Started the refactoring work on couchrest.

* A server can have multiple defined available databases set to be used by documents (think DM repos)
* A server can have a default database so documents can easily share the same db connection
* Let a document class have a default database to use
* Give access to a document uri
* extracted some of the document features to a mixin

lib/couchrest/core/document.rb

@@ -14,47 +14,20 @@ module CouchRest
   end
   
   class Document < Response
+    include CouchRest::Mixins::Views
 
     attr_accessor :database
-
-    # alias for self['_id']
-    def id
-      self['_id']
+    @@database = nil
+    
+    # override the CouchRest::Model-wide default_database
+    # This is not a thread safe operation, do not change the model
+    # database at runtime.
+    def self.use_database(db)
+      @@database = db
     end
-
-    # alias for self['_rev']      
-    def rev
-      self['_rev']
-    end
-
-    # returns true if the document has never been saved
-    def new_document?
-      !rev
-    end
-
-    # Saves the document to the db using create or update. Also runs the :save
-    # callbacks. Sets the <tt>_id</tt> and <tt>_rev</tt> fields based on
-    # CouchDB's response.
-    # If <tt>bulk</tt> is <tt>true</tt> (defaults to false) the document is cached for bulk save.
-    def save(bulk = false)
-      raise ArgumentError, "doc.database required for saving" unless database
-      result = database.save_doc self, bulk
-      result['ok']
-    end
-
-    # Deletes the document from the database. Runs the :delete callbacks.
-    # Removes the <tt>_id</tt> and <tt>_rev</tt> fields, preparing the
-    # document to be saved to a new <tt>_id</tt>.
-    # If <tt>bulk</tt> is <tt>true</tt> (defaults to false) the document won't 
-    # actually be deleted from the db until bulk save.
-    def destroy(bulk = false)
-      raise ArgumentError, "doc.database required to destroy" unless database
-      result = database.delete_doc(self, bulk)
-      if result['ok']
-        self['_rev'] = nil
-        self['_id'] = nil
-      end
-      result['ok']
+    
+    def self.database
+      @@database
     end
     
     # copies the document to a new id. If the destination id currently exists, a rev must be provided.
@@ -75,6 +48,23 @@ module CouchRest
       result['ok']
     end
     
+    # Returns the CouchDB uri for the document
+    def uri(append_rev = false)
+      return nil if new_document?
+      couch_uri = "http://#{database.uri}/#{CGI.escape(id)}"
+      if append_rev == true
+        couch_uri << "?rev=#{rev}"
+      elsif append_rev.kind_of?(Integer)
+        couch_uri << "?rev=#{append_rev}"
+      end
+      couch_uri
+    end
+    
+    # Returns the document's database
+    def database
+      @database || self.class.database
+    end
+    
     # saves an attachment directly to couchdb
     def put_attachment(name, file, options={})
       raise ArgumentError, "doc.database required to put_attachment" unless database
@@ -97,6 +87,5 @@ module CouchRest
       result['ok']
     end
   end
-
   
 end

lib/couchrest/core/server.rb

@@ -1,25 +1,62 @@
 module CouchRest
   class Server
-    attr_accessor :uri, :uuid_batch_count
-    def initialize server = 'http://127.0.0.1:5984', uuid_batch_count = 1000
+    attr_accessor :uri, :uuid_batch_count, :available_databases
+    def initialize(server = 'http://127.0.0.1:5984', uuid_batch_count = 1000)
       @uri = server
       @uuid_batch_count = uuid_batch_count
     end
   
-    # List all databases on the server
+    # Lists all "available" databases.
+    # An available database, is a database that was specified
+    # as avaiable by your code.
+    # It allows to define common databases to use and reuse in your code
+    def available_databases
+      @available_databases ||= {}
+    end
+    
+    # Adds a new available database and create it unless it already exists
+    #
+    # Example:
+    #
+    # @couch = CouchRest::Server.new
+    # @couch.define_available_database(:default, "tech-blog")
+    #
+    def define_available_database(reference, db_name, create_unless_exists = true)
+      available_databases[reference.to_sym] = create_unless_exists ? database!(db_name) : database(db_name)
+    end
+  
+    # Checks that a database is set as available
+    #
+    # Example:
+    #
+    # @couch.available_database?(:default)
+    #
+    def available_database?(ref_or_name)
+      ref_or_name.is_a?(Symbol) ? available_databases.keys.include?(ref_or_name) : available_databases.values.map{|db| db.name}.include?(ref_or_name)
+    end
+  
+    def default_database=(name, create_unless_exists = true)
+      define_available_database(:default, name, create_unless_exists = true)
+    end
+    
+    def default_database
+      available_databases[:default]
+    end
+  
+    # Lists all databases on the server
     def databases
       CouchRest.get "#{@uri}/_all_dbs"
     end
   
     # Returns a CouchRest::Database for the given name
-    def database name
+    def database(name)
       CouchRest::Database.new(self, name)
     end
   
     # Creates the database if it doesn't exist
-    def database! name
+    def database!(name)
       create_db(name) rescue nil
-      database name
+      database(name)
     end
   
     # GET the welcome message
@@ -28,9 +65,9 @@ module CouchRest
     end
 
     # Create a database
-    def create_db name
+    def create_db(name)
       CouchRest.put "#{@uri}/#{name}"
-      database name
+      database(name)
     end
 
     # Restart the CouchDB instance
@@ -39,7 +76,7 @@ module CouchRest
     end
 
     # Retrive an unused UUID from CouchDB. Server instances manage caching a list of unused UUIDs.
-    def next_uuid count = @uuid_batch_count
+    def next_uuid(count = @uuid_batch_count)
       @uuids ||= []
       if @uuids.empty?
         @uuids = CouchRest.post("#{@uri}/_uuids?count=#{count}")["uuids"]