definma-api/src/index.ts

import express from 'express';
import bodyParser from 'body-parser';
import swagger from 'swagger-ui-express';
import jsonRefParser, {JSONSchema} from '@apidevtools/json-schema-ref-parser';
import contentFilter from 'content-filter';
import mongoSanitize from 'mongo-sanitize';
import db from './db';


// tell if server is running in debug or production environment
console.log(process.env.NODE_ENV === 'production' ? '===== PRODUCTION =====' : process.env.NODE_ENV === 'test' ? '' :'===== DEVELOPMENT =====');


// mongodb connection
db.connect();

// create Express app
const app = express();
app.disable('x-powered-by');

// get port from environment, defaults to 3000
const port = process.env.PORT || 3000;

//middleware
app.use(express.json({ limit: '5mb'}));
app.use(express.urlencoded({ extended: false, limit: '5mb' }));
app.use(bodyParser.json());
app.use(contentFilter());  // filter URL query attacks
app.use((req, res, next) => {  // filter body query attacks
  req.body = mongoSanitize(req.body);
  next();
});
app.use((err, req, res, ignore) => {  // bodyParser error handling
  res.status(400).send({status: 'Invalid JSON body'});
});
app.use((req, res, next) => {  // no database connection error
  if (db.getState().db) {
    next();
  }
  else {
    res.status(500).send({status: 'Internal server error'});
  }
});
app.use(require('./helpers/authorize'));  // handle authentication

// require routes
app.use('/', require('./routes/root'));
app.use('/', require('./routes/user'));

// Swagger UI
let oasDoc: JSONSchema = {};
jsonRefParser.bundle('oas/oas.yaml', (err, doc) => {
  if(err) throw err;
  oasDoc = doc;
  oasDoc.paths = oasDoc.paths.allOf.reduce((s, e) => Object.assign(s, e));
  swagger.setup(oasDoc, {defaultModelsExpandDepth: -1, customCss: '.swagger-ui .topbar { display: none }'});
});
app.use('/api', swagger.serve, swagger.setup(oasDoc, {defaultModelsExpandDepth: -1, customCss: '.swagger-ui .topbar { display: none }'}));

app.use((req, res) => {  // 404 error handling
  res.status(404).json({status: 'Not found'});
});

app.use((err, req, res, ignore) => {  // internal server error handling
  console.error(err);
  res.status(500).json({status: 'Internal server error'});
});


// hook up server to port
const server = app.listen(port, () => {
  console.log(process.env.NODE_ENV === 'test' ? '' : `Listening on http://localhost:${port}`);
});

module.exports = server;