Seems related to recent Werkzeug release and that recent Werkzeug releases is only compatible with new Flask releases. Can probably be fixed be specifying minimal version of Werkzeug (the one from flask 0.11) to ensure that old Flask is installed with old Werkzeug, and new Flask with new Werkzeug.
https://travis-ci.org/inveniosoftware/invenio-oaiserver/jobs/530784093
Seems related to recent Werkzeug release and that recent Werkzeug releases is only compatible with new Flask releases. Can probably be fixed be specifying minimal version of Werkzeug (the one from flask 0.11) to ensure that old Flask is installed with old Werkzeug, and new Flask with new Werkzeug.