HTTP POST to /apps/{app}/routes is not returning HTTP 409 in case of existing similar route

[denismakogon]

HTTP POST to /apps/{app}/routes is not returning HTTP 409 in case of existing similar route. Similar to #253 but for routes.

Steps to reproduce:

1. Create app

2. Create route

curl -H "Content-Type: application/json" -X POST -d '{
    "route": {
        "type": "sync",
        "path":"/hello-sync",
        "image":"iron/hello"
    }
}' http://localhost:10501/v1/apps/myapp/routes

Response:

{"message":"Route successfully created","route":{"appname":"myapp","path":"/hello-sync","image":"iron/hello","memory":128,"type":"sync","config":null}}

3. Repeat [2]

4. List app routes

{"message":"Sucessfully listed routes","routes":[{"appname":"myapp","path":"/hello-sync","image":"iron/hello","memory":128,"type":"sync","config":null}]}

As it can be observed, for 2 HTTP POST request with exact the same data only one route was created.

[ucirello]

I really dispute that 409 is the correct response. First, 4xx are client errors - this is clearly a server-side issue; secondly, assuming that 4xx is the correct error class (which I give in for discussion purposes), I also do not believe 409 is the correct answer. 409 Conflict is to reveal a concurrency problem in competing updates. In this case, we are trying to block a request that shouldn't have taken place anyway - meaning that 400 Bad Request would be a more appropriate response in my opinion.