It&#x27;s good to see more diagrams&#x2F;flowcharts on the matter, but beyond that - for those that understand the power of abstraction between layers, but you think there should be a simple straightforward to spit out the correct http status code while you worry about the semantics alone: <a href="https:&#x2F;&#x2F;github.com&#x2F;for-GET&#x2F;http-decision-diagram" rel="nofollow">https:&#x2F;&#x2F;github.com&#x2F;for-GET&#x2F;http-decision-diagram</a><p>* an old PoC in NodeJS exists that reads the states&#x2F;transitions from a JSON file and calls the correct callbacks in the correct order. Implement the callbacks (semantics) and you&#x27;re done.<p>Disclaimer: I&#x27;m the author.