[UI] [Container] launching new container has unclear error message: "Invalid: Undefined" about rancher

[vincent99]

What's happening is if you focus the user field then the value in the model changes from null to empty string, which causes the server to send back:

{
    "actions": {},
    "code": "MinLengthExceeded",
    "detail": null,
    "fieldName": "user",
    "id": "b8b40dc6-d1ef-4453-98f3-2a2564ebec59",
    "links": {},
    "message": null,
    "status": 422,
    "type": "error"
}

So the UI needs to make sure fields that are empty are null in the JSON, or the API needs to accept empty strings as not-defined. Also the error display is messed up, rancherio/ui#10

[deniseschannon]

The "Invalid: Undefined" message has been fixed, but the remaining question is whether or not a user must be defined in order to run a command. I've logged a new bug for the remaining question. #270