express.js - req.body? - node.js

I'm new to js,
I see this a lot in the code I'm reading
_.pick(req.body, ' ' , ' ')
What does req.body do?
And when can I say req.body.something?

req.body holds parameters that are sent up from the client as part of a POST request. See the API.
// POST user[name]=tobi&user[email]=tobi#learnboost.com
req.body.user.name
// => "tobi"
req.body.user.email
// => "tobi#learnboost.com"
// POST { "name": "tobi" }
req.body.name
// => "tobi"

(req.body, ' ' , ' ') --> here req is the parameter of your function and using this parameter your can access the properties over then url.
so look this example
suppose this is form
<form>
enter the name : <input type="text" name="name">
<button type ="submit"> submit </button>
</form>
so if you want to access the name -- which is filled by the user end.
so for this you can
do like this-> console.log(req.body.name); -- this will print the name (property) in console.

Related

Submitting a form from email ejs template and use the value in a middleware

I am sending an ejs email along some parameters (userId and email). Inside the email there is a form that should send this (userId) variable back to the server and should be used in a middleware. However, nodejs does not recognise the req.body...
The ejs form have an input with the value populated to be the userId and should be passed down to the action url...:
<form action="http://localhost:3000/api/allowUser" method="POST">
<!-- Here i passed the userId as a value and send to email-->
<input type="text" id="userId" name="userId" value="<%- userId %>">
<input type="submit" value="Allow user" />
</form>
This is the email received with the input value.
Outcome:
Now, the administrator is redirected to the success page by accessing the /allowUser endpoint. Here, I need to use the req.body.userId, but is undefined... I cannot have access even to req object...
exports.allowUser = async (req, res, next) => {
// NEED TO USE THE userId HERE
let {userId} = req.body; //Undefined
console.log(req.body); //empty object
res.render('success.ejs', {userId: userId});
}
The redirect function works, but the userId cannot be passed or used in the allowUser function.
However, if accessing the network tab in the success page I can see there the userId being present at every refresh. But still not being able to access the variable
anyone have any ideas please? Many thanks, Daniel
Hello i can see that your ejs form is correct,but in your req.body you should get userid like this way
let user_id=req.body.userId //userId name
// from ejs form
Then render success page
res.render("success",{userid:user_id});
//without .ejs in success page
Also i think your form action doesn't need the whole link,only the endpoint /allowuser
Make sure that your routes are correct,hope this will help you.Tell me again if problem still exists.

How to handle response in react

I am new to react. Currently I am working on creating a login screen. I have this code:
function login(e) {
fetch('/login')
.then(response => {
if(response === 'fail'){
return(SignIn());
}else{
return(Ide());
}
})
.then((proposals) => {
console.log(proposals);
this.setState({ proposals });
});
}
export default function SignIn() {
const classes = useStyles();
return (
<Container component="main" maxWidth="xs">
<CssBaseline />
<div className={classes.paper}>
<Avatar className={classes.avatar}>
</Avatar>
<Typography component="h1" variant="h5">
Sign in
</Typography>
<form className={classes.form} noValidate>
<TextField
variant="outlined"
margin="normal"
required
fullWidth
id="email"
label="Email Address"
name="email"
autoComplete="email"
autoFocus
/>
<TextField
variant="outlined"
margin="normal"
required
fullWidth
name="password"
label="Password"
type="password"
id="password"
autoComplete="current-password"
/>
<Button
type="submit"
fullWidth
onClick={login}
variant="contained"
color="primary"
className={classes.submit}
>
Sign In
</Button>
</form>
</div>
</Container>
);
And then the login handler
app.get('/login', (req, res, next) => {
const { email, password } = req.body;
console.log(email, password);
//User.find({email: })
});
But when I press the submit button, email and password both console log as undefined. How do I send information using react between the client and the server? Thank you in advance
Whenever you use fetch as a way to send info to an endpoint like '/login' above, the req.body needs to be added as part of the fetch call. To do this, people usually do
fetch('/login', {
body: (whatever you send in the form of one object)
});
The body passed in as the second argument can be then used as req.body in your code that console.logs it.
This is not advised though since GET commands usually do not have bodies passed along as the second argument. Usually POST and PUT commands have the body to make it easy to add and change data. What I recommend is do:
fetch('/login/' + email + '/' + password);
This allows for an email and username object to be a part of your url in for your backend to use. This is one of the ways that people do GET commands without passing in a body. With the new format, you should change the backend to be:
app.get('/login/:email/:password', (req, res) => {
const email = req.params.email;
const password = req.params.password;
console.log(email, password);
With :email and :password in the url, this lets you use req.params and then directly call each identifier as the last value.
Btw if you feel like the fetch call above looks messy with the + commands, you can instead do:
fetch(`/login/${email}/${password}`);
Which are Template Literals that make it easier to read code by adding the values directly into the string. (Note they use the ` key next to the 1 key not ' or ")
Also if you want more info on fetch commands, I advise to start with the MDM Documentation. This website is extremely helpful whenever you need to learn something about JS or other web languages.

req.body value undefined for form field value set by javascript function

I am building a node.js,express.js and passport.js app. Once logged into the profile I ask the user to click a button “Get Location” to get the users location.
Profile.ejs
<form action="/testform" method="post" >
<div class="form-group">
<input type="text" class="form-control" id="latVal" placeholder="latitude">
<input type="text" class="form-control" id="longVal" placeholder="longitude">
</div>
<button type = "submit" class="btn btn-warning btn-sm">Save</button>
</form>
<button type = "submit" class="btn btn-warning btn-sm" onclick="getLocation()">Get Location</button>
onclick the getLocation() function is called which is located in mapCall.js
function getLocation()
…
//call to showLocation()
}
function showLocation(position) {
…
document.getElementById("latVal").value = latitude;
document.getElementById("longVal").value = longitude;
}
showLocation() sets the values in the form to the latitude (id="latVal") and longitude (id="longVal") returned from the API call. The values appear in the form field. From here I want to save these values to the users profile data in MongoDB which I try to achieve in routes.js by click of the “Save” button which triggers the function below
app.post('/testform', isLoggedIn, function(req, res) {
user.findById(req.user.id, function(err,user) {
if(!user) {
req.flash('error', 'No accound found');
return res.redirect('/profile');
}
user.location.latitude = req.body.latVal;
user.location.longitude = req.body.longVal;
user.save(function(err){
res.redirect('/profile');
});
});
});
When I console.log req.body.latVal and req.body.longVal the value for these variables is undefined. Nothing is saved in the db.
In server.js I have
var bodyParser = require('body-parser');
app.use(bodyParser());
Upon looking into proposed solutions to req.body returning undefined I tried
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({ extended: false }));
I didn’t think adding the two lines above would work because the value returned by the API is not in JSON format. This did not work. I checked the typeof for latitude and longitude and it is a number. I am not sure why req.body is not picking up the value.
My initial guess was that app.post tries to read the value before the API can return a value in which case req.body.latVal would read an empty field. I added the save button to test that theory which also proved wrong.
The closest thing I found to my issue is this which was never resolved.
Any guidance is highly appreciated or perhaps even a better way to accomplish this will be great. The reason I have the form fields populate is because I couldn't think of another way to send the values from the frontend to the backend for saving.
Add the name attribute to your inputs.
<input type="text" class="form-control" id="latVal" placeholder="latitude" name="latVal">
<input type="text" class="form-control" id="longVal" placeholder="longitude" name="longVal">
EDIT: (from the comment)
You can do an AJAX call to your server after the getLocation() call.
function getLocation() {
///you get the lat and long
showLocation(position)
saveLocation(latitude, longitude)
.then(function(resp){
//do something with resp
})
}
function saveLocation(latitude, longitude) {
//we have native fetch in newer browsers, so
return fetch("/testform", {
method: "POST",
headers: {
"Content-Type": "application/json; charset=utf-8", //if this doesn't work use the below one
// "Content-Type": "application/x-www-form-urlencoded",
},
body: JSON.stringify({latitude,longitude}), // body data type must match "Content-Type" header
})
.then(response => response.json());
}
This is just an outline of what you can do. Extend this code to your needs.
You are correct in most parts ,You just have to replace ID with name.that is the only way nodejs will be able to locate to your input field

Express JS does not perform delete

PUGJS script
form(id="form1" action="/delete" method="POST")
input(type="submit",name=+item['id'] value="delete")
My ExpressJS code
router.post('/delete', function(req, res, next) {
var id = req.params("i");
console.log("i am 0")
MongoClient.connect(url, function(err, db) {
console.log("i am 1")
db.collection('books', function(err, book) {
db.collection.deleteOne( {_id: new mongodb.ObjectID(id)} );
console.log("i am 2")
if (err) {
throw err;
} else {
db.close();
res.redirect('/');
}
});
});
});
Trying to perform a delete request but it does not even print ("i am 0")
can not determine what's broken with the code
NPM response POST /delete 404 7.247 ms - 1202
When you see a 404 the root cause is definitely how you set up the routing. This code would be successfully called if it is in app.js/server.js (or whatever your root express file is), but a 404 means that you have placed it in a secondary file and are using another path in there somewhere.
With that said, you also have an issue with how your route is defined if you want to read a route parameter (which is what the first line of your route handler tries to do).
router.post('/delete/:i', function...
The form itself isn't passing any id though through name (or id). You could either pass the id through the url called:
action= "/delete?id=" + id
...and read this in your route handler using req.query.id or you could insert a hidden input in the form and read it using req.body.id.
Also, the form name attribute has been deprecated and should be replaced with id.
Then, it's important to note that pug is highly dependent on indentation. Your code as pasted will generate an empty form and a separate input field.
This:
form(id="form1" action="/delete" method="POST")
input(type="submit",name=+item['id'] value="delete")
Generates this HTML:
<form id="form1" action="/delete" method="POST"></form>
<input type="submit" name="itemId" value="delete">
If you change the pug template to this (note the two additional spaces on the input line):
form(id="form1" action="/delete" method="POST")
input(type="submit",name=+item['id'] value="delete")
You will get this, which should work as expected:
<form id="form1" action="/delete" method="POST">
<input type="submit" name="itemId" value="delete">
</form>
Then, there's the problem in your delete function where you're missing a callback.
db.collection.deleteOne( {_id: new mongodb.ObjectID(id)} );
You need to either add a promise or callback here otherwise your code will move straight to close the connection.

Get an html attribute in node.js

Say I have a button like
<form action="/action1" method ="post">
<button type="submit" id="button1"> Click Me </button>
</form>
I want to get a value stored in the attributes (in this case "id") and do something like this
app.post('/action1', function (req, res) {
var buttonId = req.id // this is the part I dont understand
});
how would I fill in the line
var buttonId =
Thank you
The posted data does not include the id attribute. You can set the name and/or the value attribute and those will be part of the POST request. e.g.
<button type="submit" name="button1">Click Me</button>
To get to the posted data in express look here: Express js form data

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