feat(session): allow session options to be passed to write cmds

NODE-1088

Author: mbroadst

lib/topologies/server.js

@@ -692,7 +692,8 @@ Server.prototype.command = function(ns, cmd, options, callback) {
     monitoring: typeof options.monitoring === 'boolean' ? options.monitoring : false,
     fullResult: typeof options.fullResult === 'boolean' ? options.fullResult : false,
     requestId: query.requestId,
-    socketTimeout: typeof options.socketTimeout === 'number' ? options.socketTimeout : null
+    socketTimeout: typeof options.socketTimeout === 'number' ? options.socketTimeout : null,
+    session: options.session || null
   };
 
   // Write the operation to the pool

lib/wireprotocol/2_6_support.js

@@ -49,6 +49,7 @@ var executeWrite = function(pool, bson, type, opsField, ns, ops, options, callba
 
   // Options object
   var opts = { command: true };
+  if (typeof options.session !== 'undefined') opts.session = options.session;
   var queryOptions = { checkKeys: false, numberToSkip: 0, numberToReturn: 1 };
   if (type === 'insert') queryOptions.checkKeys = true;
   if (typeof options.checkKeys === 'boolean') queryOptions.checkKeys = options.checkKeys;

lib/wireprotocol/3_2_support.js

@@ -58,6 +58,7 @@ var executeWrite = function(pool, bson, type, opsField, ns, ops, options, callba
 
   // Options object
   var opts = { command: true };
+  if (typeof options.session !== 'undefined') opts.session = options.session;
   var queryOptions = { checkKeys: false, numberToSkip: 0, numberToReturn: 1 };
   if (type === 'insert') queryOptions.checkKeys = true;
   if (typeof options.checkKeys === 'boolean') queryOptions.checkKeys = options.checkKeys;