1639562700
Node js express login com exemplo de banco de dados MySQL; Neste tutorial, você aprenderá como criar um sistema de login no nó js + express js com banco de dados MySQL.
Este tutorial o ajudará passo a passo para criar um sistema de login no framework node js + express com banco de dados MySQL. E também; você aprenderá como manipular, manipular dados de formulário e conectar o banco de dados ao aplicativo usando sessão, analisador de corpo, validador.
Execute o seguinte comando no terminal para instalar o aplicativo express js:
express --view=ejs loginSystem
Em seguida, abra a configuração do loginSystem com qualquer editor de texto. E use o seguinte comando para inserir seus diretórios de aplicativo loginSystem , então abra seu cmd e execute o seguinte comando:
cd loginSystem
A estrutura do seu aplicativo node express js se parece com:
Em seguida, você precisa instalar alguns pacakges necessários, então abra novamente seu cmd e execute os seguintes comandos:
npm install
npm install express-flash --save
npm install express-session --save
npm install express-validator --save
npm install method-override --save
npm install mysql --save
npm install http-errors-enhanced --save
flash expresso
Flash é uma extensão do connect-flash com a capacidade de definir uma mensagem flash e renderizá-la sem redirecionar a solicitação.
Neste nó, o flash expresso do tutorial do js mysql crud é usado para exibir uma mensagem de aviso, erro e informação
sessão expressa
Express-session é usada para fazer uma sessão como no PHP. Neste tutorial do js mysql crud do nó, a sessão é necessária como o requisito expresso do flash expresso.
express-validator
O validador expresso é usado para validar os dados do formulário e é fácil de usar. express-validator forma altamente eficaz e eficiente de acelerar a criação de aplicativos.
substituição de método
O NPM é usado para executar um método DELETE e PUT a partir de um formulário HTML. Em vários navegadores da Web, apenas os métodos GET e POST são compatíveis.
MySQL
Driver para conectar node.js com MySQL
Antes de conectar o banco de dados ao seu aplicativo, crie uma tabela no seu banco de dados usando a seguinte consulta SQL:
CREATE DATABASE IF NOT EXISTS `nodelogin` DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci;
USE `nodelogin`;
CREATE TABLE IF NOT EXISTS `users` (
`id` int(11) NOT NULL,
`name` varchar(50) NOT NULL,
`password` varchar(255) NOT NULL,
`email` varchar(100) NOT NULL
) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8;
INSERT INTO `users` (`id`, `name`, `password`, `email`) VALUES (1, 'test', 'test', 'test@test.com');
ALTER TABLE `users` ADD PRIMARY KEY (`id`);
ALTER TABLE `users` MODIFY `id` int(11) NOT NULL AUTO_INCREMENT,AUTO_INCREMENT=2;
Em seguida, você precisa criar uma pasta chamada lib e criar um novo nome de arquivo db.js dentro da pasta lib .
Observe que este arquivo é usado para conectar seu aplicativo node express js ao banco de dados MySQL.
lib / db.js
Atualize o código de conexão do MySQL em seu arquivo db.js :
var mysql=require('mysql');
var connection=mysql.createConnection({
host:'localhost',
user:'root',
password:'your password',
database:'nodelogin'
});
connection.connect(function(error){
if(!!error){
console.log(error);
}else{
console.log('Connected!:)');
}
});
module.exports = connection;
Nesta etapa, você precisa incluir todos os pacotes no arquivo app.js cujo instalado acima e também inicializar a sessão neste arquivo.
Portanto, vá para o arquivo app.js e atualize o seguinte código:
var createError = require('http-errors');
var express = require('express');
var path = require('path');
var cookieParser = require('cookie-parser');
var logger = require('morgan');
var expressValidator = require('express-validator');
var flash = require('express-flash');
var session = require('express-session');
var bodyParser = require('body-parser');
var mysql = require('mysql');
var connection = require('./lib/db');
var indexRouter = require('./routes/index');
var authRouter = require('./routes/auth');
var app = express();
// view engine setup
app.set('views', path.join(__dirname, 'views'));
app.set('view engine', 'ejs');
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: true }));
app.use(cookieParser());
app.use(express.static(path.join(__dirname, 'public')));
app.use(session({
secret: '123456cat',
resave: false,
saveUninitialized: true,
cookie: { maxAge: 60000 }
}))
app.use(flash());
app.use(expressValidator());
app.use('/', indexRouter);
app.use('/auth', authRouter);
// catch 404 and forward to error handler
app.use(function(req, res, next) {
next(createError(404));
});
// error handler
app.use(function(err, req, res, next) {
// set locals, only providing error in development
res.locals.message = err.message;
res.locals.error = req.app.get('env') === 'development' ? err : {};
// render the error page
res.status(err.status || 500);
res.render('error');
});
// port must be set to 3000 because incoming http requests are routed from port 80 to port 8080
app.listen(3000, function () {
console.log('Node app is running on port 3000');
});
module.exports = app;
Nesta etapa, você precisa criar um nome de arquivo de rota auth.js dentro da pasta de rotas .
Em seguida, atualize as seguintes rotas em seu arquivo routes / auth.js :
var express = require('express');
var router = express.Router();
var connection = require('../lib/db');
//display login page
router.get('/', function(req, res, next){
// render to views/user/add.ejs
res.render('auth/login', {
title: 'Login',
email: '',
password: ''
})
})
//display login page
router.get('/login', function(req, res, next){
// render to views/user/add.ejs
res.render('auth/login', {
title: 'Login',
email: '',
password: ''
})
})
//authenticate user
router.post('/authentication', function(req, res, next) {
var email = req.body.email;
var password = req.body.password;
connection.query('SELECT * FROM users WHERE email = ? AND password = ?', [email, password], function(err, rows, fields) {
if(err) throw err
// if user not found
if (rows.length <= 0) {
req.flash('error', 'Please correct enter email and Password!')
res.redirect('/login')
}
else { // if user found
// render to views/user/edit.ejs template file
req.session.loggedin = true;
req.session.name = name;
res.redirect('/home');
}
})
})
//display home page
router.get('/home', function(req, res, next) {
if (req.session.loggedin) {
res.render('auth/home', {
title:"Dashboard",
name: req.session.name,
});
} else {
req.flash('success', 'Please login first!');
res.redirect('/login');
}
});
// Logout user
router.get('/logout', function (req, res) {
req.session.destroy();
req.flash('success', 'Login Again Here');
res.redirect('/login');
});
module.exports = router;
Nesta etapa, você precisa criar uma pasta com o nome Auth . Portanto, vá para a pasta de visualizações em seu aplicativo e crie a pasta Auth .
Dentro da pasta Auth, você precisa criar dois arquivos de visualizações. O arquivo de visualizações é o seguinte:
Agora, abra seu arquivo login.ejs e atualize o seguinte código em seu arquivo:
<!DOCTYPE html>
<html>
<head>
<title><%= title %></title>
<script src="https://code.jquery.com/jquery-3.4.1.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css">
</head>
<body>
<% if (messages.error) { %>
<p style="color:red"><%- messages.error %></p>
<% } %>
<% if (messages.success) { %>
<p style="color:green"><%- messages.success %></p>
<% } %>
<form action="/auth/authentication" method="post" name="form1">
<div class="form-group">
<label for="exampleInputEmail1">Email</label>
<input type="email" name="email" class="form-control" id="email" aria-describedby="emailHelp" placeholder="Enter email" value="">
</div>
<div class="form-group">
<label for="exampleInputEmail1">Password</label>
<input type="password" name="password" class="form-control" id="password" aria-describedby="emailHelp" placeholder="*********" value="">
</div>
<input type="submit" class="btn btn-primary" value="Add">
</form>
</body>
</html>
Este arquivo login.ejs contém o formulário de login.
Em seguida, abra seu arquivo home.ejs e atualize o seguinte código em seu arquivo:
<!DOCTYPE html>
<html>
<head>
<title><%= title %></title>
<script src="https://code.jquery.com/jquery-3.4.1.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.3/umd/popper.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.1.3/css/bootstrap.min.css">
</head>
<body>
<div class="container">
<% if (messages.error) { %>
<p style="color:red"><%- messages.error %></p>
<% } %>
<% if (messages.success) { %>
<p style="color:green"><%- messages.success %></p>
<% } %>
<div class="card">
<div class="card-header">
Dashboard <b><%= name %></b>
</div>
<div class="card-body">
<h5 class="card-title">Welcome</h5>
<p class="card-text">You have successfully login</p>
<a href="auth/logout" class="btn btn-primary">Logout</a>
</div>
</div>
</div>
</body>
</html>
Você pode usar o seguinte comando para executar o servidor de desenvolvimento:
//run the below command
npm start
after run this command open your browser and hit
http://127.0.0.1:3000/auth
OR
http://127.0.0.1:3000/auth/login
Exemplo de login expresso do nó js com tutorial do MySQL. Você aprendeu como criar um sistema de login no node js usando o framework express js com MySQL db.
1632537859
Not babashka. Node.js babashka!?
Ad-hoc CLJS scripting on Node.js.
Experimental. Please report issues here.
Nbb's main goal is to make it easy to get started with ad hoc CLJS scripting on Node.js.
Additional goals and features are:
Nbb requires Node.js v12 or newer.
CLJS code is evaluated through SCI, the same interpreter that powers babashka. Because SCI works with advanced compilation, the bundle size, especially when combined with other dependencies, is smaller than what you get with self-hosted CLJS. That makes startup faster. The trade-off is that execution is less performant and that only a subset of CLJS is available (e.g. no deftype, yet).
Install nbb
from NPM:
$ npm install nbb -g
Omit -g
for a local install.
Try out an expression:
$ nbb -e '(+ 1 2 3)'
6
And then install some other NPM libraries to use in the script. E.g.:
$ npm install csv-parse shelljs zx
Create a script which uses the NPM libraries:
(ns script
(:require ["csv-parse/lib/sync$default" :as csv-parse]
["fs" :as fs]
["path" :as path]
["shelljs$default" :as sh]
["term-size$default" :as term-size]
["zx$default" :as zx]
["zx$fs" :as zxfs]
[nbb.core :refer [*file*]]))
(prn (path/resolve "."))
(prn (term-size))
(println (count (str (fs/readFileSync *file*))))
(prn (sh/ls "."))
(prn (csv-parse "foo,bar"))
(prn (zxfs/existsSync *file*))
(zx/$ #js ["ls"])
Call the script:
$ nbb script.cljs
"/private/tmp/test-script"
#js {:columns 216, :rows 47}
510
#js ["node_modules" "package-lock.json" "package.json" "script.cljs"]
#js [#js ["foo" "bar"]]
true
$ ls
node_modules
package-lock.json
package.json
script.cljs
Nbb has first class support for macros: you can define them right inside your .cljs
file, like you are used to from JVM Clojure. Consider the plet
macro to make working with promises more palatable:
(defmacro plet
[bindings & body]
(let [binding-pairs (reverse (partition 2 bindings))
body (cons 'do body)]
(reduce (fn [body [sym expr]]
(let [expr (list '.resolve 'js/Promise expr)]
(list '.then expr (list 'clojure.core/fn (vector sym)
body))))
body
binding-pairs)))
Using this macro we can look async code more like sync code. Consider this puppeteer example:
(-> (.launch puppeteer)
(.then (fn [browser]
(-> (.newPage browser)
(.then (fn [page]
(-> (.goto page "https://clojure.org")
(.then #(.screenshot page #js{:path "screenshot.png"}))
(.catch #(js/console.log %))
(.then #(.close browser)))))))))
Using plet
this becomes:
(plet [browser (.launch puppeteer)
page (.newPage browser)
_ (.goto page "https://clojure.org")
_ (-> (.screenshot page #js{:path "screenshot.png"})
(.catch #(js/console.log %)))]
(.close browser))
See the puppeteer example for the full code.
Since v0.0.36, nbb includes promesa which is a library to deal with promises. The above plet
macro is similar to promesa.core/let
.
$ time nbb -e '(+ 1 2 3)'
6
nbb -e '(+ 1 2 3)' 0.17s user 0.02s system 109% cpu 0.168 total
The baseline startup time for a script is about 170ms seconds on my laptop. When invoked via npx
this adds another 300ms or so, so for faster startup, either use a globally installed nbb
or use $(npm bin)/nbb script.cljs
to bypass npx
.
Nbb does not depend on any NPM dependencies. All NPM libraries loaded by a script are resolved relative to that script. When using the Reagent module, React is resolved in the same way as any other NPM library.
To load .cljs
files from local paths or dependencies, you can use the --classpath
argument. The current dir is added to the classpath automatically. So if there is a file foo/bar.cljs
relative to your current dir, then you can load it via (:require [foo.bar :as fb])
. Note that nbb
uses the same naming conventions for namespaces and directories as other Clojure tools: foo-bar
in the namespace name becomes foo_bar
in the directory name.
To load dependencies from the Clojure ecosystem, you can use the Clojure CLI or babashka to download them and produce a classpath:
$ classpath="$(clojure -A:nbb -Spath -Sdeps '{:aliases {:nbb {:replace-deps {com.github.seancorfield/honeysql {:git/tag "v2.0.0-rc5" :git/sha "01c3a55"}}}}}')"
and then feed it to the --classpath
argument:
$ nbb --classpath "$classpath" -e "(require '[honey.sql :as sql]) (sql/format {:select :foo :from :bar :where [:= :baz 2]})"
["SELECT foo FROM bar WHERE baz = ?" 2]
Currently nbb
only reads from directories, not jar files, so you are encouraged to use git libs. Support for .jar
files will be added later.
The name of the file that is currently being executed is available via nbb.core/*file*
or on the metadata of vars:
(ns foo
(:require [nbb.core :refer [*file*]]))
(prn *file*) ;; "/private/tmp/foo.cljs"
(defn f [])
(prn (:file (meta #'f))) ;; "/private/tmp/foo.cljs"
Nbb includes reagent.core
which will be lazily loaded when required. You can use this together with ink to create a TUI application:
$ npm install ink
ink-demo.cljs
:
(ns ink-demo
(:require ["ink" :refer [render Text]]
[reagent.core :as r]))
(defonce state (r/atom 0))
(doseq [n (range 1 11)]
(js/setTimeout #(swap! state inc) (* n 500)))
(defn hello []
[:> Text {:color "green"} "Hello, world! " @state])
(render (r/as-element [hello]))
Working with callbacks and promises can become tedious. Since nbb v0.0.36 the promesa.core
namespace is included with the let
and do!
macros. An example:
(ns prom
(:require [promesa.core :as p]))
(defn sleep [ms]
(js/Promise.
(fn [resolve _]
(js/setTimeout resolve ms))))
(defn do-stuff
[]
(p/do!
(println "Doing stuff which takes a while")
(sleep 1000)
1))
(p/let [a (do-stuff)
b (inc a)
c (do-stuff)
d (+ b c)]
(prn d))
$ nbb prom.cljs
Doing stuff which takes a while
Doing stuff which takes a while
3
Also see API docs.
Since nbb v0.0.75 applied-science/js-interop is available:
(ns example
(:require [applied-science.js-interop :as j]))
(def o (j/lit {:a 1 :b 2 :c {:d 1}}))
(prn (j/select-keys o [:a :b])) ;; #js {:a 1, :b 2}
(prn (j/get-in o [:c :d])) ;; 1
Most of this library is supported in nbb, except the following:
:syms
.-x
notation. In nbb, you must use keywords.See the example of what is currently supported.
See the examples directory for small examples.
Also check out these projects built with nbb:
See API documentation.
See this gist on how to convert an nbb script or project to shadow-cljs.
Prequisites:
To build:
bb release
Run bb tasks
for more project-related tasks.
Download Details:
Author: borkdude
Download Link: Download The Source Code
Official Website: https://github.com/borkdude/nbb
License: EPL-1.0
#node #javascript
1616671994
If you look at the backend technology used by today’s most popular apps there is one thing you would find common among them and that is the use of NodeJS Framework. Yes, the NodeJS framework is that effective and successful.
If you wish to have a strong backend for efficient app performance then have NodeJS at the backend.
WebClues Infotech offers different levels of experienced and expert professionals for your app development needs. So hire a dedicated NodeJS developer from WebClues Infotech with your experience requirement and expertise.
So what are you waiting for? Get your app developed with strong performance parameters from WebClues Infotech
For inquiry click here: https://www.webcluesinfotech.com/hire-nodejs-developer/
Book Free Interview: https://bit.ly/3dDShFg
#hire dedicated node.js developers #hire node.js developers #hire top dedicated node.js developers #hire node.js developers in usa & india #hire node js development company #hire the best node.js developers & programmers
1622719015
Front-end web development has been overwhelmed by JavaScript highlights for quite a long time. Google, Facebook, Wikipedia, and most of all online pages use JS for customer side activities. As of late, it additionally made a shift to cross-platform mobile development as a main technology in React Native, Nativescript, Apache Cordova, and other crossover devices.
Throughout the most recent couple of years, Node.js moved to backend development as well. Designers need to utilize a similar tech stack for the whole web project without learning another language for server-side development. Node.js is a device that adjusts JS usefulness and syntax to the backend.
Node.js isn’t a language, or library, or system. It’s a runtime situation: commonly JavaScript needs a program to work, however Node.js makes appropriate settings for JS to run outside of the program. It’s based on a JavaScript V8 motor that can run in Chrome, different programs, or independently.
The extent of V8 is to change JS program situated code into machine code — so JS turns into a broadly useful language and can be perceived by servers. This is one of the advantages of utilizing Node.js in web application development: it expands the usefulness of JavaScript, permitting designers to coordinate the language with APIs, different languages, and outside libraries.
Of late, organizations have been effectively changing from their backend tech stacks to Node.js. LinkedIn picked Node.js over Ruby on Rails since it took care of expanding responsibility better and decreased the quantity of servers by multiple times. PayPal and Netflix did something comparative, just they had a goal to change their design to microservices. We should investigate the motivations to pick Node.JS for web application development and when we are planning to hire node js developers.
The principal thing that makes Node.js a go-to environment for web development is its JavaScript legacy. It’s the most well known language right now with a great many free devices and a functioning local area. Node.js, because of its association with JS, immediately rose in ubiquity — presently it has in excess of 368 million downloads and a great many free tools in the bundle module.
Alongside prevalence, Node.js additionally acquired the fundamental JS benefits:
In addition, it’s a piece of a well known MEAN tech stack (the blend of MongoDB, Express.js, Angular, and Node.js — four tools that handle all vital parts of web application development).
This is perhaps the most clear advantage of Node.js web application development. JavaScript is an unquestionable requirement for web development. Regardless of whether you construct a multi-page or single-page application, you need to know JS well. On the off chance that you are now OK with JavaScript, learning Node.js won’t be an issue. Grammar, fundamental usefulness, primary standards — every one of these things are comparable.
In the event that you have JS designers in your group, it will be simpler for them to learn JS-based Node than a totally new dialect. What’s more, the front-end and back-end codebase will be basically the same, simple to peruse, and keep up — in light of the fact that they are both JS-based.
There’s another motivation behind why Node.js got famous so rapidly. The environment suits well the idea of microservice development (spilling stone monument usefulness into handfuls or many more modest administrations).
Microservices need to speak with one another rapidly — and Node.js is probably the quickest device in information handling. Among the fundamental Node.js benefits for programming development are its non-obstructing algorithms.
Node.js measures a few demands all at once without trusting that the first will be concluded. Many microservices can send messages to one another, and they will be gotten and addressed all the while.
Node.js was worked in view of adaptability — its name really says it. The environment permits numerous hubs to run all the while and speak with one another. Here’s the reason Node.js adaptability is better than other web backend development arrangements.
Node.js has a module that is liable for load adjusting for each running CPU center. This is one of numerous Node.js module benefits: you can run various hubs all at once, and the environment will naturally adjust the responsibility.
Node.js permits even apportioning: you can part your application into various situations. You show various forms of the application to different clients, in light of their age, interests, area, language, and so on. This builds personalization and diminishes responsibility. Hub accomplishes this with kid measures — tasks that rapidly speak with one another and share a similar root.
What’s more, Node’s non-hindering solicitation handling framework adds to fast, letting applications measure a great many solicitations.
Numerous designers consider nonconcurrent to be one of the two impediments and benefits of Node.js web application development. In Node, at whatever point the capacity is executed, the code consequently sends a callback. As the quantity of capacities develops, so does the number of callbacks — and you end up in a circumstance known as the callback damnation.
In any case, Node.js offers an exit plan. You can utilize systems that will plan capacities and sort through callbacks. Systems will associate comparable capacities consequently — so you can track down an essential component via search or in an envelope. At that point, there’s no compelling reason to look through callbacks.
So, these are some of the top benefits of Nodejs in web application development. This is how Nodejs is contributing a lot to the field of web application development.
I hope now you are totally aware of the whole process of how Nodejs is really important for your web project. If you are looking to hire a node js development company in India then I would suggest that you take a little consultancy too whenever you call.
Good Luck!
#node.js development company in india #node js development company #hire node js developers #hire node.js developers in india #node.js development services #node.js development
1616839211
Top organizations and start-ups hire Node.js developers from SISGAIN for their strategic software development projects in Illinois, USA. On the off chance that you are searching for a first rate innovation to assemble a constant Node.js web application development or a module, Node.js applications are the most appropriate alternative to pick. As Leading Node.js development company, we leverage our profound information on its segments and convey solutions that bring noteworthy business results. For more information email us at hello@sisgain.com
#node.js development services #hire node.js developers #node.js web application development #node.js development company #node js application
React Interview Questions & Answers
1625631360
Today we are going to explore the basic usage of Express-FileUpload. In addition to this, I will show you how you can save/update a user record with a profile image that you can upload.
Chapters:
0:00 Introduction:
1:16 NPM Project Setup
3:54 Creating Express Server
5:51 Setting up Layouts & Routes
9:46 Express Upload Form
21:50 User Card
33:40 Database
52:05 Ending
#node.js #express #express-fileupload #express-handlebars #mysql #upload and store images