I can console.log the object that I want, but how can I retrieve the object outside of connection.query()?
var express = require('express');
var mysql = require("mysql");
var app = express();
var connection = mysql.createPool({
connectionLimit: 50,
host: "localhost",
user: "root",
password: "",
database: "sakila"
});
app.get('/', function(req, res){
connection.query('SELECT * FROM actor', function(err, rows) {
if(err) throw err;
var user = rows[0];
console.log(user);
});
res.send();
});
This is the result in the console:
node-databases> node .\database\db-1.js
RowDataPacket {
actor_id: 1,
first_name: 'PENELOPE',
last_name: 'GUINESS',
last_update: 2006-02-15T10:34:33.000Z }
I want to be able to take that and send it in the response to the browser.
Replace console.log with res.send thus sending response within the callback.
Related
I'm trying to query a single line from a 28k record database as a test but it isn't going through but when I load up 'localhost:3001/api/get' it stays loading, even though my connection says success? Is it actually even connecting to the db?
my data bases schema is:
id | state_name | city
const bodyParser = require('body-parser');
const express = require('express');
const app = express();
const mysql = require('mysql');
const cors = require('cors');
const db = mysql.createPool({
host: "localhost",
user: "root",
password: "password",
database: "states_city"
});
app.use(cors());
app.use(express.json());
app.use(bodyParser.urlencoded({extended:true}));
app.get('/api/get', (req, res)=>{
const sqlGet = "SELECT city FROM state_city city = 'Chicago'";
db.query(sqlGet, (err, res)=>{
console.log("success");
});
});
app.listen(3001, ()=>{
console.log("running on port 3001");
});
First you must make server running. Remove that API route you had set before running server.
app.listen(3001, ()=>{
console.log("running on port 3001");
});
Now you must create database connection. Create new file dbconn.js
var mysql = require('mysql');
const db = mysql.createPool({
host: "localhost",
user: "root",
password: "password",
database: "states_city"
});
Now create new connection:
var new_connection = mysql.createPool(
db
);
new_connection.on('connection', function (connection) {
console.log('DB Connection established');
connection.on('error', function (err) {
console.error(new Date(), 'MySQL error', err.code);
});
connection.on('close', function (err) {
console.error(new Date(), 'MySQL close', err);
});
});
// export connection
module.exports = new_connection;
Include that connection in other file:
var db_connection = require('../dbconn');
db_connection.query(query, params, function (error, results, fields) {
//Do your query
});
Read about project structure to make your code easy to edit.
I'm performing CRUD operations using MYSQL and NodeJS express. Their error in deleting a record from DB, I don't know why I was getting a problem as i have copied the delete query from SQL where it is working properly. Here it is 'DELETE FROM tblltest WHERE id=?'. I manually add 'id' like 'DELETE FROM tblltest WHERE id=2' then it will delete the record from DB. Please help me out to solve this issue. Here are my lines of code.
var express = require('express');
var mysql = require('mysql');
var app = express();
var connection = mysql.createConnection({
host: 'localhost',
user: 'root',
password: '',
database: 'sampledb'
});
app.delete('/:id' , function(req , resp) {
connection.query('DELETE FROM `tblltest` WHERE `id`=?' , function(error , rows , fields){
if(!error){
console.log('Successful deleted!! \n');
resp.json(rows);
}else{
console.log('Error in deleting');
}
});
})
app.listen(1337);
You need to access the id route parameter in your delete API Node method, and then also bind this id value to the delete query:
app.delete('/:id', function(req, resp) {
var id = req.params.id;
connection.query('DELETE FROM tblltest WHERE id = ?', [id],
function(error, rows, fields) {
if (!error) {
console.log('Successful deleted!! \n');
resp.json(rows);
}
else {
console.log('Error in deleting');
}
});
})
var express = require('express');
var app = express();
var mysql = require('mysql');
var bodyParser = require('body-parser');
//start mysql connection
var connection = mysql.createConnection({
host : 'localhost', //mysql database host name
user : 'root', //mysql database user name
password : '', //mysql database password
database : 'sampledb' //mysql database name
});
connection.connect(function(err) {
if (err) throw err
console.log('You are now connected...')
})
//end mysql connection
//start body-parser configuration
app.use( bodyParser.json() ); // to support JSON-encoded bodies
app.use(bodyParser.urlencoded({ // to support URL-encoded bodies
extended: true
}));
//end body-parser configuration
//create app server
var server = app.listen(1337, "127.0.0.1", function () {
var host = server.address().address
var port = server.address().port
console.log("Example app listening at http://%s:%s", host, port)
});
//rest api to delete record from mysql database
app.delete('/employees', function (req, res) {
console.log(req.body);
connection.query('DELETE FROM `tblltest` WHERE `id`=?', [req.body.id], function (error, results, fields) {
if (error) throw error;
res.end('Record has been deleted!');
});
});
I created a server.js file which looks like this.
var express = require('express'),
app = express(),
port = process.env.PORT || 3000;
app.listen(port);
console.log('todo list RESTful API server started on: ' + port)
var mysql = require('mysql');
var con = mysql.createConnection({
host: "localhost",
user: "**",
password: "**",
database: "test"
});
app.get('/nodeapi/getimg',function(req,res){
con.connect(function(err) {
if (err) throw err;
con.query("SELECT * FROM images", function (err, result, fields) {
if (err) throw err;
console.log(result[1].image);;
});
})})
When I run this file in my command terminal I get the correct result.
When I create a http.get function like this for my ionic app:
getimg(){
var url = 'http://localhost:3000/nodeapi/getimg';
this.http.get(url).subscribe(responseData => console.log(responseData));}
I get an error saying net::ERR_CONNECTION_REFUSED. I have looked everywhere but cannot seem to find it. I am using phpmyadmin for the database. Would anyone please be so kind to explain to me what I am doing wrong.
Give this example a try. Also, do you expect more than one result from your query? If not you will want to use result[0] not 1 to get the first (and maybe only) result (located at index 0).
var express = require('express');
var cors = require('cors');
var mysql = require('mysql');
var port = process.env.PORT || 3000;
var app = express();
app.use(cors());
app.options('*', cors());
var con = mysql.createConnection({
host: "localhost",
user: "**",
password: "**",
database: "test"
});
app.get('/nodeapi/getimg', function(req, res) {
con.connect(function(err) {
if(err) throw err;
con.query("SELECT * FROM images", function(err, result, fields) {
if(err) throw err;
console.log(result[1].image);
res.send(result[1].image); // send the value back to the caller.
});
})
})
app.listen(port, function() {
console.log('CORS-enabled web server listening on port 80')
})
I want to use url post params to execute mysql query. I am getting error during mysql command when I post through postman. I dont know what is problem with this code. Here is my code
var express = require('express');
var app = express();
var bodyParser = require('body-parser');
var mysql = require('mysql');
var md5 = require('MD5');
var con = mysql.createConnection({
host: "localhost",
user: "shoaib",
password: "",
database: "watch"
});
con.connect(function(err) {
if (err) throw err;
console.log("Connected!");
});
app.use(bodyParser.urlencoded({ extended: true }));
app.use(bodyParser.json());
var port = process.env.PORT || 8080;
var router = express.Router();
router.post('/',function(req, res) {
con.connect(function(err) {
var query = "Select * From user Where email=? AND password=?";
var table = [req.body.email,req.body.password ];
console.log(req.body);
query = mysql.format(query, table);
con.query(query, function (err, rows) {
if (err) {
res.json({ "Error": true, "Message": "Error executing MySQL query" });
} else if(rows!=0) {
res.json({ "Error": false, "Message": "Success","Users": rows });
} else {
res.json({ "Error": true,});
}
});
});
});
app.use('/api', router);
app.listen(port);
console.log('Magic happens on port ' + port);
Node is working perfectly but when I execute command url I face error.
Make sure on your request that you set the Content-Type header to application/json or application/x-www-form-urlencoded since your app supports either. Without a Content-Type header with either of these values body-parser will not read the request body and res.body will be undefined.
Example POST Request with Content-Type: application/json
const {request} = require('http')
const requestBody = {email: 'abc#gmail.com', password: 'abcdef123456'}
const jsonPostRequest = request({
method: 'POST',
host: 'localhost',
port: 8080,
path: '/api/',
headers: {'Content-Type': 'application/json'}
}, res => {
let chunks = ''
// Handle Response Chunk
res.on('data', chunk => (chunks += chunk))
// Handle Response Ended, print response body
res.on('end', () => console.log(chunks))
})
jsonPostRequest.write(requestBody)
jsonPostRequest.end()
I just started to learn nodejs with express framework.In my app there are two pages app.js and db.js..I need to post data from form and insert to register table
In db.js
var mysql = require('./node_modules/mysql');
var connection = mysql.createConnection({
host: '127.0.0.1',
user: 'root',
password: '',
database: 'nodeapp'
});
connection.connect(function (err) {
if (err)
throw err;
});
module.exports = connection;
// In my app.js page
var express = require('./lib/express');
var app = express();
var bodyParser = require('body-parser')
var db = require('/db');
app.get('/', function (req, res) {
res.sendFile('/NodeProj/views/' + 'index.html');
});
/** bodyParser.urlencoded(options)
* Parses the text as URL encoded data (which is how browsers tend to send form data from regular forms set to POST)
* and exposes the resulting object (containing the keys and values) on req.body
*/
app.use(bodyParser.urlencoded({
extended: true
}));
/**bodyParser.json(options)
* Parses the text as JSON and exposes the resulting object on req.body.
*/
app.use(bodyParser.json());
app.post('/process_form', function (req, res) {
var response = {
"firstname": req.body.fst_name,
"email": req.body.fst_email,
"password": req.body.fst_password
};
var query = connection.query('INSERT INTO register SET?',response,function(err,result){
if(err) throw err;
if(result) console.log(result);
});
res.end(JSON.stringify(response));
});
app.listen(8081);
But when I run the code I got the following error
Refference error: connection is not defined
Please help me .Thanks in advance.
As mentioned in the comments, you've called connection db.
So if you replace var db = require('/db'); with var connection = require('./db'); then your connection will be defined.