Query Parameters

ctx.query gives you access to the request's URL query string. It's both callable and indexable. Pick whichever reads better at the call site.

Reading Query Params

app.get('/search', async (ctx) => {
  const page = ctx.query('page'); // callable style
  const limit = ctx.query.limit; // property style
 
  return json({ page, limit });
});

A request to /search?page=2&limit=20 produces page: "2", limit: "20". All values are plain strings. Parse numbers/booleans yourself if needed.

Iterating All Params

Since query values are also set as own properties on the query function, Object.keys() gives you every param name:

app.get('/debug', async (ctx) => {
  const keys = Object.keys(ctx.query);
  return json({ keys });
});

Lazy Parsing

ctx.query is parsed from the request URL on first access and cached for the rest of the request. If a handler never reads ctx.query, the query string is never parsed at all, a small but deliberate performance detail.

Missing Params

Accessing a param that wasn't provided returns undefined. There's no throwing:

app.get('/items', async (ctx) => {
  const sort = ctx.query.sort ?? 'created_at'; // fall back to a default
  return json({ sort });
});