GitLab

.gitla-ci.yml ...

files to provide people coming from outside an easier understanding for
the implementation

error handling
a little bit code refactoring

foundation for the next step where requests throwing a failure situation are handled by dedicated error response handler
(a lot of files weren't included in the former commit)

are handled by dedicated error response handler

metadata record section of an OAI result needs a namespace - otherwise standard OAI clients are not able to fetch the result

enhanced error handling for wrong verbs based on algebraic data types