Node Express can't set session with post request - node.js

Question

I use node express 4.0 to implement a message code verify function.
I use session to store the msg code I send.
I set up the session middleware as dos said：
app.use(logger('dev'));
app.use(bodyParser.json());
app.use(bodyParser.urlencoded({
extended: false
}));
app.use(cookieParser());
app.use(session({secret:'ssssss'}));
app.use(express.static(path.join(__dirname, 'public')));
app.use('/uploads', express.static(path.join(__dirname, 'uploads/temp')));
but when I use post method get the msg code, I found that the session didn't set successfully.
Like this code below:
router.post('/msgCode', function(req, res) {
req.session.test = 'test';
// request send msg code api then response
}
when I repost this router I found that the req.session.test is undefined.
then I try this in another router:
router.get('/sendMsgTest', function(req, res) {
req.session.test = 'test';
res.json({
status:0
})
}
every time I request sendMsgTest, I can get req.session.test. And when I request another get method, I can get req.session.test value successfully.
So why is it my post method didn't work?

Answer 1

I had the same issue. I've been using fetch for requests and it does not send cookies by default, so I got different cookie ids for GET and POST requests. The solution was:
fetch(url, {
credentials: 'same-origin' // or 'include'
});
See https://developer.mozilla.org/en-US/docs/Web/API/Request/credentials for more info.

Answer 2

you just try the session.save() , and in express 4 you must mention "resave" ,"saveUninitialized"
var session = require('express-session');
app.use(session({secret: 'keyboard cat', resave: false, saveUninitialized: true,cookie: { path: '/', httpOnly: true, maxAge: 30 * 30000 },rolling: true}));
router.post('/savesession', function (req, res) {
req.session.user = 'user';
req.session.save()
res.json(req.session.user);
});
router.get('/getsession', function (req, res) {
res.json(req.session.user);
});

Answer 3

You don't mention how you're calling the POST route. Are you sending the session cookie along with the POST request? Also, what type of response is the POST method returning?
(in app.js)
var session = require('express-session');
app.use(session({
secret: 'sooper_secret',
resave: false,
saveUninitialized: false
}));
(in routes/index.js)
router.post('/post', function (req, res) {
req.session.test = 'test';
res.json({success: true});
});
router.get('/get', function (req, res) {
const results = {
sessionData: req.session.test || 'session data not found'
};
res.json(results);
});
(command line)
% curl -X POST localhost:3000/post --cookie-jar test.cookie
% {"success":true}
% curl localhost:3000/get --cookie test.cookie
% {"sessionData":"test"}