auth.index.js

const auth = require('feathers-authentication');
const FacebookTokenStrategy = require('passport-facebook-token');
// const GooglePlusTokenStrategy = require('passport-google-plus-token');
const local = require('feathers-authentication-local');
const jwt = require('feathers-authentication-jwt');
const oauth2 = require('feathers-authentication-oauth2');

module.exports = function () {
  const app = this;

  const config = app.get('auth');

  app.configure(auth(config))
    .configure(local())
    .configure(jwt())
    .configure(oauth2({
      name: 'facebook',
      Strategy: FacebookTokenStrategy,
    }));
    /* .configure(oauth2({
      name: 'google',
      Strategy: GooglePlusTokenStrategy,
    }));*/

  app.service('authentication').hooks({
    before: {
      create: [
        auth.hooks.authenticate(['local', 'facebook', 'google']),
      ],
      remove: [
        auth.hooks.authenticate('jwt'),
      ],
    },
  });
};

config.json

{
  "host": "localhost",
  "port": 3030,
  "mongodb": "mongodb://localhost:27017/db",
  "public": "../public/",
  "auth": {
    "secret": "Your secret",
    "facebook": {
      "clientID": "XXXXX",
      "clientSecret": "ZZZZZ"
    },
    "google": {
      "clientID": "",
      "clientSecret": ""
    }
  }
}

Send the token

POST /authentication

body: {
  "access_token": "kjbILH7hl8hpbyPBUP9...",
  "strategy": "facebook"
}

RESPONSE:
{
  "access_token": "....."
}