Session lost after redirect - node.js

Question

I use fetch() to send a post request for logon,
after server validation, I use req.session.account = account[0]; to save the account information to the session and return a redirect URL,
But after the redirect, the account information in the session is lost, why is that?

Answer 1

If you would have some example code, that would help us track down the problem. My first idea would be to make sure express-session is properly configured:
var app = express();
var session = require('express-session');
app.use(session({
secret: 'ibfiyegfiyegfe' // Secret is a required option.
}));
For futher configuration options, see the express-session repository.
EDIT: Based on the additional information, I'm guessing you have express-session configured to also use cookies for managing the sessions. What this means, is that for every HTTP request Express sends a response back that includes a cookie. jQuery based AJAX calls will ignore the response cookie however, which causes consecutive requests to Express to look as if you never logged in. To allow saving the cookie when performing AJAX requests with jQuery, use the xhrFields field to enable withCredentials:
$.ajax({
url: "http://....",
type: "POST",
xhrFields: {
withCredentials: true
},
data: {username: username, password: password},
success: function(responseBody) {
console.log("success!");
},
error: function(responseBody) {
console.log("error!");
}
});
Hope this helps.

Answer 2

Sorry to everyone, I don't making the question clear.
I use the fetch() method send a request to logon.
fetch('/logon', {
method: 'post',
headers: {
'Accept': 'application/json',
'Content-Type': 'application/json'
},
body: JSON.stringify({
account: account,
password: password
})
}).then(function(response){
return response.json();
}).then(function(json){
if(json.success == 1){
window.location.href = json.redirecturl;
}else{
indexDispatcher.dispatch({
actionType: 'logonFaild',
errorInfo: json.msg
});
}
});
And the server's response is just simple JSON:
if (err) {
consoloe.log(err);
} else {
req.session.account = account[0]; //save account to session
var redirecturl = '/team/' + team[0].id;
console.log("account添加到session了");
res.json({
success: 1,
redirecturl: redirecturl
});
}
But when the client get the redirecturl and redirect, the account data is lost,so it will occur a TypeError: Cannot read property 'id' of undefined(id is saved in req.session.account).
But when I use jquery $.ajax relpace fetch, it works well. I don't know the reason.

Answer 3

I had the same experience like you hundreds of times which I finally found the problem. You don't need to worry if cookies enable or disable.
You just have to re-declare parts of your scripts (variables-the data which you want to display) in a if else condition.
Just redeclare the same thing using !isset and then else with the same variables mentioned twice in the if else condition, if you understand what i mean.
It will call back the same variables over and over. And make sure start session is above the page. no need to worry about headers or white lines, it has actually nothing to do with it.
I've tried it a million times. You don't need to bother using ajax etc. PHP can do almost everything. cheerio.