphrase")
+        end        
+      end  
+    end
+  end
+end

lib/google/api_client/auth/pkcs12.rb

@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
+require 'google/api_client/auth/key_utils'
 module Google
   class APIClient
     ##
@@ -30,18 +31,10 @@ module Google
       #   Passphrase for unlocking the private key
       #
       # @return [OpenSSL::PKey] The private key for signing assertions.
+      # @deprecated 
+      #  Use {Google::APIClient::KeyUtils} instead
       def self.load_key(keyfile, passphrase)
-        begin
-          if File.exists?(keyfile)
-            content = File.read(keyfile)
-          else
-            content = keyfile
-          end  
-          pkcs12 = OpenSSL::PKCS12.new(content, passphrase)
-          return pkcs12.key
-        rescue OpenSSL::PKCS12::PKCS12Error
-          raise ArgumentError.new("Invalid keyfile or passphrase")
-        end
+        KeyUtils.load_from_pkcs12(keyfile, passphrase)
       end
     end
   end