Develop Reference

Switching from mqtts protocol to wss in nodeJS

I can connect to my MQTT broker, using mqtts protocol like this:
mqtt = require('mqtt')
let options = {
host: '0d9d5087c5b3492ea3d302aae8e5fd90.s2.eu.hivemq.cloud',
port: 8883,
path: '/mqtt',
clientId: 'mqttx_2d803d2743',
protocol: 'mqtts',
username: 'light29',
password: 'Mqtt29#!',
cleanSession: true,
}
// initialize the MQTT client
let client = mqtt.connect(options);
// setup the callbacks
client.on('connect', function () {
console.log('Connected');
});
client.on('error', function (error) {
console.log(error);
});
client.on('message', function (topic, message) {
// called each time a message is received
console.log('Received message:', topic, message.toString());
});
// subscribe to topic 'my/test/topic'
client.subscribe('mytest');
// publish message 'Hello' to topic 'my/test/topic'
client.publish('mytest', 'Hello');
This code, yields, as expected:
Connected
Received message: mytest Hello
Now, I would like to connect to this same broker but using wss protocol instead, thus I tried:
let options = {
host: '0d9d5087c5b3492ea3d302aae8e5fd90.s2.eu.hivemq.cloud',
port: 8884,
path: '/mqtt',
clientId: 'mqttx_2d803d2743',
protocol: 'wss',
username: 'light29',
password: 'Mqtt29#!',
cleanSession: true,
}
However, in this case, I got:
Error: connect ECONNREFUSED 127.0.0.1:8884
at TCPConnectWrap.afterConnect [as oncomplete] (node:net:1161:16) {
errno: -61,
code: 'ECONNREFUSED',
syscall: 'connect',
address: '127.0.0.1',
port: 8884
}

I have finally managed to connect with these changes:
let options = {
username: 'light29',
password: 'Mqtt29#!',
}
// initialize the MQTT client
let client = mqtt.connect('wss://0d9d5087c5b3492ea3d302aae8e5fd90.s2.eu.hivemq.cloud:8884/mqtt', options);
Still, I do not know why explicitly passing protocol, host, port and path does solve it.

The problem in the original is that protocol in the options should be schema and should container URL schema e.g.
let options = {
host: '0d9d5087c5b3492ea3d302aae8e5fd90.s2.eu.hivemq.cloud',
port: 8883,
path: '/mqtt',
clientId: 'mqttx_2d803d2743',
schema: 'mqtts://',
username: 'light29',
password: 'Mqtt29#!',
cleanSession: true,
}
or
let options = {
host: '0d9d5087c5b3492ea3d302aae8e5fd90.s2.eu.hivemq.cloud',
port: 8883,
path: '/mqtt',
clientId: 'mqttx_2d803d2743',
schema: 'wss://',
username: 'light29',
password: 'Mqtt29#!',
cleanSession: true,
}
protocol is not a valid option.

Heroku with Strapi, Application is not using production database

I've deployed my app to Heroku. It gives an Application Error message upon visit.
The logs gave me this:
[2021-02-15T01:04:05.882Z] debug ⛔️ Server wasn't able to start properly.
[2021-02-15T01:04:05.883Z] error Error: connect ECONNREFUSED 127.0.0.1:5432
at TCPConnectWrap.afterConnect [as oncomplete] (net.js:1146:16)
Which according to my guess, is that its trying to use local database. I think the app is not using the database.js located in config/env/production. The application runs fine with heroku local.
Below is the database.js I set for production env:
const parse = require("pg-connection-string").parse;
const config = parse(process.env.DATABASE_URL);
module.exports = ({ env }) => ({
defaultConnection: "default",
connections: {
default: {
connector: "bookshelf",
settings: {
client: "postgres",
host: config.host,
port: config.port,
database: config.database,
username: config.user,
password: config.password,
ssl: {
rejectUnauthorized: false,
},
},
options: {
ssl: true,
},
},
},
});
Creating and printing the config var on heroku console results in expected values.

For some reason the deployment method in the strapi docs to heroku does not seem to work when you initially have set up your local database as Postgres.
I had the same problem as you and I fixed it using the NODE_ENV env variable.
Instead of creating a new production database config file in ./config/production/database.js you can simply extend the config file in ./config/database.js with the prod config and decide based on what NODE_ENV is set which one to return.
As example:
module.exports = ({ env }) => {
const parse = require("pg-connection-string").parse;
const config = parse(env("DATABASE_URL", "127.0.0.1"));
const devConfig = {
client: "postgres",
connection: {
host: env("DATABASE_HOST", "127.0.0.1"),
port: env.int("DATABASE_PORT", 5432),
database: env("DATABASE_NAME", "db_name"),
user: env("DATABASE_USERNAME", "root"),
password: env("LOCAL_DB_PASSWORD"),
ssl: env.bool("DATABASE_SSL", false),
},
};
const prodConfig = {
client: "postgres",
connection: {
host: config.host,
port: config.port,
database: config.database,
user: config.user,
password: config.password,
ssl: {
rejectUnauthorized: false,
},
},
debug: false,
};
return
env("NODE_ENV", "development") === "production" ? prodConfig : devConfig
};

Node.js - TypeError: Client is not a constructor

I am trying the following:
const { Client } = require('pg');
console.log(Client);
const client = new Client({
user: 'Username censored',
host: 'Host censored',
database: 'gisuebung',
password: 'Passworded censored',
port: 5432,
});
client.connect();
When I run this however, I get the following Error: Error in v-on handler: "TypeError: Client is not a constructor"
I wrote this after a snippet I found online and it seems everywhere I look people did the exact same thing. Can anyone tell me what I am doing wrong?

This is a JS error:
Try this, it worked for me:
const { Client } = require('pg');
const Client = require('pg').Client;
-- ES module:
import pg from 'pg';
const Client = pg.Client;

Your code fine for CommonJS.
But for ESM this error will raise.
Correct way to run in ESM:
import pg from 'pg'
const client = new pg.Client(config.dbConfig)

Try this, it worked for me:
const { Client } = require('pg');
const client = new Client({
user: "postgres",
database: "databasename",
port: 5432,
host: "localhost",
password: "yourpassword",
ssl: false
});
client.connect();
client.query("select * from cad_client")
.then(results => {
const result = results.rows
console.log(result)
})
.finally(() => client.end())

Why does couchDB gives me not authorized error when trying to create views

I am using couchDB and when ever i try to create views it is giving me this error
at processTicksAndRejections (internal/process/task_queues.js:97:5) {
code: 'EUNAUTHORIZED',
body: {
error: 'unauthorized',
reason: 'You are not a db or server admin.'
}
}
I am using Node-Couchdb and i am passing the credentials like this
const NodeCouchDb = require('node-couchdb')
require("dotenv-flow").config();
const couch = new NodeCouchDb({
host: process.env.DB_HOST,
protocol: process.env.DB_PROTOCOL,
port: process.env.DB_PORT
})
const couchAuth = new NodeCouchDb({
auth: {
user: process.env.DB_USER_NAME,
pass: process.env.PASSWORD
}
})
module.exports = {
couch
}

Your code is creating two instances of NodeCouchDB, couch and couchAuth where
couch points to server specified by envars without credentials
couchAuth points to the default server (127.0.0.1:5984) with credentials specified by envars
You need to combine parameters, for example
const NodeCouchDb = require("node-couchdb");
const couch = new NodeCouchDb({
host: process.env.DB_HOST,
protocol: process.env.DB_PROTOCOL,
port: process.env.DB_PORT,
auth: {
user: process.env.DB_USER_NAME,
pass: process.env.PASSWORD,
},
});
module.exports = {
couch
};

Connection between node and mysql crash

I have a connection between Node and MySQL with a external database:
const connectionDB = mysql.createConnection({
host: '178.129.145.252',
port: 3306,
user: '',
password: '',
database: '*****'
})
when I execute my script to start it runs and I can view the users in a table, but later it crashes
enter image description here anyone knows how can I connect with the external database?
Thanks

Your code does not properly handle connection loss to MySQL server.
A quick solution would be to use connection pool.
var db_config = {
host: 'localhost',
user: 'username',
password: 'password',
database: 'example'
};
let pool = mysql.createPool(dbConfig);
pool.on('connection', function (conn) {
if (conn) {
logger.info('Connected');
}
});
// DO SOMETHING HERE
// pool.query('QUERY GOES HERE', (err, rows) => { /* Handle query response */});