rename collection

lib/mongo/collection.rb

@@ -192,6 +192,35 @@ EOS
                                    }))["result"]
         end
 
+        # Rename this collection.
+        #
+        # If operating in auth mode, client must be authorized as an admin to
+        # perform this operation. Raises an error if +new_name+ is an invalid
+        # collection name.
+        #
+        # :new_name :: new name for this collection
+        def rename(new_name)
+          case new_name
+          when Symbol, String
+          else
+            raise RuntimeError, "new_name must be a string or symbol"
+          end
+
+          new_name = new_name.to_s
+
+          if new_name.empty? or new_name.include? ".."
+            raise RuntimeError, "collection names cannot be empty"
+          end
+          if new_name.include? "$"
+            raise RuntimeError, "collection names must not contain '$'"
+          end
+          if new_name.match(/^\./) or new_name.match(/\.$/)
+            raise RuntimeError, "collection names must not start or end with '.'"
+          end
+
+          @db.rename_collection(@name, new_name)
+        end
+
         # Get information on the indexes for the collection +collection_name+.
         # Returns a hash where the keys are index names (as returned by
         # Collection#create_index and the values are lists of [key, direction]

lib/mongo/cursor.rb

@@ -31,8 +31,8 @@ module XGen
 
         attr_reader :db, :collection, :query
 
-        def initialize(db, collection, query)
-          @db, @collection, @query = db, collection, query
+        def initialize(db, collection, query, admin=false)
+          @db, @collection, @query, @admin = db, collection, query, admin
           @num_to_return = @query.number_to_return || 0
           @cache = []
           @closed = false
@@ -194,7 +194,7 @@ module XGen
         def refill_via_get_more
           send_query_if_needed
           return if @cursor_id == 0
-          @db.send_to_db(GetMoreMessage.new(@db.name, @collection.name, @cursor_id))
+          @db.send_to_db(GetMoreMessage.new(@admin ? 'admin' : @db.name, @collection.name, @cursor_id))
           read_all
         end
 
@@ -212,7 +212,7 @@ module XGen
         def send_query_if_needed
           # Run query first time we request an object from the wire
           unless @query_run
-            @db.send_query_message(QueryMessage.new(@db.name, @collection.name, @query))
+            @db.send_query_message(QueryMessage.new(@admin ? 'admin' : @db.name, @collection.name, @query))
             @query_run = true
             read_all
           end

lib/mongo/db.rb

@@ -340,8 +340,8 @@ module XGen
         # Note that the query gets sent lazily; the cursor calls
         # #send_query_message when needed. If the caller never requests an
         # object from the cursor, the query never gets sent.
-        def query(collection, query)
-          Cursor.new(self, collection, query)
+        def query(collection, query, admin=false)
+          Cursor.new(self, collection, query, admin)
         end
 
         # Used by a Cursor to lazily send the query to the database.
@@ -416,6 +416,16 @@ module XGen
           raise "Error with eval command: #{doc.inspect}"
         end
 
+        # Rename collection +from+ to +to+. Meant to be called by
+        # Collection#rename.
+        def rename_collection(from, to)
+          oh = OrderedHash.new
+          oh[:renameCollection] = "#{@name}.#{from}"
+          oh[:to] = "#{@name}.#{to}"
+          doc = db_command(oh, true)
+          raise "Error renaming collection: #{doc.inspect}" unless ok?(doc)
+        end
+
         # Drop index +name+ from +collection_name+. Normally called from
         # Collection#drop_index or Collection#drop_indexes.
         def drop_index(collection_name, name)
@@ -511,7 +521,7 @@ module XGen
         # that the "command" key be first.
         #
         # Do not call this. Intended for driver use only.
-        def db_command(selector)
+        def db_command(selector, use_admin_db=false)
           if !selector.kind_of?(OrderedHash)
             if !selector.kind_of?(Hash) || selector.keys.length > 1
               raise "db_command must be given an OrderedHash when there is more than one key"
@@ -520,7 +530,7 @@ module XGen
 
           q = Query.new(selector)
           q.number_to_return = 1
-          query(Collection.new(self, SYSTEM_COMMAND_COLLECTION), q).next_object
+          query(Collection.new(self, SYSTEM_COMMAND_COLLECTION), q, use_admin_db).next_object
         end
 
         private

tests/test_db_api.rb

@@ -713,6 +713,53 @@ class DBAPITest < Test::Unit::TestCase
     @@coll.modify({"hello" => "world"}, {"$inc" => "hello"})
   end
 
+  def test_rename_collection
+    @@db.drop_collection("foo")
+    @@db.drop_collection("bar")
+    a = @@db.collection("foo")
+    b = @@db.collection("bar")
+
+    assert_raise RuntimeError do
+      a.rename(5)
+    end
+    assert_raise RuntimeError do
+      a.rename("")
+    end
+    assert_raise RuntimeError do
+      a.rename("te$t")
+    end
+    assert_raise RuntimeError do
+      a.rename(".test")
+    end
+    assert_raise RuntimeError do
+      a.rename("test.")
+    end
+    assert_raise RuntimeError do
+      a.rename("tes..t")
+    end
+
+    assert_equal 0, a.count()
+    assert_equal 0, b.count()
+
+    a.insert("x" => 1)
+    a.insert("x" => 2)
+
+    assert_equal 2, a.count()
+
+    a.rename("bar")
+
+    assert_equal 0, a.count()
+    assert_equal 2, b.count()
+
+    assert_equal 1, b.find().to_a()[0]["x"]
+    assert_equal 2, b.find().to_a()[1]["x"]
+
+    b.rename(:foo)
+
+    assert_equal 2, a.count()
+    assert_equal 0, b.count()
+  end
+
 # TODO this test fails with error message "Undefed Before end of object"
 # That is a database error. The undefined type may go away.