Fix for parsing port at log middleware

[spaparaju]

This PR fixes issue#: 4320

• I added CHANGELOG entry for this change.
• Change is not relevant to the end user.

Changes

Added check for : prior to splitting the port from the hostURL.

Verification

Tested on standalone, Kube. environments and did not observe parsing errors in the log files.

[yeya24]

Thanks for the fix.
This pr worth a unit test. Would you mind adding one?

[squat]

Looks good SriKrishna :) i just have small style suggestions

[bwplotka]

Nice!

Can we add more clear PR title? It does not tell much what exactly was changed to fix it.

[spaparaju]

Thanks for the fix.
This pr worth a unit test. Would you mind adding one?

Added a unit test to test with an URL that does not explicitly contain a port number.

[GiedriusS]

@spaparaju please fix the DCO:

Commit sha: 073971d, Author: Srikrishna Paparaju, Committer: Srikrishna Paparaju; Expected "Srikrishna Paparaju [email protected]", but got "Srikrishna Paparaju [email protected]".

https://github.com/thanos-io/thanos/pull/4348/checks?check_run_id=2861409152

[spaparaju]

/retest

[yeya24]

LGTM.

[ikonyeama]

Still seeing these errors in the logs after upgrading Thanos from 0.21.1 to 0.24.0
level=error ts=2022-01-08T07:52:08.191747835Z caller=http.go:48 component=rules protocol=http http.component=server msg="failed to parse host port for http log decision" err="address xyz.com: missing port in address". Am I missing something?