[CHEF-3715] rename files checksum_cache -> digester

1 files changed, 73 insertions, 0 deletions

diff --git a/lib/chef/digester.rb b/lib/chef/digester.rb
new file mode 100644
index 0000000000..669ff8b8a5
--- /dev/null
+++ b/lib/chef/digester.rb
@@ -0,0 +1,73 @@
+#
+# Author:: Adam Jacob (<adam@opscode.com>)
+# Author:: Daniel DeLeo (<dan@kallistec.com>)
+# Copyright:: Copyright (c) 2009 Opscode, Inc.
+# Copyright:: Copyright (c) 2009 Daniel DeLeo
+# License:: Apache License, Version 2.0
+#
+# 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 'digest'
+
+class Chef
+  class Digester
+
+    def self.instance
+      @instance ||= new
+    end
+
+    def self.checksum_for_file(*args)
+      instance.checksum_for_file(*args)
+    end
+
+    def validate_checksum(*args)
+      self.class.validate_checksum(*args)
+    end
+
+    def checksum_for_file(file)
+      generate_checksum(file)
+    end
+
+    def generate_checksum(file)
+      checksum_file(file, Digest::SHA256.new)
+    end
+
+    def self.generate_md5_checksum_for_file(*args)
+      instance.generate_md5_checksum_for_file(*args)
+    end
+
+    def generate_md5_checksum_for_file(file)
+      checksum_file(file, Digest::MD5.new)
+    end
+
+    def generate_md5_checksum(io)
+      checksum_io(io, Digest::MD5.new)
+    end
+
+    private
+
+    def checksum_file(file, digest)
+      File.open(file, 'rb') { |f| checksum_io(f, digest) }
+    end
+
+    def checksum_io(io, digest)
+      while chunk = io.read(1024 * 8)
+        digest.update(chunk)
+      end
+      digest.hexdigest
+    end
+
+  end
+end
+