This is a plugin that makes some API endpoints available to non-admin users, which would be only accessible to admin users.
$ cd /path/to/redmine/plugins
$ git clone git://github.com/FumiX/redmine_shared_api.git redmine_shared_api
Then restart redmine.
Compatible with: Redmine 5.1.x, 5.0.x, 4.0.x, 3.2.x, 3.1.x, 3.0.x, 2.6.x, 2.5.x
This plugin is released under the GPL v2 license. See LICENSE for more information.