Allow the setting of safe mode globally on the Connection,

DB, and Collection levels. The safe mode setting will
automatically be inherited down the hierarchy Connection ->
DB -> Collection -> (insert, update, remove). This default
can be overridden at any time. Connection#safe, DB#safe, and
Collection#safe will yield the current default value.

lib/mongo/collection.rb

@@ -21,13 +21,18 @@ module Mongo
   # A named collection of documents in a database.
   class Collection
 
-    attr_reader :db, :name, :pk_factory, :hint
+    attr_reader :db, :name, :pk_factory, :hint, :safe
 
     # Initialize a collection object.
     #
     # @param [DB] db a MongoDB database instance.
     # @param [String, Symbol] name the name of the collection.
     #
+    # @option options [Boolean, Hash] :safe (false) Set the default safe-mode options
+    #   for insert, update, and remove method called on this Collection instance. If no
+    #   value is provided, the default value set on this instance's DB will be used. This
+    #   default can be overridden for any invocation of insert, update, or remove.
+    #
     # @raise [InvalidNSName]
     #   if collection name is empty, contains '$', or starts or ends with '.'
     #
@@ -37,7 +42,7 @@ class Collection
     # @return [Collection]
     #
     # @core collections constructor_details
-    def initialize(db, name, pk_factory=nil)
+    def initialize(db, name, pk_factory=nil, options={})
       case name
       when Symbol, String
       else
@@ -60,6 +65,7 @@ def initialize(db, name, pk_factory=nil)
       @connection = @db.connection
       @logger     = @connection.logger
       @pk_factory = pk_factory || BSON::ObjectId
+      @safe       = options.has_key?(:safe) ? options[:safe] : @db.safe
       @hint = nil
     end
 
@@ -245,16 +251,19 @@ def save(doc, opts={})
     # @option opts [Boolean, Hash] :safe (+false+)
     #   run the operation in safe mode, which run a getlasterror command on the
     #   database to report any assertion. In addition, a hash can be provided to
-    #   run an fsync and/or wait for replication of the insert (>= 1.5.1). See the options
-    #   for DB#error.
+    #   run an fsync and/or wait for replication of the insert (>= 1.5.1). Safe
+    #   options provided here will override any safe options set on this collection,
+    #   its database object, or the current connection. See the options on
+    #   for DB#get_last_error.
     #
     # @see DB#remove for options that can be passed to :safe.
     #
     # @core insert insert-instance_method
     def insert(doc_or_docs, options={})
       doc_or_docs = [doc_or_docs] unless doc_or_docs.is_a?(Array)
       doc_or_docs.collect! { |doc| @pk_factory.create_pk(doc) }
-      result = insert_documents(doc_or_docs, @name, true, options[:safe])
+      safe = options.has_key?(:safe) ? options[:safe] : @safe
+      result = insert_documents(doc_or_docs, @name, true, safe)
       result.size > 1 ? result : result.first
     end
     alias_method :<<, :insert
@@ -265,10 +274,11 @@ def insert(doc_or_docs, options={})
     #   If specified, only matching documents will be removed.
     #
     # @option opts [Boolean, Hash] :safe (+false+)
-    #   run the operation in safe mode, which run a getlasterror command on the
+    #   run the operation in safe mode, which will run a getlasterror command on the
     #   database to report any assertion. In addition, a hash can be provided to
-    #   run an fsync and/or wait for replication of the remove (>= 1.5.1). See the options
-    #   for DB#get_last_error.
+    #   run an fsync and/or wait for replication of the remove (>= 1.5.1). Safe
+    #   options provided here will override any safe options set on this collection,
+    #   its database, or the current connection. See the options for DB#get_last_error for more details.
     #
     # @example remove all documents from the 'users' collection:
     #   users.remove
@@ -287,14 +297,15 @@ def insert(doc_or_docs, options={})
     # @core remove remove-instance_method
     def remove(selector={}, opts={})
       # Initial byte is 0.
+      safe = opts.has_key?(:safe) ? opts[:safe] : @safe
       message = BSON::ByteBuffer.new("\0\0\0\0")
       BSON::BSON_RUBY.serialize_cstr(message, "#{@db.name}.#{@name}")
       message.put_int(0)
       message.put_binary(BSON::BSON_CODER.serialize(selector, false, true).to_s)
 
       @logger.debug("MONGODB #{@db.name}['#{@name}'].remove(#{selector.inspect})") if @logger
-      if opts[:safe]
-        @connection.send_message_with_safe_check(Mongo::Constants::OP_DELETE, message, @db.name, nil, opts[:safe])
+      if safe
+        @connection.send_message_with_safe_check(Mongo::Constants::OP_DELETE, message, @db.name, nil, safe)
         # the return value of send_message_with_safe_check isn't actually meaningful --
         # only the fact that it didn't raise an error is -- so just return true
         true
@@ -320,11 +331,14 @@ def remove(selector={}, opts={})
     # @option opts [Boolean] :safe (+false+) 
     #   If true, check that the save succeeded. OperationFailure
     #   will be raised on an error. Note that a safe check requires an extra
-    #   round-trip to the database.
+    #   round-trip to the database. Safe options provided here will override any safe
+    #   options set on this collection, its database object, or the current collection.
+    #   See the options for DB#get_last_error for details.
     #
     # @core update update-instance_method
     def update(selector, document, options={})
       # Initial byte is 0.
+      safe = options.has_key?(:safe) ? options[:safe] : @safe
       message = BSON::ByteBuffer.new("\0\0\0\0")
       BSON::BSON_RUBY.serialize_cstr(message, "#{@db.name}.#{@name}")
       update_options  = 0
@@ -334,8 +348,8 @@ def update(selector, document, options={})
       message.put_binary(BSON::BSON_CODER.serialize(selector, false, true).to_s)
       message.put_binary(BSON::BSON_CODER.serialize(document, false, true).to_s)
       @logger.debug("MONGODB #{@db.name}['#{@name}'].update(#{selector.inspect}, #{document.inspect})") if @logger
-      if options[:safe]
-        @connection.send_message_with_safe_check(Mongo::Constants::OP_UPDATE, message, @db.name, nil, options[:safe])
+      if safe
+        @connection.send_message_with_safe_check(Mongo::Constants::OP_UPDATE, message, @db.name, nil, safe)
       else
         @connection.send_message(Mongo::Constants::OP_UPDATE, message, nil)
       end

lib/mongo/connection.rb

@@ -38,7 +38,8 @@ class Connection
     MONGODB_URI_MATCHER = /(([-_.\w\d]+):([-_\w\d]+)@)?([-.\w\d]+)(:([\w\d]+))?(\/([-\d\w]+))?/
     MONGODB_URI_SPEC = "mongodb://[username:password@]host1[:port1][,host2[:port2],...[,hostN[:portN]]][/database]"
 
-    attr_reader :logger, :size, :host, :port, :nodes, :auths, :sockets, :checked_out, :primary, :secondaries, :arbiters
+    attr_reader :logger, :size, :host, :port, :nodes, :auths, :sockets, :checked_out, :primary, :secondaries, :arbiters,
+      :safe
 
     # Counter for generating unique request ids.
     @@current_request_id = 0
@@ -61,6 +62,10 @@ class Connection
     # @param [String, Hash] host.
     # @param [Integer] port specify a port number here if only one host is being specified.
     #
+    # @option options [Boolean, Hash] :safe (false) Set the default safe-mode options
+    #   propogated to DB objects instantiated off of this Connection. This
+    #   default can be overridden upon instantiation of any DB by explicity setting a :safe value
+    #   on initialization.
     # @option options [Boolean] :slave_ok (false) Must be set to +true+ when connecting
     #   to a single, slave node.
     # @option options [Logger, #debug] :logger (nil) Logger instance to receive driver operation log.
@@ -114,6 +119,9 @@ def initialize(host=nil, port=nil, options={})
       # Mutex for synchronizing pool access
       @connection_mutex = Mutex.new
 
+      # Global safe option. This is false by default.
+      @safe = options[:safe] || false
+
       # Create a mutex when a new key, in this case a socket,
       # is added to the hash.
       @safe_mutexes = Hash.new { |h, k| h[k] = Mutex.new }
@@ -312,7 +320,7 @@ def db(db_name, options={})
     #
     # @core databases []-instance_method
     def [](db_name)
-      DB.new(db_name, self)
+      DB.new(db_name, self, :safe => @safe)
     end
 
     # Drop a database.

lib/mongo/db.rb

@@ -45,8 +45,8 @@ class DB
     # Returns the value of the +strict+ flag.
     def strict?; @strict; end
 
-    # The name of the database.
-    attr_reader :name
+    # The name of the database and the local safe option.
+    attr_reader :name, :safe
 
     # The Mongo::Connection instance connecting to the MongoDB server.
     attr_reader :connection
@@ -65,12 +65,19 @@ def strict?; @strict; end
     #   fields the factory wishes to inject. (NOTE: if the object already has a primary key,
     #   the factory should not inject a new key).
     #
+    # @option options [Boolean, Hash] :safe (false) Set the default safe-mode options
+    #   propogated to Collection objects instantiated off of this DB. If no
+    #   value is provided, the default value set on this instance's Connection object will be used. This
+    #   default can be overridden upon instantiation of any collection by explicity setting a :safe value
+    #   on initialization
+    #
     # @core databases constructor_details
     def initialize(db_name, connection, options={})
       @name       = Mongo::Support.validate_db_name(db_name)
       @connection = connection
       @strict     = options[:strict]
       @pk_factory = options[:pk]
+      @safe       = options.has_key?(:safe) ? options[:safe] : @connection.safe
     end
 
     # Authenticate with the given username and password. Note that mongod
@@ -259,9 +266,13 @@ def create_collection(name, options={})
     # @raise [MongoDBError] if collection does not already exist and we're in +strict+ mode.
     #
     # @return [Mongo::Collection]
-    def collection(name)
-      return Collection.new(self, name, @pk_factory) if !strict? || collection_names.include?(name)
-      raise Mongo::MongoDBError, "Collection #{name} doesn't exist. Currently in strict mode."
+    def collection(name, options={})
+      if strict? && !collection_names.include?(name)
+        raise Mongo::MongoDBError, "Collection #{name} doesn't exist. Currently in strict mode."
+      else
+        options[:safe] = options.has_key?(:safe) ? options[:safe] : @safe
+        Collection.new(self, name, @pk_factory, options)
+      end
     end
     alias_method :[], :collection
 

test/safe_test.rb

@@ -0,0 +1,42 @@
+require './test/test_helper'
+include Mongo
+
+class SafeTest < Test::Unit::TestCase
+  context "Safe tests: " do
+    setup do
+      @con = standard_connection(:safe => {:w => 1})
+      @db  = @con[MONGO_TEST_DB]
+      @col = @db['test-safe']
+      @col.create_index([[:a, 1]], :unique => true)
+      @col.remove
+    end
+
+    should "propogate safe option on insert" do
+      @col.insert({:a => 1})
+
+      assert_raise_error(OperationFailure, "duplicate key") do
+        @col.insert({:a => 1})
+      end
+    end
+
+    should "allow safe override on insert" do
+      @col.insert({:a => 1})
+      @col.insert({:a => 1}, :safe => false)
+    end
+
+    should "propogate safe option on update" do
+      @col.insert({:a => 1})
+      @col.insert({:a => 2})
+
+      assert_raise_error(OperationFailure, "duplicate key") do
+        @col.update({:a => 2}, {:a => 1})
+      end
+    end
+
+    should "allow safe override on update" do
+      @col.insert({:a => 1})
+      @col.insert({:a => 2})
+      @col.update({:a => 2}, {:a => 1}, :safe => false)
+    end
+  end
+end

test/unit/db_test.rb

@@ -16,7 +16,9 @@ def insert_message(db, documents)
     context "DB commands" do
       setup do
         @conn = stub()
+        @conn.stubs(:safe)
         @db   = DB.new("testing", @conn)
+        @db.stubs(:safe)
         @collection = mock()
         @db.stubs(:system_command_collection).returns(@collection)
       end

test/unit/grid_test.rb

@@ -5,12 +5,14 @@ class GridTest < Test::Unit::TestCase
   context "GridFS: " do
     setup do
       @conn   = stub()
+      @conn.stubs(:safe)
       @db     = DB.new("testing", @conn)
       @files  = mock()
       @chunks = mock()
 
       @db.expects(:[]).with('fs.files').returns(@files)
       @db.expects(:[]).with('fs.chunks').returns(@chunks)
+      @db.stubs(:safe)
     end
 
     context "Grid classe with standard connections" do