get cartridge counts from db

lib/plugins.js

@@ -1,5 +1,7 @@
 'use strict';
 
+var fs = require('fs');
+
 var _ = require('lodash');
 var async   = require('async');
 var logger  = require('./logger');
@@ -35,6 +37,13 @@ var reapTxInterval = null;
 
 var tradesQueue = [];
 
+var cartridges = null;
+try {
+  cartridges = JSON.parse(fs.readFileSync('./cartridges.json'));
+} catch (ex) {
+  logger.warn('No cartridges.json file found: ' + ex.message);
+}
+
 // that's basically a constructor
 exports.init = function init(databaseHandle) {
   if (!databaseHandle) {
@@ -187,6 +196,36 @@ exports.logEvent = function event(session, rawEvent) {
   db.recordDeviceEvent(session, rawEvent);
 };
 
+function buildCartridges(counts) {
+  if (!cartridges) return null;
+  return {
+    cartridges: [
+      {
+        denomination: cartridges.cartridges[0],
+        count: counts[0]
+      },
+      {
+        denomination: cartridges.cartridges[1],
+        count: counts[1]
+      },
+    ],
+    virtualCartridges: cartridges.virtualCartridges
+  };
+}
+
+exports.pollQueries = function pollQueries(session, cb) {
+  async.parallel([
+    async.apply(db.dispenseStatus, session),
+    async.apply(db.cartridgeCounts, session)
+  ], function(err, results) {
+    if (err) return cb(err);
+    return cb(null, {
+      dispenseStatus: results[0],
+      cartridges: buildCartridges(results[1])
+    });
+  });
+};
+
 function _sendBitcoins(toAddress, satoshis, cb) {
   var transactionFee = cachedConfig.exchanges.settings.transactionFee;
   walletPlugin.sendBitcoins(toAddress, satoshis, transactionFee, cb);