Function handler

test/route.3.test.js:33–37

(req, res)

      params: { an_id: joi.number() }
    },
    handler (req, res) {
      t.assert.strictEqual(Object.keys(req.params).length, 1)
      t.assert.strictEqual(req.params.an_id, '42')
      res.send({ hello: 'world' })
    }
  })

  fastify.inject({