Option to save session before sending response

Looks like fix for https://github.com/expressjs/session/issues/61 (https://github.com/expressjs/session/commit/901c8e062c8789d3963ebe175a75d25d3c229245) is causing some wired race condition. In my usecase req.session.save is calling also encrypting the data before storing. And usually it takes more little longer than non-encrypted version. Because of the async nature of session save the next request is starting most of the time before the save is complete. And this next request is fetching the old version of session. Is there any possibility to add some flag to control the async/sync session save or any other solution?

[dougwilson]

just in case you’re not aware and feel like you have to wait on me, there is a work-around, which is to call req.session.save yourself and respond within that callback. for example

app.post('/', function (req, res, next) {
  // do stuff
  req.session.email = email
  req.session.save(function (err) {
    if (err) return next(err)
    res.render('page')
  })
})

[mjquito]

I still have the same issue as @skoranga was having it. The res.session.save() is saving twice. I’m using “express”: “4.16.2”, “express-session”: “1.15.6”. I really need help!

I’m saving my sessions on files, I’m using the session-file-store. The problem I’m trying to solve is that when I call “res.redirect(‘/’)”, I noticed in the “./express-session/index.js”, the res.end() gets ran and inside of that, the following gets ran

...
if (shouldSave(req)) {
        req.session.save(function onsave(err) {
          if (err) {
            defer(next, err);
          }

          writeend();
        });
...

And then the req.session.save runs asynchronously which then the redirection to \ starts happening and the session gets loaded BUT the req.session.save hasn’t finished saving the session in the file which then causes to load the old or previous state of the session. I used the suggested workaround (see below) of calling req.session.save before the redirecting

app.post('/', function (req, res, next) {
  // do stuff
  req.session.email = email
  req.session.save(function (err) {
    if (err) return next(err)
    res.render('page')
  })
})

And it works, but, it is calling twice to the req.session.save which is a no no. I really need help.