Author: John Au-Yeung

To fix Node.js only processing six requests at a time, we can increase the max number of sockets.

To do this, we write

http.globalAgent.maxSockets = 20;

to increase the max number of simultaneous requests to 20.

to check in Node if module exists and if exists to load, we add a try-catch block.

For instance, we write

try {
  const m = require("/home/test_node_project/per");
} catch (ex) {
  handleErr(ex);
}

to call require to require the /home/test_node_project/per module.

If the module can’t be included, then the catch block runs.

To check Node Mongoose connection state without creating a new connection, we get the connection property.

For instance, we write

require("./app.js");
const mongoose = require("mongoose");

console.log(mongoose.connection.readyState);

to get the mongoose.connect.readyState property to check if the Mongoose connection is ready.

To run multiple commands in package.json with JavaScript, we use && to separate the commands.

For instance, in package.json, we write

{
  "scripts": {
    "init-assets": "webpack",
    "init-server": "node server/server.js",
    "start": "npm run init-assets && npm run init-server"
  }
}

to add the start script that runs the npm run init-assets and npm run init-server commands.

init-assets and init-server are the scripts added before start.

To fix ER_NOT_SUPPORTED_AUTH_MODE error on MySQL server, we add the user.

For instance, we run

ALTER USER 'root'@'localhost' IDENTIFIED WITH mysql_native_password BY 'password'

to add the root user to the database so we can log in with the user in our apps.