Use hostname when dynoid not provided

[mestachs]

Self proof reading checklist

• Did I run Pronto and fixed all warnings (pronto run -c origin/dev)
• Make sure all naming and code will remain understandable in 6 month by someone new to the project or by you.
• Did I test the right thing?
• Did I test corner cases, non happy path (defensive testing)?
• Check that I used the ad-hoc patterns and created files accordingly (Presenters, Services, Search object, Form object,...)
• Check code efficiency with record intensive project
• Update documentation,readme accordingly

Thanks!