Return the auth challenge in the WWW-Authenticate when auth fails

[KeesV]

Fixes / New Feature

Perform Challenge on failed authentication, and return the generated WWW-Authenticate header in the upstream response.

Proposed Changes

• In AuthenticationMiddleware.cs: perform a challenge whenever authentication fails. This generates a WWW-Authenticate header on the response.
• It seems that the httpContext.Response that is available in AuthenticationMiddleware.cs is recreated/overwritten further down the pipeline, so we need to preserve the generated WWW-Authenticate header somewhere. For now, I've put it in the httpContext.Items (suggestions on how to do this in a better way are highly appreciated).
• Re-apply the WWW-Authenticate header on the response in ResponderMiddleware.cs.

[arnaulddumez]

Same problem for Access-Control-Allow-Origin ??

[raman-m]

Hi Kees!
Thanks for your interest in Ocelot!

Could you Sync fork please? So, your develop branch is outdated!

[raman-m]

The feature branch has been rebased onto ThreeMammals:develop!

@KeesV
Your develop branch in your fork is too old!
It seems building pipeline cannot start because your fork repo is old.

Could you Sync fork please? The develop branch will be updated by top commits!
Could you add me as collaborator to your forked repo please?

[raman-m]

@KeesV
Thanks for the great PR!
Is the PR related to some issue in backlog?

[KeesV]

hey @raman-m! Thanks for revitalizing this PR. It's great to see some activity here.
I've synced my fork and added you as a contributor there, should you want to make any changes.
I don't think there's any issue in the backlog for this PR as of now.

[raman-m]

CircleCI status: pull/1387
I don't see any jobs/pipelines for your feature branch.
So, building of feature branch cannot start for a some reason. It is strange!
It seems you need to re-fork the repo because of some old repo state... I believe, re-forking should help to recover the building pipeline.
But before doing that, make a file backup, or it is better just to make git diff patch please:

git diff commit1..commit2 > ../pull-1387.patch

After that for new fork, and new feature branch (base is develop) you need just to apply the patch:

git apply ../pull-1387.patch

Git recipe was taken from here: Stack Overflow | Create patch or diff file from git repository and apply it to another different git repository