Improve test coverage

[teekaay]

Scope

I'm submitting a ...

• bug report
• feature request

Expected Behavior

The code should be tested in more depth. Also, no frontend tests are available.

Actual Behavior

Parts of the code (e.g. endpoints, frontend etc) are not tested at all. Too much is mocked
away, which typically means tightly coupled code. Some parts (like the ones that first have to wait for
Promises to resolve on the toplevel (see this) cannot be tested easily/not at all.

Steps to Reproduce the Problem

1. npm run test
2. Use your favourite test coverage tool (e.g. istanbul)

Specifications

• Version: All
• Platform: All
• Subsystem: All

Additional Information

• We could use a coverage tool (istanbul?)
• Refactor after writing a test