Cannot read .sign of undefined error being thrown with Fastify

Question

I am creating my server the following way:

const createServer = options => {
  const { logSeverity } = options;

  const server = Fastify({
    ignoreTrailingSlash: true
  });


  server.listen(5000, err => {
    if (err) {
      server.log.error(err);
      console.log(err);
      process.exit(1);
    }
  });

  server.register(AutoLoad, {
    dir: path.join(__dirname, "api", "routes")
  });

  server.register(jwt, {
    secret: nconf.get("secrets.jwt")
  });
};

And in one of my modules at ./some/child/path/signToken.js, I do:

const nconf = require("nconf");
const jwt = require("fastify-jwt");

const signToken = payload => {
  fastify.jwt.sign(payload, nconf.get("secrets.jwt"), (err, token) => {
    if (err) throw err;

    const response = {
      userId: payload.user._id,
      username: payload.user.username,
      token
    };

    return response;
  });
};

module.exports = { signToken };

Which throws an error, Cannot read property 'sign' of undefined.

According to the docs,

This will decorate your fastify instance with the standard jsonwebtoken methods

What am I doing wrong here? Is this perhaps not possible because I am creating a server, and server is my fastify instance? Would I then have to import server somehow?

asking this is silly but have you imorted **const fastify = require('fastify')** — Shubham Tiwari, Oct 24 '19 at 11:21
I have before, got rid of it because it still throws undefined either way, not silly at all — Mike K, Oct 24 '19 at 11:45
i think this is a good examle here in npm [ https://www.npmjs.com/package/fastify-jwt ] .might be there is problem in utilization of module — Shubham Tiwari, Oct 24 '19 at 11:49
how do you load `signToken.js`? Right now the `fastify.jwt.sign` variable does not exist — Manuel Spigolon, Oct 24 '19 at 12:37

score 1 · Answer 1 · answered Jun 23 '20 at 18:06

You are starting your server with

server.listen(5000...

Before registering your plugins.

According to the fastify docs the proper order is:

plugins (from the fastify ecosystem)
your plugins (your custom plugins)
decorators
hooks and middlewares
your services

This should happen before calling fastify.listen().

Cannot read .sign of undefined error being thrown with Fastify

1 Answers1