NODE-475 ensure create/ensure/drop indexes use primary, ignoring any readpreferences

Author: christkv

lib/collection.js

@@ -1028,6 +1028,8 @@ Collection.prototype.dropIndex = function(indexName, options, callback) {
   var args = Array.prototype.slice.call(arguments, 1);
   callback = args.pop();
   options = args.length ? args.shift() || {} : {};
+  // Run only against primary
+  options.readPreference = ReadPreference.PRIMARY;
 
   // Delete index command
   var cmd = {'deleteIndexes':this.s.name, 'index':indexName};  
@@ -1139,6 +1141,7 @@ Collection.prototype.listIndexes = function(options) {
 Collection.prototype.ensureIndex = function(fieldOrSpec, options, callback) {
   if(typeof options == 'function') callback = options, options = {};
   options = options || {};
+  // Execute ensureIndex
   this.s.db.ensureIndex(this.s.name, fieldOrSpec, options, callback);
 }
 

lib/db.js

@@ -710,6 +710,10 @@ Db.prototype.createIndex = function(name, fieldOrSpec, options, callback) {
   options = args.length ? args.shift() || {} : {};
   options = typeof callback === 'function' ? options : callback;
   options = options == null ? {} : options;
+  // Clone options
+  options = shallowClone(options);
+  // Run only against primary
+  options.readPreference = ReadPreference.PRIMARY;
 
   // Get the write concern options
   var finalOptions = writeConcern({}, self, options);
@@ -768,6 +772,10 @@ Db.prototype.ensureIndex = function(name, fieldOrSpec, options, callback) {
   var self = this;
   if(typeof options == 'function') callback = options, options = {};
   options = options || {};
+  // Clone options
+  options = shallowClone(options);
+  // Run only against primary
+  options.readPreference = ReadPreference.PRIMARY;
 
   // Get the write concern options
   var finalOptions = writeConcern({}, self, options);