server.js

var express = require("express");
var bodyParser = require("body-parser");
var app = express();
var api = express();
app.use("/api", api);
api.use(bodyParser.urlencoded({ extended: false }));
api.use(bodyParser.json());
const creds = require("./credential.json");
const MongoClient = require("mongodb").MongoClient;
const url =
  "mongodb://" +
  creds.user +
  ":" +
  creds.pass +
  "@ds0" +
  creds.port +
  ".mlab.com:" +
  creds.port +
  "/" +
  creds.db;
const path = require("path");
app.use(express.static(path.join(__dirname, "front-end/build")));
console.log(url);

function findRecetas(db, callback, ingredientes) {
  const c = db.collection("RecetasPaTodos");
  if (ingredientes.length) {
    c.find({ ingredientes: { $all: ingredientes } }).toArray((err, docs) => {
      if (err) throw err;

      callback(docs);
    });
  } else {
    c.find().toArray((err, docs) => {
      if (err) throw err;

      callback(docs);
    });
  }
}

function getRecetas(callback, ingredientes) {
  MongoClient.connect(url, (err, client) => {
    if (err) throw err;
    console.log("Connected successfully to server");
    const db = client.db("webdev");

    findRecetas(db, callback, ingredientes);
    client.close();
  });
}

function postReceta(db, callback, receta) {
  const col = db.collection("RecetasPaTodos");
  col.save(receta, (err, r) => {
    if (err) throw err;
    console.log(r);
    callback(receta);
  });
}

function postRe(callback, receta) {
  MongoClient.connect(url, (err, client) => {
    if (err) throw err;
    console.log("Connected successfully to server");
    const db = client.db("webdev");

    postReceta(db, callback, receta);
    client.close();
  });
}

app.get("*", (req, res) => {
  res.sendFile(path.join(__dirname + "/front-end/build/index.html"));
});

api.post("/getData", function(req, res) {
  console.log("getData");
  getRecetas(function(tweets) {
    res.send(tweets);
  }, req.body.ingredientes);
});

api.post("/postReceta", (req, res) => {
  console.log("entro");
  postRe(r => res.send(r), req.body);
});

api.get("/", function(req, res) {
  console.log("api general");
  getRecetas(function(tweets) {
    res.send(tweets);
  }, []);
});

app.listen(3001, () => {
  console.log("Listening on:3001");
});