Pass data to the same page in express - node.js

Question

i want to pass data from server to the same page if there is an error in the POSTED data.
i have two routes , one route to display the contents and the other route for adding new content. i am using pug as view.
form for the new content is :
extends layout
block content
form(action="/create", method="POST")
h2= title
p
| Text :
input(type="text", name="text")
input(type="submit")
whenever i click the submit button the value in the input is posted
here's the node route.post() code :
router.post('/create' ,function(req,res,next){
if(req.body.text === ''){
res.send("empty")
}else{
contents.push(text: req.body.text )
res.redirect('/')
}
} )
currently if i submit the form without any input value , it will send "empty" msg in a blank page.
What I want is that if the input value is empty, rather than sending "empty" in a blank page i want to send "empty" msg to the same Form page and show anywhere.
like this :
thank you : ) ......

Answer 1

We must use a variable to indicate there is an error. For example:
View
extends layout
block content
form(action="/create", method="POST")
h2= title
p
| Text :
input(type="text", name="text")
input(type="submit")
h2= error
Controller
router.post('/create' ,function(req,res,next){
if(req.body.text === ''){
res.render("your_view_name_here", { error: "empty" })
}else{
contents.push(text: req.body.text )
res.redirect('/')
}
})