Express not fetching data from postgres database. No errors displayed - node.js

I found someone with the exact same problem as me, but it had no answers. So I am copy-pasting this guy's question, hope someone can help me:
This is a difficult question for me to ask because I'm not truly sure what the issue is.
I have an Express JS server for routing and Node Postgres (PG) for the pool.
When I either go directly to localhost or use POSTMAN to test the routes there is no response except a simple loading screen. With POSTMAN, it gets stuck like so:
POSTMAN sending request...
Or for localhost it simply stays buffering/loading.
I am following this video on how to deploy a PERN app to Heroku. However, even after cloning the repo and updating all the packages within I cannot fetch data from my database (I am using PostgreSQL). I have updated all the database login information so it's not that.
Below is my code:
Server:
const express = require("express");
const app = express();
const cors = require("cors");
const pool = require("./db");
app.use(cors());
app.use(express.json());
app.get("/todos", async (req, res) => {
try {
console.log("route hit"); // this msg gets displayed when i send a req
const allTodos = await pool.query("SELECT * FROM todo");
console.log("route hit again"); // this msg does not gets displayed when i send a req
res.json(todo.rows[0]);
} catch (err) {
console.error(err.message);
}
});
app.listen(5000, () => {
console.log("server has started on port 5000");
});
Pool
const Pool = require("pg").Pool;
const pool = new Pool({
user: "postgres",
password: "postgres",
host: "localhost",
port: 5432,
database: "perntodo"
});
module.exports = pool;
All pool information is correct.
I have checked my database and there are active tables and data.
Again, there are no errors displayed so it's super hard for me to diagnose the problem.

Try exporting pool like in the docs:
module.exports = {
query: (text, params) => pool.query(text, params),
}

Related

Make post request to Mongodb Atlas using Nodejs

I was familiar with MongodB for CRUD operation. Here, I'm trying to make simple post request on mongodB atlas but I want to know where I have done error for the connection and posting data to MongodB atlas.
Model.js
const mongoose = require("mongoose");
const Schema = mongoose.Schema;
let quizSchema = new Schema({
title: {
type: String,
},
description: {
type: Number,
},
question: {
type: String,
},
});
const Quiz = mongoose.model("Quiz", quizSchema);
module.exports = Quiz;
index.js
I'm trying to create the database collection name "QuizDatabase" and insert the data to it.
var express = require("express");
var bodyParser = require("body-parser");
const Quiz = require("./views/model/model");
var Request = require("request");
var app = express();
app.use(bodyParser.json());
const MongoClient = require("mongodb").MongoClient;
const uri =
"mongodb+srv://username:password#cluster0.iom1t.mongodb.net/QuizDatabase?retryWrites=true&w=majority";
const client = new MongoClient(uri, {
useNewUrlParser: true,
useUnifiedTopology: true,
});
mongoose.connect(uri);
var server = app.listen(process.env.PORT || 8080, function () {
var port = server.address().port;
console.log("App now running on port", port);
});
app.post("/new/", function (req, res) {
Quiz.collection("QuizDatabase").insertMany(req.body, function (err, doc) {
if (err) {
handleError(res, err.message, "Failed to create new quiz.");
} else {
res.status(201).send(JSON.stringify(body));
}
});
});
function handleError(res, reason, message, code) {
console.log("ERROR: " + reason);
res.status(code || 500).json({ error: message });
}
You dont have to use mongo client if you are already using mongoose.
In index.js file just import the model
const Quiz = require("./model");
And you are already using mongoose to connect to db when you write mongoose.connect(uri); You don't have to use client.connect() again.
Query to insert -
Quiz.insertMany(req.body);
Your index file should look like this -
const Quiz = require("./views/model/model");
var Request = require("request");
var app = express();
app.use(bodyParser.json());
const uri =
"mongodb+srv://username:password#cluster0.iom1t.mongodb.net/QuizDatabase?retryWrites=true&w=majority";
mongoose.connect(uri);
var server = app.listen(process.env.PORT || 8080, function () {
var port = server.address().port;
console.log("App now running on port", port);
});
app.post("/new/", function (req, res) {
Quiz.insertMany(req.body, function (err, doc) {
if (err) {
handleError(res, err.message, "Failed to create new quiz.");
} else {
res.status(201).send(JSON.stringify(body));
}
});
});
function handleError(res, reason, message, code) {
console.log("ERROR: " + reason);
res.status(code || 500).json({ error: message });
}
There are several reasons.
Connection Issues to the MongoDB database.
To check this insert app.listen() into mongoose connect. This would make sure you can only run development on your preferred PORT only when it has successfully connected to your Database. e.g From your code
mongoose.connect(uri)
.then(() => {
//listen for PORT request
var server = app.listen(process.env.PORT || 8080, function () {
var port = server.address().port;
console.log("App now running on port", port);
});
}).catch((error) => {
console.log(error);
});
Try purposely using the wrong Username or Password and see if you get this error:
MongoServerError: bad auth : Authentication failed.
at Connection.onMessage (/Users/user/Documents/..<pathway>../connection.js:207:30)
*
*
*
*
ok: 0,
code: 8000,
codeName: 'AtlasError',
[Symbol(errorLabels)]: Set(1) { 'HandshakeError' } }
If you don't get this error then you have a connection problem. To solve this, I added my current IP ADDRESS and 0.0.0.0/0 (includes your current IP address) at the Network Access page. So you click on MY CURRENT IP ADDRESS and confirm upon setting up the network. Go to NETWORK ACCESS, click on add new IP ADDRESS, input 0.0.0.0/0 and confirm. Then try using the wrong username or password in the URI link given to you to see if it gives the above-expected error, then you can now correct the Username and Password, and npm run dev or npm start (However you configured it in your package.json file).
Code issues
First of I would correct your Model.js file from this:
const Quiz = mongoose.model("Quiz", quizSchema);
module.exports = Quiz;
to this:
module.exports = mongoose.model("Quiz", quizSchema);
I can see why yours can work, but it may be an issue as you want to get the schema upon accessing the whole file.
Secondly, I would correct the code for Posting and you can do that in 2 ways using the asynchronous method. Which depends on the method of assigning the req.body.
Way 1:
app.post("/new/", async (req, res) => {
const { title, description, question } = req.body;
//adds doc to db
try {
const quiz = await Quiz.create({ title, description, question });
res.status(200).json(quiz);
} catch (error) {
res.status(400).json({ error: error.message });
}
});
OR
Way2:
app.post("/new/", async (req, res) => {
const quiz = new Quiz(req.body);
//adds doc to db
try {
const savePost = await quiz.save();
response.status(200).send(savePost);
} catch (error) {
response.status(400).send(error);
}
});
NOTE: You don't necessarily have to create a named database and collection in Mongo Atlas before starting the project. The URI given to you covers that if there are no problems with the connection to the DB or the Code.
based on your code
URI:
"mongodb+srv://username:password#cluster0.iom1t.mongodb.net/QuizDatabase?retryWrites=true&w=majority";
would create a database called: QuizDatabase and collection called: quizs (MongoDb always creates the plural word from the model given and makes it start with lowercase (i.e from your Model.js, the mongoose.model("Quiz"))).
If no database is named in your URI, then a database called test is automatically created for you as a default database, with the collection name being the mongoose.model("") given.
CONCLUSION
This should solve at least 90% of your issues, any other creation/POST problems is currently beyond my current expertise. Happy Coding 🚀🚀🚀

Node: VM12:1 POST http://localhost:3000/auth net::ERR_CONNECTION_REFUSED

I am new to fullstack development and I want to deploy a project that will be used on the same network by different users. I have used angular for the front-end and node/express and MySQL for the backend. Before proper deployment, for testing purposes, I am accessing my application from another computer that is on the same network. The application, however, is throwing an error when I try to login.
VM12:1 POST http://localhost:3000/auth net::ERR_CONNECTION_REFUSED
Here's my backend code:
server.js
const express = require('express');
const bodyParser = require('body-parser');
const cors = require('cors');
const mysqlConnection = require('./connection');
const routes = require('./routes');
const http = require('http');
const path = require('path');
var app = express();
app.disable('x-powered-by');
app.use(express.static(__dirname + '/dist'));
app.get('/*', (req, res) => res.sendFile(path.join(__dirname)));
app.use(cors());
app.use(bodyParser.json());
app.use(routes);
const port = process.env.PORT || 3000;
const server = http.createServer(app);
server.listen(port, '0.0.0.0', () => console.log(`Running on port ${port}`));
routes.js
router.post("/auth", (req, res) => {
var email = req.body.email;
var password = req.body.password;
var accessBasic = "Basic";
var accessPremium = "Premium";
mysqlConnection.query("SELECT * FROM authorization WHERE email = ? AND password = ?", [email,
password], (err, results) => {
if(!err)
{
var myJSON = JSON.stringify(results);
var check_email = myJSON.search(/email/i);
var check_password = myJSON.search(password);
var check_access = myJSON.search(accessBasic);
var check_access2 = myJSON.search(accessPremium);
if ((check_email != -1) && (check_password != -1) && (check_access != -1))
{
res.send("Successfully Authorized to Basic Access");
}
else if ((check_email != -1) && (check_password != -1) && (check_access2 != -1))
{
res.send("Successfully Authorized to Premium Access");
}
else
{
res.send("Authorization failed");
}
}
else
{
console.log("Connection to authorization failed: " + err.message);
}
})
})
I have allowed incoming connections in my firewall and done everything but, couldn't find the reason why my endpoint is refusing to connect while trying to connect on device other than my system on the same network. I don't know what's wrong. Anybody has any idea what am I doing wrong? I have hosted my application on my system and accessing it from another on the same network.
EDIT: Since, this question has gained quite a lot of views, I would like to mention that I didn't change any of the firewall settings as mentioned above. All the default firewall settings of the Windows OS were used. I just deployed the app and ran it.
ANSWER: I was having an issue on the front-end. I was targeting localhost instead of the IP address of the system that the app was hosted on. See my answer below for the details.
For anyone who is going to see this in future. I was having an error on my front-end. Instead of calling http://localhost:3000/name-of-my-api-endpoint, I changed the localhost to the IP address of my system and then ran ng build --prod again in order to make new static files and serve them from node.js.
I have experienced the same issue with MongoDB
I have found out that the problem was my MongoDB wasn't connected to my localhost and the issue was related to tokens and authentication.
So I went to my terminal on my backend folder and ran the command -
npm install dotenv --save
Then I created my .env file located in my backend folder
and added the following commands
PORT=3000 APP_SECRET="RANDOM_TOKEN_SECRET"
MONGODB="mongodb+srv://youruser:yourpassword#cluster0.k06bdwd.mongodb.net/?retryWrites=true&w=majority"
Then called it in my app.js file
const dotenv = require("dotenv");
dotenv.config();
mongoose.connect(process.env.MONGODB,
{ useNewUrlParser: true,
useUnifiedTopology: true })
.then(() => console.log('Connected to MongoDB!'))
.catch(() => console.log('Failed to connect to MongoDB !'));
module.exports = app;
Finally I have added it in my backend/controllers/user.js
const token = jwt.sign(
{userId: user._id},
process.env.APP_SECRET,
{expiresIn: '24h'});
res.status(200).json({
userId: user._id,
token: token
});
You can access your app in the same network from your #IP not from localhost (127.0.0.1) change it to 192.168.1.X (your local #IP address) and make sure to changed it in your .env file.

How can I connect my local node.js app to my Heroku Postgres database?

I've managed to get my Node.js app working properly with my Heroku Postgres database when the node application is deployed to Heroku. However having to deploy to heroku each time I make a code change is a bit arduous and I'd rather be able to develop locally and connect to the database from my local app.
https://devcenter.heroku.com/articles/connecting-to-heroku-postgres-databases-from-outside-of-heroku
The above article doesn't really describe how this is done, I'm not exactly sure what I need to do.
If I attempt to run my app locally and access an endpoint that queries my database I get
Error Error: connect ECONNREFUSED 127.0.0.1:5432
Whereas if I access the same endpoint from my heroku deployed app it works correctly.
Here's my app
const express = require('express')
const path = require('path')
const PORT = process.env.PORT || 5000;
const { Pool } = require('pg');
const pool = new Pool({
connectionString: process.env.DATABASE_URL,
ssl: {
rejectUnauthorized: false
}
});
express()
.use(express.static(path.join(__dirname, 'public')))
.set('views', path.join(__dirname, 'views'))
.set('view engine', 'ejs')
.get('/', (req, res) => res.render('pages/index'))
.get('/users', async (req, res) => {
try {
const client = await pool.connect();
const result = await client.query('SELECT * FROM users');
const results = { 'results': (result) ? result.rows : null};
console.log(results);
res.status(200).json(results);
} catch (err) {
console.error(err);
res.send("Error " + err);
}
})
.listen(PORT, () => console.log(`Listening on ${ PORT }`));
I think you need to update the the process.env.DATABASE_URL on your local machine. From the error, it looks like the DATABASE_URL refers to localhost while you want to use the db hosted on Heroku.
I understand that you only want to use the remote db only. The error says you're unable to connect to 127.0.0.1:5432. This is the IP address of localhost, not the remote database. Your code is trying to connect to 127.0.0.1:5432 for some reason while it should be trying to connect to the remote db.
Did you use the dotenv to access process.env.DATABASE_URL ?
You need dotenv.config(); worked for me.

NodeJS killed when react-native app is closed

Actually i'm new to react and node and i was trying to make a simple NodeJS server which return some data from MySQL Database but i'm having some issues with the back-end part.
Actually i've installed NodeJS in another computer and followed this guide to deploy it.
Then in my React-Native app i just do simple fetch call to the NodeJS with the ip of the computer where the back-end part is installed till here all work fine and even from my personal computer i can get the data from NodeJS server but i face the issue when after loading data in React-App i kill that app and then i reopen it after that seems the server just die and i have to restart it with command 'node myfile.js'
After killing the app, NodeJS server is impossible to reach from any device and in browser after some minutes of load just return 'PAGE DOESN'T WORK ERR_EMPTY_RESPONSE'
Here is routes.js file located in another PC
const express = require('express');
const bodyParser = require('body-parser');
const mysql = require('mysql');
const connection = mysql.createPool({
host : 'localhost',
user : 'root',
password : 'block',
database : 'mydb'
});
// Starting our app.
const app = express();
// Creating a GET route that returns data from the 'users' table.
app.get('/prenotazioni', function (req, res) {
// Connecting to the database.
connection.getConnection(function (err, connection) {
// Executing the MySQL query (select all data from the 'users' table).
connection.query("SELECT Data, Importo_Doc FROM tabella_pagamenti", function (error, results, fields) {
// If some error occurs, we throw an error.
if (error) throw error;
// Getting the 'response' from the database and sending it to our route. This is were the data is.
res.send(results)
});
});
});
// Starting our server.
app.listen(3000, () => {
console.log('Vai su http://localhost:3000/prenotazioni per vedere i dati.');
});
While method in my react-app where i call fetch is the following
GetData = () => {
return fetch('http://192.168.100.160:3000/prenotazioni')
.then((response) => response.json())
.then((responseJson) => {
this.setState({
isLoading: false,
dataSource: responseJson,
}, function(){
});
})
.catch((error) =>{
console.error(error);
});
}

How get response from express server for ajax query in nuxtjs

I'm want to get data from the node/express server after send ajax query from any page of the nuxtjs app.
Usually, for getting and sending ajax query in PHP server, I'm do like this $_GET['var']; echo json_encode('Server got data');
Now I want to use node server express for saving data in mongodb.
When I trying to send a query, response return full code of file test.js.
File index.vue
methods: {
onServer() {
this.$axios.get('/server/test').then(res => {
console.log('res', res.data)
})
}
}
File test.js
var express = require('express');
var app = express();
app.get('*', function (req, res) {
res.send('Hello World!');
});
app.listen(3000, function () {
console.log('Example app listening on port 3000!');
});
File server/index.js
const express = require('express')
const consola = require('consola')
const { Nuxt, Builder } = require('nuxt')
const app = express()
// Import and Set Nuxt.js options
const config = require('../nuxt.config.js')
config.dev = !(process.env.NODE_ENV === 'production')
async function start() {
// Init Nuxt.js
const nuxt = new Nuxt(config)
const { host, port } = nuxt.options.server
// Build only in dev mode
if (config.dev) {
const builder = new Builder(nuxt)
await builder.build()
} else {
await nuxt.ready()
}
// Give nuxt middleware to express
app.use(nuxt.render)
// Listen the server
app.listen(port, host)
consola.ready({
message: `Server listening on http://${host}:${port}`,
badge: true
})
}
start()
I'm a new user node, please help me!
Your main issue is that you are targeting "test.js" in your axios url. This is why it responds with the file rather than what the get route should respond with.
So try with:
this.$axios.get('http://nuxt-profi/server/test').then(...
and see what you get. You should also be able to access that in the browser, just go to your url http://nuxt-profi/server/test and it should show your "Hello World" reponse.
However I can't be sure how you have set all this up. Are you running this as development? In which case maybe you should access it as http://localhost:3000/server/test but maybe you have virtual hosts configured like this. Also, is this a separate backend api or are you trying this as server middleware?
If this doesn't help please give us more info about your project setup and we'll go from there.

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