title: How to get query string in koa with koa-bodyparser?
body: <p>app.js</p>
  
  <pre><code>var bodyParser = require('koa-bodyparser');
  
  app.use(bodyParser());
  app.use(route.get('/objects/', objects.all));
  </code></pre>
  
  <p>objects.js</p>
  
  <pre><code>module.exports.all = function * all(next) {
    this.body = yield objects.find({});
  };
  </code></pre>
  
  <p>This works fine for get all objects. But I wanna get by query param, something like this localhost:3000/objects?city=Toronto How to use "city=Toronto" in my objects.js?</p>