Using express flash does not trigger a session update

[zbyte64]

The following happens in express 4:

req.flash('error', error.toString());
assert(req.session.isChanged == false)
req.session.foo = req.session.flash;
assert(req.session.isChanged == true)

But even doing that doesn't persist the data, both foo and flash get serialized as empty arrays. But if I set foo manually to an array or object then that does work.

[dougwilson]

Is it possible to provide a full test app I can run to reproduce the issue? That way I can attach a debugger to see what's happening. Otherwise, you're welcome to make a PR :)

[zbyte64]

I will whip up a failing test.

[dougwilson]

Cool, also would be helpful if you provided the following version in the meantime to help me work in parallel: version of Node.js, version of express flash, version of this module.

[zbyte64]

Forked this project and wrote an integration test using connect-flash:

https://github.com/zbyte64/cookie-session/blob/flash-message-fail/test/flash_test.js

I think I made some mistake because I can see in the view that properly retrieves the prior flash messages but weird stuff happens when I try to send it back to the client (empty response when sending a non-empty string, 500 if I don't stringify).

The package.json of the project experiencing the issue: https://github.com/zbyte64/project-cms-backend/blob/postgres/package.json ; using node v6.4

[dougwilson]

I'm not seeing any issue with this module in your test, unless I'm missing something?

[zbyte64]

The test fails:

  1) Cookie Session with flash message should persist:

      Uncaught AssertionError: {} deepEqual { info: [ 'hello world' ] }
      + expected - actual

      -{}
      +{
      +  "info": [
      +    "hello world"
      +  ]
      +}

[dougwilson]

Yea, but res.body has nothing to do with this module. What if you move the assert into the server side and test what is in req.session?

[dougwilson]

If you can please put together a pull request with a potential fix to this module, that would probably be ideal, because I'm not sure I see any issue based on that test, but again, I may be missing something :(

[zbyte64]

You're right, this is an issue outside of cookie-session (connect?).

[dougwilson]

So to add, I had to heavily modify your test just to get it to run for me. Just cloning it, npm install + npm test gave me the following error:

$ npm test

> cookie-session@2.0.0-alpha.1 test C:\cs-test\cookie-session
> mocha --check-leaks --reporter spec --bail test/



  Cookie Session with flash message
    1) should Set-Cookie


  0 passing (25ms)
  1 failing

  1) Cookie Session with flash message should Set-Cookie:
     Uncaught TypeError: Cannot read property 'header' of undefined
      at Test.<anonymous> (C:\cs-test\cookie-session\test\flash_test.js:25:21)
      at Test.assert (C:\cs-test\cookie-session\node_modules\supertest\lib\test.js:156:6)
      at Server.assert (C:\cs-test\cookie-session\node_modules\supertest\lib\test.js:127:12)
      at net.js:1277:10



npm ERR! Test failed.  See above for more details.

[dougwilson]

On https://github.com/jaredhanson/connect-flash I only see mentions about using it on Express 3.x. Are you sure it even works on Connect?

[zbyte64]

Hmm, title does mention connect at the top, but given it hasn't been updated in 4 years....
(Flash message middleware for Connect and Express.)

[dougwilson]

@zbyte64 does it sound like you are experiencing this bug? jaredhanson/connect-flash#22

[zbyte64]

Possibly, but not even error type is working for me.

[dougwilson]

Hi @zbyte64 your test you have above passes without issue if you add res.setHeader('Content-Type', 'application/json'); between lines 38 and 39. The reason your req.body was {} is because supertest didn't know it was JSON to parse without a Content-Type header.

[zbyte64]

Thank you.

I ended up using req-flash ( maximilianschmitt/req-flash ) and it works.