Unable to update route path through HTTP PUT

[denismakogon]

Similar to #380 API is not restrictive, so i can create a route

curl -X POST -d '{"route":{"type": "sync", "path": "/hello-sync-private", "image": "iron/hello"}}' localhost:8080/v1/apps/testapp/routes

And then will try to update it

curl -X PUT -d '{"route":{"type": "async", "path": "/hello-sync", "image": "iron/hello"}}' localhost:8080/v1/apps/testapp/routes/hello-sync-private

So, type can be modified because response shows that type is changed:

{"message":"Route successfully updated","route":{"app_name":"testapp","path":"/hello-sync-private","image":"iron/hello","type":"async","config":null}}

It appears that there's immutable attribute - path, but API accepts request without saying that such modification forbidden due to immutability nature of an attribute.

In order to fix issue it would be nice to have:

• doc that reflects immutability/mutability of an attributes
• make API more restrictive by returning HTTP 403 in cases when user attempts to modify immutable attribute.