add indexes for commong db opperations

lib/storage.js

@@ -25,12 +25,39 @@ var Storage = function(opts) {
   this.db = opts.db;
 };
 
+Storage.prototype._createIndexes = function() {
+  this.db.collection(collections.WALLETS).createIndex({
+    id: 1
+  });
+  this.db.collection(collections.COPAYERS_LOOKUP).createIndex({
+    copayerId: 1
+  });
+  this.db.collection(collections.TXS).createIndex({
+    walletId: 1,
+    id: 1,
+  });
+  this.db.collection(collections.TXS).createIndex({
+    walletId: 1,
+    isPending: 1,
+  });
+  this.db.collection(collections.NOTIFICATIONS).createIndex({
+    walletId: 1,
+    id: 1,
+  });
+  this.db.collection(collections.ADDRESSES).createIndex({
+    walletId: 1
+  });
+  this.db.collection(collections.ADDRESSES).createIndex({
+    address: 1,
+  });
+};
+
 Storage.prototype.connect = function(opts, cb) {
   var self = this;
 
   opts = opts || {};
 
-  if (this.db) return cb(null);
+  if (this.db) return cb();
 
   var config = opts.mongoDb || {};
   mongodb.MongoClient.connect(config.uri, function(err, db) {
@@ -39,8 +66,9 @@ Storage.prototype.connect = function(opts, cb) {
       return cb(err);
     }
     self.db = db;
+    self._createIndexes();
     console.log('Connection established to ', config.uri);
-    return cb(null);
+    return cb();
   });
 };