Angular 4 with nodejs and Mysql connectivity - mysql

Question

I am new in angular and node js. I want to know how angular connect with node js with mysql server. Which simple return query result. Can anyone help me.

Answer 1

Angular is a fronend framework and nodejs can be used to implement a backend for a system. And you can use mysql as your DBMS.
You have to implement your backend and frontend separately. From backend you are exposing endpoints, routes, apis to the external applications.
And you can access those apis,routes from angular using HttpClient module. You can make Http requests using that.
Hope this helps

Answer 2

You may need to use some libraries to make a connection between angular frontend and backend with MySQL database.
You will need the express.js to handle the backend for the data request. Because you use the MySQL database, the database language would be different from any others such as MongoDB. The express provided database integration for the different databases.
You also need a body-parser as a middleware to parse the request body. This is a very important part of your project. The req is very complicated and this middleware can help to get the information which you need.
Here is a sample of how to use express connect mysql.
var express = require('express');
var query = require('./query')
var bodyParser = require('body-parser');
var cookieParser = require('cookie-parser');
var app = express();
//Middleware for bodyparsing using both json and urlencoding
app.use(bodyParser.urlencoded({ extended: false }))
app.use(bodyParser.json())
app.all('*', function(req, res, next) {
res.header("Access-Control-Allow-Origin", "*");
res.header('Access-Control-Allow-Methods', 'PUT, GET, POST, DELETE, OPTIONS');
res.header("Access-Control-Allow-Headers", "X-Requested-With");
res.header('Access-Control-Allow-Headers', 'Content-Type');
next();
});
//login
app.post('/login',(req,res)=>{
var opts = req.body;
query(" SELECT *FROM `v_users` WHERE userAcount = ?",opts.userName).then((result)=>{
var response = result[0];
if(opts.password !== response.u_password){
return res.send({
errorCode:'404',
errorMsg:'password error'
})
}
//loginToken
var loginToken = response.userAcount + Math.random()*Math.pow(10,16)
res.send({
loginToken:loginToken
})
})
})
var server = app.listen(3000,()=>{
console.log('success')
})
Here is the query method:
(function() {
var mysql = require('mysql');
// var session = require('cookie-session');
var query = (sql,key) => {
var connection = mysql.createConnection({
host: 'localhost',
user: 'root',
password: 'root123',
database: 'm_users'
});
connection.connect()
var promise = new Promise((resolve,reject)=>{
connection.query(sql,[key], function(error, results, fields) {
if(error){
reject(error)
}else{
resolve(results);
}
});
connection.end();
});
return promise;
}
module.exports = query;
})()