Fix: Validate headless and host options

[ilyabe]

Fixes #2575

Based on the discussion in #2610, validates the --headless and --host options.

• If --headless is passed, then --host is required
• If --host value doesn't include protocol, an error message is printed
• Updated all tests that had --headless without --host
• Added tests for the new error messages

These changes are only for the CLI. I'll make a separate PR for the webui.

If there's a better approach or anything to improve, I'm happy to.

[cyberw]

If --headless is passed, then --host is required

--host should not be required, because it can also be set on the User class. Lets just validate it if it is set,

Another problem is, what if it is not an http test at all? Maybe this solution is more problematic than I thought...

[ilyabe]

what if it is not an http test at all?

Then this is trickier. We could have a list of supported protocols (e.g. http, https, ftp, ssh, irc, etc.) but that might be too limiting? We could check that :// is in the host but I'm not sure all protocols specify a :// syntax. Maybe things are fine as is?

[ilyabe]

I updated the PR with one more approach. It uses urllib's urlparse to check that the parsed host has a scheme value. Just another option. If there are any issues with this, let me know :)

[cyberw]

what if it is not an http test at all?

Then this is trickier. We could have a list of supported protocols (e.g. http, https, ftp, ssh, irc, etc.) but that might be too limiting? We could check that :// is in the host but I'm not sure all protocols specify a :// syntax. Maybe things are fine as is?

I wouldnt necessarily call it "fine" :) but the current design makes it really hard to fix :-/

I wonder... Perhaps HttpUser could validate its host attribute on initialization and stop the test if it is not a valid prefix? (probably we should allow None, but that is not the key issue) Or maybe throwing an exception is enough to stop the user from being spawned. I dont really have time to explore how feasible that would be, but that way different Users can use different schemes.

[github-actions]

This PR was closed because it has been stalled for 10 days with no activity.