I think I found two errors in the Issue Tracker project source code:
- views/index.html at line 62
<form id="testForm2" class="border">
should be<form id="testForm3" class="border">
So DELETE request can work. - views/issue.html at line 41
var url = "/api/issues/"+currentProject;
should bevar url = "/api/issues/"+currentProject + window.location.search;
So query string of url can work.