code: function getCache(key, doesDateMatter, callback) {
      key = key.replace(/\//g, '-');
      var cacheFile = __dirname + '/' + CACHE_PREFIX + key + '.cache';
      fs.exists(cacheFile, function (exists) {
          if (exists) {
              fs.stat(cacheFile, function (err, stats) {
                  if (err) {
                      throw err;
                  }
                  if (!doesDateMatter || (stats.mtime.valueOf() > (new Date().valueOf() - 60 * 60 * 1000))) {
                      // The cache is less than 60 minutes old so return the contents
                      fs.readFile(cacheFile, function (err, data) {
                          if (err) {
                              console.error('Error reading the cache file at ' + cacheFile);
                              throw err;
                          }
                          var dataString = data.toString();
                          var dataObj;
                          try {
                              dataObj = JSON.parse(dataString);
                          } catch(e) {
                              dataObj = null;
                          }
  
                          callback(dataObj, stats.mtime);
                          return;
                      });
                  } else {
                      // The cache is older than 60 minutes
                      callback(null);
                      return;
                  }
              });
          } else {
              // The cache doesn't exist
              callback(null);
              return;
          }
      });
  }
docs: /*
  Get the item from the cache if exists
  
  @param string key
  @param Function callback
  @invoke callback(mixed response)