Working on adding checksum support to design documents to handle updates

lib/couchrest/model/support/couchrest_database.rb

@@ -0,0 +1,15 @@
+
+CouchRest::Database.class_eval do
+
+  alias :delete_orig! :delete!
+  def delete!
+    clear_model_fresh_cache
+    delete_orig!
+  end
+
+  # If the database is deleted, ensure that the design docs will be refreshed.
+  def clear_model_fresh_cache
+    ::CouchRest::Model::Base.subclasses.each{|klass| klass.req_design_doc_refresh if klass.respond_to?(:req_design_doc_refresh)}
+  end
+
+end

lib/couchrest/model/support/couchrest_design.rb

@@ -0,0 +1,24 @@
+
+CouchRest::Design.class_eval do
+
+  # Calculate a checksum of the Design document. Used for ensuring the latest
+  # version has been sent to the database.
+  #
+  # This will generate an flatterned, ordered array of all the elements of the
+  # design document, convert to string then generate an MD5 Hash. This should
+  # result in a consisitent Hash accross all platforms.
+  #
+  def checksum
+    # create a copy of basic elements
+    base = self.dup
+    base.delete('_id')
+    base.delete('_rev')
+    result = nil
+    flatten =
+      lambda{|v|
+        v.is_a?(Hash) ? v.flatten.map{|v| flatten.call(v)}.flatten : v
+      }
+    Digest::MD5.hexdigest(flatten.call(base).sort.join(''))
+  end
+
+end