sign_in template form input redirect-url value is not updating as expected

[sreeharikmarar]

The use case for this change is, suppose oauth2_proxy is running on https://companydomain/dashboard , after successful authentication oauth2_proxy is not redirecting back to /dashboardwhere the request has started.

The reason for this behavior is redirect-url config option is not updating sign_in template "{{.Redirect}}" value as expected because of this check.

pull request for this fix had already raised but seems like its not merged yet.

Other option is to update the hidden field value of sign_in template input form with window.location.pathname so that after authentication, oauth2_proxy returns the request back to the same redirect url which mentioned in the form input.

pull request for sign_in template script changes