[change] Allowed showing failure messages coming from captive portal #604

[praptisharma28]

…#604

Closes #604

Checklist

• I have read the OpenWISP Contributing Guidelines.
• I have manually tested the changes proposed in this pull request.
• I have written new test cases for new code and/or updated existing tests for changes to existing code.
• I have updated the documentation.

Reference to Existing Issue

Closes #604 .

Description of Changes

• Added captive-portal-handler.js to handle authentication failure detection and error messaging.
• When a captive portal authentication fails, it redirects back to the login page.

Also:

• By changing to:

import LoginComponent from "../login";

• We're getting the default export (the connected component) and there's no ambiguity about which version we're using as I was getting ESLint error

[nemesifier]

Sorry for the wait @praptisharma28, this has been buried under a pile of open PRs.

What steps can we do to manually test this?

Can you add at least one screenshot to the PR description or to a reply here please?

See my comment below.

[nemesifier]

I don't understand where this LoginComponent is coming from. Is this some naming convention in react or what? I can't see the definition of this class.

[praptisharma28]

#838 (comment)

@nemesifier here I have mentioned that I was getting an ESlint error, but what error in particular, I don't remember as it's been long. Got a new laptop hence need to set it up again and check, will let you know today itself.