code: function configure(config) {
      var key,
          layout = null,
          fields = {},
          options = {
              port: (typeof config.port === "number") ? config.port : 5959,
              host: (typeof config.host === "string") ? config.host : 'localhost',
              debug: config.debug || false
          };
  
      if (config.batch) {
          options.batch = true;
          options.batchSize = config.batch.size;
          options.batchTimeout = config.batch.timeout;
      }
  
      if (config.fields && typeof config.fields === 'object') {
          for (key in config.fields) {
              if (typeof config.fields[key] !== 'function') {
                  fields[key] = config.fields[key];
              }
          }
      }
      return logStashAppender(options, fields, layout);
  }
docs: Config method, calls logStashAppender to return the logging function
  
  @param config
  @returns {Function}