fastify.log is undefined

[zairl23]

I just follow the doc: https://github.com/fastify/fastify/blob/master/docs/Getting-Started.md

start a server.js:

```
// Require the framework and instantiate it
const fastify = require('fastify')()

// Declare a route
fastify.get('/', function (request, reply) {
reply.send({ hello: 'world' })
})

// Run the server!
fastify.listen(3000, function (err) {
if (err) throw err
fastify.log.info(server listening on ${fastify.server.address().port})
})

but throw the error: **TypeError: Cannot read property 'info' of undefined**

Then add the option : {logger: true}

 ```
// Require the framework and instantiate it
const fastify = require('fastify')({logger: true})

// Declare a route
fastify.get('/', function (request, reply) {
  reply.send({ hello: 'world' })
})

// Run the server!
fastify.listen(3000, function (err) {
  if (err) throw err
  fastify.log.info(`server listening on ${fastify.server.address().port}`)
})

the error still happen, i read the other docs, find the server.js below is work!

// Require the framework and instantiate it
const log = require('pino')({ level: 'info' })
const fastify = require('fastify')({logger: true})

// Declare a route
fastify.get('/', function (request, reply) {
  request.log.info('here');
  reply.send({ hello: 'world' })
})

// Run the server!
fastify.listen(3000, function (err) {
  if (err) throw err
  log.info(`server listening on ${fastify.server.address().port}`)
})

Is there something else i missed or there is something wrong with the docs?

[jsumners]

The issue is that the documentation is tied to the latest on the master branch. The docs are referring to a breaking change merged by #436 that hasn't been published as a release yet. So you will need to reference fastify.logger for now.

cc: @delvedor @mcollina

[mcollina]

we need to do a release.

[zairl23]

3ks, i know @jsumners, @mcollina