storage fns for tx confirmation subs

lib/storage.js

@@ -25,6 +25,7 @@ var collections = {
   TX_NOTES: 'tx_notes',
   SESSIONS: 'sessions',
   PUSH_NOTIFICATION_SUBS: 'push_notification_subs',
+  TX_CONFIRMATION_SUBS: 'tx_confirmation_subs',
 };
 
 var Storage = function(opts) {
@@ -78,6 +79,10 @@ Storage.prototype._createIndexes = function() {
   this.db.collection(collections.PUSH_NOTIFICATION_SUBS).createIndex({
     copayerId: 1,
   });
+  this.db.collection(collections.TX_CONFIRMATION_SUBS).createIndex({
+    copayerId: 1,
+    txid: 1,
+  });
 };
 
 Storage.prototype.connect = function(opts, cb) {
@@ -935,6 +940,42 @@ Storage.prototype.removePushNotificationSub = function(copayerId, token, cb) {
   }, cb);
 };
 
+Storage.prototype.fetchActiveTxConfirmationSubs = function(copayerId, cb) {
+  this.db.collection(collections.TX_CONFIRMATION_SUBS).find({
+    copayerId: copayerId,
+    isActive: true,
+  }).toArray(function(err, result) {
+    if (err) return cb(err);
+
+    if (!result) return cb();
+
+    var subs = _.map([].concat(result), function(r) {
+      return Model.TxConfirmationSub.fromObj(r);
+    });
+    return cb(null, subs);
+  });
+};
+
+Storage.prototype.storeTxConfirmationSub = function(txConfirmationSub, cb) {
+  this.db.collection(collections.TX_CONFIRMATION_SUBS).update({
+    copayerId: txConfirmationSub.copayerId,
+    txid: txConfirmationSub.txid,
+  }, txConfirmationSub, {
+    w: 1,
+    upsert: true,
+  }, cb);
+};
+
+Storage.prototype.removeTxConfirmationSub = function(copayerId, txid, cb) {
+  this.db.collection(collections.TX_CONFIRMATION_SUBS).remove({
+    copayerId: copayerId,
+    txid: txid,
+  }, {
+    w: 1
+  }, cb);
+};
+
+
 Storage.prototype._dump = function(cb, fn) {
   fn = fn || console.log;
   cb = cb || function() {};