List Api returns 404 NotFound instead of 200 OK with empty list - AppRole Roles (and possibly others)

[rajanadar]

Vault Version: 0.6.1
Sample API: /auth/approle/role?list=true

Steps:

1. Startup Vault
2. Enable an AppRole auth backend
3. Query the existing approles in the backend using the API: /auth/approle/role?list=true

Observed Result:

404 Not Found (WebException) is observed.

Expected Result:

would it be better if the API returned a 200 OK with zero results?
404 would make sense for a single REST resource. when you are looking for it with an id.

In case of a collection of resources, an empty list of roles sounds more useful for the callers. (and probably aligns to how REST Apis work)
Otherwise the callers now need to catch 404 exceptions.. and expose out an empty list.

p.s. i verified it for the AppRoles api, but this may be applicable to other List APIs as well.

[rajanadar]

also, should the api be /auth/approle/roles instead of /auth/approle/role? (plural roles)
The documentation page mentions singular.

[jefferai]

See #1365